Critique of two research articles

Markingfeedbackform Quantitativeresearchpaper Critiqueguide Qualitativereseachpaper Lecture3Non-experimentalobservationaldesigns Lecture6IntroductiontoQualitativeResearch Lecture9Interpretingandcritiquingqualitativeresearch Lecture8Criticalappraisalquant Lecture5Inferentialstatisticalanalysis Lecture4samplingvalidityandreliability Lecture7Qualitativemethodsofdatacollectionandanalysis Lecture2Experimentaldesigns

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PH2600Research Methods BSc(Hons) Physiotherapy
Critique Marking/ Feedback Form

Student No: Markers Initials: Date:

Quantitative paper section
Student provides a context
for the article that is being
critiqued

Identifies 3 clear features
of the design or reporting
of the study as strengths
or limitation (note: at least
one must relate to the
data analysis or results).

Makes a case for each
feature demonstrating
knowledge of the relevant
principles of research
methods and how that
feature might impact on
the study’s results or
conclusions.

/35

Summarises the main
points of the critique

/5
Quantitative paper section
Student provides a context
for the article that is being
critiqued
/5
Identifies 3 clear features
of the design or reporting
of the study as strengths
or limitation (note: at least
one must relate to the
data analysis or results).

Makes a case for each
feature demonstrating
knowledge of the relevant
principles of research
methods and how that
feature might impact on
the study’s results or
conclusions.
/35
Summarises the main
points of the critique
/5

Presentation/ Referencing
Overall grammar, spelling,
quality of writing

Referencing appropriate

/10

TOTAL MARK /100
General Comments

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Physiotherapy

97 (2011) 250–255

Effect of motion control running shoes compared with neutral
shoes on tibial rotation during running

Alice Rose a,∗, Ivan Birch b, Raija Kuisma

a
a

Division of Physiotherapy, School of Health Professions, University of Brighton, UK

aculty of Health and Human Sciences at Thames Valley University, UK

bstract

bjective To determine whether a motion control running shoe reduces tibial rotation i

n the transverse plane during treadmill running.

esign An experimental study measuring tibial rotation in volunteer participants using a repeated measures design.
etting Human Movement Laboratory, School of Health Professions, University of Brighton.
articipants Twenty-four healthy participants were tested. The group comprised males and females with size 6, 7, 9 and 11 feet. The age

ange for participants was 19 to 31 years.
ain outcome measures The total range of proximal tibial rotation was measured using the Codamotion 3-D Movement Analysis System.
esults A one-tailed paired t-test indicated a statistically significant decrease in the total range of proximal tibial rotation when a motion

ontrol shoe was worn (mean difference 1.38◦, 95% confidence interval 0.03 to 2.73, P = 0.04).

onclusions There is a difference in tibial rotation in the transverse plane between a motion control running shoe and a neutral running shoe.
he results from this study have implications for the use of supportive running shoes as a form of injury prevention.
2010 Chartered Society of Physiotherapy. Publis

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eywords: Tibial rotation; Running; Motion control shoe

ntroduction

In today’s society, one of the greatest challenges faced by
he Department of Health is the growing epidemic of obesity.
he cost of overweight and obese individuals to the National
ealth Service is estimated to be £4.2 billion [1]. This has led

o considerable media attention on the wider health risks of
ur sedentary lifestyles, and has resulted in an increase in the
umber of people participating in recreational running [2].
n order to understand the effect of running shoes on gait, a
asic knowledge of lower limb mechanics is essential.

Within the first 20% of the stance phase, the subtalar joint
ronates to allow solid contact of the foot with the ground
3]. As forward progression continues through the middle of
he stance phase, maximum pronation and ankle dorsiflexion

ccur. Pronation is a normal part of the running cycle because
t allows for shock absorption and accommodation on uneven
errain [3]. However, in some individuals, excessive pronation

∗ Corresponding author.
E-mail address: alice2rose@googlemail.com (A. Rose).

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031-9406/$ – see front matter © 2010 Chartered Society of Physiotherapy. Publis
oi:10.1016/j.physio.2010.08.013

ay occur for various biomechanical reasons [4]. Excessive
ronators present with a broad range of pathologies, such as
tress fractures, achilles tendonitis and iliotibial band (ITB)
endonitis [4]. Yates and White studied naval recruits and
ound that those with a pronated foot type were almost twice
s likely to develop medial tibial stress syndrome compared
ith those with a normal or supinated foot posture [5]. A

isk estimate revealed that recruits with a more pronated foot
ype had a higher relative risk (1.70) than injury-free recruits.
n an attempt to minimise the risk of injury, athletes have
tarted to seek specific equipment, particularly running shoes
5].

Neutral cushion shoes are generally best for runners with
n excessive supinatory gait to provide additional shock
bsorption, whereas motion control shoes are better for
he moderate to severe overpronator. Motion control shoes
nclude a reinforced heel counter and a denser midsole to

elp control any excessive pronation [5]. Clarke et al. [6]
ound that shoes with a positive heel flare and a hard midsole
llowed significantly less maximum pronation and total rear-
oot movement compared with shoes with a softer midsole.
hed by Elsevier Ltd. All rights reserved.

dx.doi.org/10.1016/j.physio.2010.08.013

mailto:alice2rose@googlemail.com

dx.doi.org/10.1016/j.physio.2010.08.013

therapy

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A. Rose et al. / Physio

Research has shown that motion control shoes also have
n effect on tibial internal rotation [7]. This is a normal part
f the gait cycle and occurs in conjunction with pronation
nd hindfoot eversion due to the mitered hinge effect of the
ubtalar joint [3]. Running can lead to an increase in inter-
al tibial rotation for people with excessively pronated feet.
iller et al. [8] found that runners with a history of ITB syn-

rome demonstrated increased tibial internal rotation. They
redicted that an increase in internal rotation of the tibia could
ncrease the strain in the ITB, and therefore be a contribut-
ng factor to ITB syndrome. However, the critical degree of
nternal tibial rotation leading to injuries has not been con-
rmed, and research is required in this area. It is reasonable

o assume that by reducing rearfoot pronation with motion
ontrol shoes, tibial rotation would consequently decrease
hen running. This may support the use of supportive running

hoes as a form of injury prevention. To date, there is mini-
al evidence on the effects of running shoes on tibial rotation

8–10]. Stacoff et al. [10] used intracortical bone pins with
njury-free participants to measure the effects of shoe sole
onstruction on skeletal motion during running. They found
o statistically significant change in tibiocalcaneal rotations.
t was concluded that the tibiocalcaneal kinematics of running
ay be unique to the individual, and shoe sole modifications
ay not be able to make substantial changes.
Running gait can be analysed using a number of m

ethods

ncluding real-time observational gait analysis, high-
esolution cameras and video-recording devices, force plates
nd computer systems. Computerised three-dimensional (3-
) motion analysis measurements are currently a widespread

nd useful tool for both clinical practice and biomechanical
esearch. The Coda motion 3-D Movement Analysis System
s able to measure locations of active markers in 3-D with
igh resolution and accuracy. Maynard et al. [11] studied the
ntra- and inter-rater reliability of gait measurements using
Cartesian optoelectronic dynamic anthropometer (CODA,
harnwood Dynamics Limited based in Leicestershire).
hey suggested that natural variation of the participant’s gait
ycle may be overcome by capturing at least three gait trials.
hey concluded that they had not shown complete repro-
ucibility of gait measurements using CODA, but this does
ot suggest that CODA is unreliable. Many studies have used
ODA in the past and none have recorded any anomalies or
rrors attributal to CODA itself [12,13].

Published literature suggests that running footwear can
nfluence lower extremity kinematics and kinetics. Currently,
esearch into the effects of running footwear on tibial rotation
s limited. Therefore, the aim of this study was to determine
hether motion control running shoes reduce tibial rotation

n the transverse plane during treadmill running.
ethods

An experimental study was conducted with two condi-
ions: neutral shoes and motion control shoes. The effect on

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97 (2011) 250–255 251

ange of tibial rotation in the transverse plane during tread-
ill running in the two styles of running shoes was measured

n degrees.

articipants

Ethical approval was gained from the School Ethics Com-
ittee at the University of Brighton. Thirty-two consecutive

olunteers from the University of Brighton health profes-
ional courses who responded to a recruitment e-mail were
ncluded. This e-mail included an information sheet for par-
icipants to read before volunteering. On arrival at the Human

ovement Laboratory, all details of the study were explained
o participants and they were asked to sign a consent form.

In order to be included, participants were required to have
ize 6, 7, 9 or 11 feet and be able to run comfortably for 5 to
0 minutes. Participants were excluded from the study if they
ad a history of cardiovascular problems, a lower limb con-
ition that was exacerbated by running, a vestibular disorder
r an allergy to hypoallergenic adhesive tape.

nstrumentation

A Biodex RTM 500 treadmill (Biodex Medical Systems,
nc., New York, USA) was used for all participants and for
oth conditions. The treadmill was placed in the middle of the
aboratory with one CODA MPX30 (Charnwood Dynamics
td., Leicester, UK) scanner unit in front and one scanner
nit behind. These units picked up signals emitted by the
nfra-red ‘active’ markers which provided an immediate and
recise 3-D measurement. All information from the scanners
as stored on the CODA computer system.

rocedure

A pilot study was carried out on one individual to test the
roposed methodology. No problems were experienced, so
o changes were made to the methodology. The data from
he pilot study were included in the main results.

The laboratory was set up before participants arrived on
he first day. The origin or zero point of the system’s mutually
rthogonal measurement framework was established by plac-
ng a single marker in the centre of the treadmill, mid-way
etween the two sensor units. The alignment of the system’s
, Y and Z axes was set using two additional pairs of mark-
rs. The orientation of the three axes used throughout the data
ollection was as follows:

positive Y axis – direction of walking;
positive X axis – to the participant’s right;
positive Z axis – up.

All data were collected using the right leg, and the axis
rientation was set in accordance with the recommendations
f the Standardization and Terminology Committee of the
nternational Society of Biomechanics [14].

252 A. Rose et al. / Physiotherapy 97 (2011) 250–255

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Data analysis

The first useable set of data of the three sets collected per
participant was used for data analysis. The average range of

ig. 1. Neutral shoe: Mizuno Wave Rider.

Participants were asked to attend a single session last-
ng approximately 30 minutes. Participants were asked to
ome wearing shorts and to put on the neutral pair of run-
ing shoes (Fig. 1) before marker attachment took place.
ctive markers were attached using double-sided hypoaller-
enic adhesive tape to the following landmarks on the right
eg: medial condyle of tibia, head of fibula, tibial tuberos-
ty, two-thirds of tibial shaft, medial malleolus and lateral

alleolus (Fig. 2). Marker placement complied with the Joint
o-ordinate System recommendation [9]. Technical markers

medial condyle of tibia and two-thirds of tibial shaft) were
sed to define the co-ordination of the virtual markers dur-
ng running trials. Batteries were connected to the markers
nd attached to the leg using hypoallergenic adhesive tape.
he safety clip of the treadmill was attached to the partici-
ants and they were given a 5-minute practice run to allow
hem to adapt to the treadmill motion and the shoes. Lav-
anska et al. found that it takes 5 to 6 minutes to become
amiliar with treadmill running; therefore, participants were
cclimatised for this period prior to commencement of
easurements. The treadmill speed was then gradually

ncreased to 8 km/hour [15]. The average running speed
f unimpaired young adults is between 7 and 9 km/hour
15].

Participants were shown the emergency stop button and
ssured that they could stop running at any time. Confirmation
as gained that the participant was happy running at this

peed. On confirmation, lights were switched off to do a ‘test’
ollection of data to ensure that all markers were in view of
he scanners. One researcher carried out all the tests with an
ssistant to help. If all the markers were in view, three sets
f data were collected and saved to the computer. If a marker
ent out of view at any point, the treadmill was stopped and

he markers were adjusted accordingly or retaped. Once the
hree sets of data were saved, participants dismounted the
readmill and changed into the motion control shoes (Fig. 3).

arkers were checked for secure attachment. The procedure

as then repeated for the motion control shoes. All data were

aved to a password-secured computer. F

ig. 2. Front view of active markers.

ig. 3. Motion control shoe: Mizuno Wave Inspire.

A. Rose et al. / Physiotherapy

Table 1
Total range of proximal tibial rotation in the XY plane of the Cartesian
optoelectronic dynamic anthropometer for the two running shoes.

Participant Total range of tibial
rotation (degrees)

Neutral
shoe

Support
shoe

Difference
(◦)

1 10 16 −6
2 4 9 −5
3 5 9 −4
4 10 14 −4
5 12 14 −2
6 7 7 0
7 6 6 0
8 22 21 1
9 17 16 1
10 8 7 1
11 5 4 1
12 9 8 1
13 15 14 1
14 7 5 2
15 23 21 2
16 9 6 3
17 18 15 3
18 18 15 3
19 10 7 3
20 12 8 4
21 11 6 5
22 20 14 6
23 10 4 6
24 28 17 11
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reduction in peak rearfoot eversion for runners in the motion

ean Standard deviation 12.3 (6.4) 10.9(5.3) 1.4 (3.8)

otion of the leg in the transverse plane during the contact
hase of running was calculated using CODA. The data were
opied into Microsoft Excel, and graphs were plotted to show
he total range of proximal tibial rotation in the XY plane of
ODA for the two running shoes. A one-tailed paired t-test
as used to test for differences in tibial rotation recorded for

he two experimental conditions (neutral and motion control
hoes), and the P-level was set at 0.05.

esults

All 32 participants took part in the study, but only 24
articipants provided adequate data for analysis. Naturally,
very individual’s running gait is different and sometimes this
eant that the signals from the active markers were not picked

p by the scanner units. This occurred for eight of the partic-
pants; therefore, the data were excluded from the analysis.
able 1 shows the data collected from the 24 participants.

The paired t-test revealed a statistically significant dif-
erence in tibial rotation between the two conditions (mean
ifference 1.38◦, 95% confidence interval 0.03 to 2.73,
= 0.04). This showed that there is a statistically significant

ifference in tibial rotation in the transverse plane during
readmill running when using motion control running shoes
ompared with neutral running shoes.

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97 (2011) 250–255 253

The overall trend showed that the total range of proximal
ibial rotation for participants running in motion control shoes
mean 10.9◦, standard deviation 5.3◦) was smaller compared
ith running in neutral shoes (mean 12.9◦, standard devia-

ion 6.4◦). The largest individual difference was 11◦, but the
ean difference between the two conditions was small (mean

.38◦). The tibial rotation in five participants was smaller in
he neutral running shoes (Table 1).

The largest difference was 11◦; two participants had a total
ange of tibial rotation of 10◦ in the neutral shoes and 4◦ in
he motion control shoes.

iscussion

The aim of this study was to determine whether motion
ontrol running shoes reduce tibial rotation in the transverse
lane during treadmill running, with implications for injury
revention. The findings suggest that there is a statistically
ignificant difference in tibial rotation in the transverse plane
uring treadmill running between motion control running
hoes and neutral running shoes. The total range of proxi-
al tibial rotation was generally reduced when participants

an in motion control shoes. Although the mean difference
as rather small, some participants demonstrated a differ-

nce which was half of the total range, and hence could be
linically significant in their cases.

Clarke et al. [6] analysed the effects of different shoe
esign parameters on rearfoot control in running. They found
hat participants displayed an average of approximately 2.7◦
maller maximum pronation when running in shoes with a
ard midsole compared with a soft midsole. If rearfoot motion
nd tibial rotation are taken as a coupled mechanism [3], it can
e assumed that this is the mechanism by which tibial rotation
as reduced in this study. Controlling rearfoot motion with

unning in motion control shoes will subsequently reduce the
articipant’s tibial rotation. The results from the current study
upport this assumption because the total range of proximal
ibial rotation was reduced when running in motion control
hoes compared with running in neutral shoes for the major-
ty of participants (79%). For example, one participant had a
otal range of tibial rotation of 28◦ in the neutral shoes and
7◦ in the motion control shoes (reduction 11◦).

The results from the current study relate to similar research
y Butler et al. [7], which showed that in low arched run-
ers, peak tibial internal rotation decreased in motion control
hoes and was increased in cushion shoes. They found no
nteraction between high arched runners and lower extremity
inematics. Since arch height was not measured in the current
tudy, it is unclear if this factor contributed to the degree of
ibial rotation. To confirm this association, further research
eeds to be undertaken in the area. Butler et al. [7] found no

ontrol shoes. This is unusual because if there was a cou-
led relationship between rearfoot eversion and tibial internal
otation, it would be expected that both of these movements

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54 A. Rose et al. / Physio

ould decrease when running in motion control shoes. These
nusual results may be due to the motion control shoes having
ncreased support in the midfoot; therefore, the positioning
f this support would not have influenced rearfoot motion.

This study does not provide direct support for the hypoth-
sis that motion control running shoes are a form of injury
revention; however, it does have some supporting implica-
ions. Miller et al. [8] found that runners with a history of ITB
yndrome demonstrated more tibial internal rotation, thus
uggesting that an increase in tibial internal rotation could
e a contributing factor to ITB syndrome. The links between
ibial rotation and running injuries are further supported by
tergiou and Bates [16]. They investigated knee and ankle
inematics in five runners, and showed a strong relationship
etween pronation and knee joint function via tibial rotation;
his was identified as a possible mechanism for injury. They
ent on to explain that overpronation could lead to maximum
ronation (and subsequent internal tibial rotation) occurring
ater in the stance phase. This could then lead to soft tissue
tress around the knee or patellofemoral malalignment [16].
ince anyone with a lower limb condition that is exacerbated
y running was excluded from this study, the hypothesis that
otion control shoes could be a form of injury prevention for

unners was not tested. However, the links between increased
nternal tibial rotation and running injuries found to date seem
romising, and there is scope for further research.

The Codamotion 3-D Movement Analysis System is easy
o use, and previous studies that have used CODA have
ot found any anomalies or errors attributal to CODA itself
12,13]. However, there are certain limitations that may have
ffected the outcome of the results. The issue of skin move-
ent artefacts when using skin markers in gait analysis has

een raised [3], although tibial rotation is considered to be
ore accurate than other measurements of knee and thigh
ovement [12]. When comparing bone pins with skin mark-

rs, Reinschmidt et al. [12] found an average error of 1.1◦,
mplying that tibial rotation can be determined with reason-
ble accuracy using skin markers. In this study, the active
arkers were placed over bony structures where underlying

oft tissue was minimal, with the hope that skin movement
rtefacts would be minimised. This is especially the case
round the ankle where the skin is tightly bound and there is
decreased chance of soft tissue and skin movement.

Maynard et al. [11] studied the intra- and inter-rater relia-
ility of gait measurements using CODA, and suggested that
atural variation of the participant’s gait cycle may be over-
ome by capturing at least three gait trials. In this study, three
ait trials were captured for each participant and the first use-
ble set of data was used for data analysis. This improved
he reliability of the measurement technique and minimised
otential error.

Although treadmill running allows for easy, continuous

bservation and monitoring, it may cause variation in move-
ent pattern compared with overground running. Therefore,

or a true representation of running biomechanics, tibial rota-
ion would need to be measured over ground.

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97 (2011) 250–255

Five participants did not follow the trend of results
nd showed an increase in tibial rotation when wearing
otion control running shoes compared with neutral shoes.
number of factors could have contributed to this unusual

ifference. During data collection, it became apparent that
here was inconsistency with the level of treadmill experi-
nce between the participants. This could have resulted in
he less experienced participants becoming fatigued by the
ime they reached the second test condition. Links between
atigue and rearfoot kinematics have been recorded [7,17].

Participants in this study ran first in the neutral shoes and
hen in the motion control shoes. This may have contributed
o some of the increases in tibial rotation in the motion control
hoes. To minimise possible order effects, the shoes should
ave been presented in a randomised order. This would have
liminated a potential confounding variable and strengthened
he internal validity of the study. Due to limited funding, only
ight pairs of shoes were used for the study, which excluded
articipants outside the available shoe sizes. Therefore, the
esults may not be representative of the general population.
his study would need to be reproduced with a larger sam-
le size (including all shoe sizes) to make the results more
pplicable to the wider population.

The results from the study are open to observer bias
ecause the researcher collected the study data. To elimi-
ate this potential confounding variable, an independent data
ollector should have been used.

A number of ideas for further research arose while eval-
ating the current study. As highlighted above, the results
rom this study have implications for the theory that motion
ontrol running shoes could be a form of injury prevention
or runners. The experiment could be expanded to include
articipants with running-related injuries. Researchers could
hen investigate to see if injured participants displayed more
ibial rotation in the neutral shoes, and furthermore if this
ibial rotation decreased for these participants when wearing
he motion control shoes.

onclusions

The results from this study show that there is a difference in
ibial rotation in the transverse plane during treadmill running
hen comparing motion control running shoes with neutral

unning shoes. This is indicated by the statistically significant
ecrease in the total range of proximal tibial rotation when
otion control shoes were worn. Previous research findings

ave demonstrated links between increased tibial rotation and
unning injuries [8,9]. The results from this study therefore
uggest that supportive running shoes may have an important
ole to play in running injury prevention.

cknowledgements

The authors would like to thank Amy Grimadell, Leigh
agan and Nicole Nielsen for assisting with data collection;

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1997;6:177–85.
[17] Gerlach K, White S, Burton H, Dorn J, Leddy J, Horvath P. Kinetic

A. Rose et al. / Physio

aul Stevens at Mizuno Ltd. for providing the running shoes
or this study; and all the participants from the University of
righton.

thical approval: School of Health Professions Research
thics and Governance Panel at the University of Brighton.

onflict of interest: None declared.

eferences

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[3] Dungan S, Bhat K. Biomechanics and analysis of running gait. Phys
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[4] Yamashita M. Evaluation and selection of shoe wear and orthoses for
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[6] Clarke T, Frederick E, Hamill C. The effects of shoe design parameters

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[7] Butler R, Hamill J, Davis I. Effect of footwear on high and low
arched runners’ mechanics during a prolonged run. Gait Posture
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[9] Eslami M, Begon M, Farahpour N, Allard P. Forefoot-rearfoot coupling
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11] Maynard V, Bakheit A, Oldham J, Freeman J. Intra-rater and inter-rater
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12] Reinschmidt C, Van den Bogert A, Nigg B, Lundberg A, Murphy N.
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13] Monaghan K, Delahunt E, Caulfield B. Ankle function during gait
in patients with chronic ankle instability compared to controls. Clin
Biomech 2006;21:168–74.

14] Wu G, Siegler S, Allard P, Kirtley C, Leardini A, Rosenbaum D, et al.
ISB recommendation on definitions of joint coordinate system of vari-
ous joints for the reporting of human joint motion – part 1: ankle, hip,
and spine. J Biomech 2002;35:543–8.

15] Lavcanska V, Taylor N, Schache A. Familiarization to treadmill running
in young unimpaired adults. Hum Mov Sci 2005;24:544–57.

16] Stergiou N, Bates B. The relationship between subtalar and knee joint
function as a possible mechanism for running injuries. Gait Posture

changes with fatigue and relationship to injury in female runners. Med
Sci Sport Exerc 2005;37:657–63.

ciencedirect.com

http://www.dh.gov.uk/en/Publichealth/Healthimprovement/Obesity/DH_6585

Effect of motion control running shoes compared with neutral shoes on tibial rotation during running

Introduction
Methods
Participants
Instrumentation
Procedure
Data analysis
Results
Discussion
Conclusions
Acknowledgements
References

PH2600Research Methods

Essay: Critique of research articles

Guidance

2019/ 20

The purpose of this assessment is for you to demonstrate your understanding of research

methods by completing a critique of published literature. You will be required to critique

two research articles which have been chosen by the module team. One paper will

involve qualitative methods and one paper quantitative methods. The titles of research

articles will be released on Blackboard Learn in the folder titled Assessment Information.

Your critique essay should be up to 2000 words long and should not exceed this word

limit. The mark awarded for this essay constitutes 100% of the overall module grade.

Guidance for the critique

The quantitative research paper you are being asked to critically appraise is:

Rose, A., Birch, I., Kuisma, R. (2011) ‘Effect of motion control running shoes compared

with neutral shoes on tibial rotation during running.’ Physiotherapy, 97, pp. 250–255

The qualitative paper you are being asked to critically appraise is:

Sharma, H., Bulley, C., van Wijck, F. (2012) ‘Experiences of an exercise referral scheme

from the perspective of people with chronic stroke: a qualitative study.’ Physiotherapy,

98, pp. 336–343

For each paper identify and discuss 3 aspects of the study that you think represent either

a strength or a limitation of the study and explain why you think that is so. These could

include anything from whether the research question is well explained and justified,

whether the overall design is appropriate for the question, how specific aspects of the

design or conduct of the study might impact on validity (internal or external), coherence

or rigour, the approach taken to analysing data or whether the way that the authors of

the paper present and interpret the results is fair and balanced.

For both papers at least one of those 3 aspects must relate to the choice of data analysis

or the actual results section. You should structure your critique in the following manner:

Write it in 2 distinct sections of around 1000 words each. Each section should focus on

one of the papers. The text should read like a fully developed narrative. Bullet point lists

are not acceptable. This is an exercise in academic writing and constructing critical

arguments/ explanations.

For each section follow this format

Introduction. Open with a short section that describes the paper, its topic area and the

research question it seeks to answer. Offer some brief context.

Main body of the critique.

Identify 3 features from each paper that you think represent either strengths or

limitations. For each of these features justify your answers by explaining how these

features have impacted the study or affect our confidence in the conclusions. In this you

will need to show your knowledge of the relevant research methods.

Conclusion. This section should offer a concise and balanced summary of what you have

presented in the main body of the critique. It should summarise the main points that you

have made. You should not be presenting new information here; if something is

important, it should have been mentioned in the main body of the critique.

Wordage. Your essay should be up to 2000 words long with no allowance for extra words.

Your submission may be less than the maximum wordage. If you exceed the upper word

limit, the excess part of your critique will not be read or marked. All content (except for

any tables, charts and references within brackets in the main body of the text) between

the title and reference list is included in the word count.

Referencing.

You need to reference the research article that you are critiquing. Where appropriate you

should also use other referenced resources (i.e. research methods textbooks and journal

articles) to support the points that you are making but remember this is primarily a

critique of the papers themselves, so an extensive and lengthy reference list is not

expected. All references need to be presented in the Harvard style. For detailed guidance

on how to reference see https://libguides.brunel.ac.uk/referencing/overview. The link is

also available on BBL).

Formatting

Please pay attention to the presentation of your work. The work should have a clear title

and your student number should be present. The text should read like a fully developed

narrative. Bullet point lists are not acceptable. This is an exercise in academic writing and

constructing critical arguments/ explanations.

*Do not have your name anywhere on the documents.*

The work should be formatted as follows:

Font: Calibri, Arial or Times New Roman, size 11

Line spacing: 1.5

Margins: Normal (around 2.54cm)

Submission of your assignment.

The submission deadline for the critique is: 12pm midday on Tuesday 21ST April 2020

The submission will be made electronically on WISEFLOW. Further details to follow.

For the electronic submission, please submit your essay as a pdf.

LABEL YOUR FILES AS FOLLOWS:

studentnumber_CRITIQUE (E.G. 98765432_CRITIQUE)

Feedback

https://libguides.brunel.ac.uk/referencing/overview

All students will receive provisional written feedback on this assessment during the week

beginning 11/5/2020.

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Physiothera

py 98 (2012) 336–343

Experiences of an exercise referral scheme from the perspective of people
with chronic stroke: a qualitative study

Helen Sharma a, Cathy Bulley

, Frederike M.J. van Wijck c,∗
a Physiotherapy Department, King’s College Hospital, Denmark Hill, London SE5 9RS, UK

b School of Health Sciences, Queen Margaret University, Queen Margaret University Drive, Edinburgh EH21 6UU, UK
c Institute of Applied Health Research and School of Health, Glasgow Caledonian University, Cowcaddens Road, Glasgow GB4 0BA, UK

bstrac

bjective To explore stroke survivors’ experiences of undertaking exercise in the context of an exercise referral scheme for people with
hronic stroke.
esign A qualitative design, using semi-structured interviews within a constructivist framework to explore the experiences of individ-
al participants. Verbatim transcripts were thematically analysed. Rigour mechanisms included respondent validation, peer checking, and
eflexivity.
etting An exercise referral scheme, based at a leisure centre in South London.
articipants Nine community-dwelling stroke survivors took part; 5 male and 4 female, mean age 51 years (range 37–61 years); time post
troke 1–4 years, with mixed ethnic backgrounds.
indings Participants described greater physical and psychological well-being following participation in the exercise referral scheme.
ategories that emerged were: improved exercise engagement and confidence, more internalised perceptions of control and enhanced lifestyle,
ork and social roles. Categories linked to form a master theme, labelled: ‘Exercise Referral Scheme as a catalyst for regaining independence.’

onclusions This study supports the value of exercise referral schemes in enabling people with stroke to engage in exercise. For participants

n this study, the scheme seemed influential in the process of regaining independence.
2011 Chartered Society of Physiotherapy. Publis

eywords: Stroke; Exercise; Physical activity; Exercise referral scheme; Community

[

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ntroduction

Globally, fifteen million people suffer a stroke each year
nd with five million being left permanently disabled, stroke
laces a considerable burden on family, community and econ-
my [1]. In England, stroke is the largest single cause of adult
isability; over 900,000 people live with the consequences
f stroke, with associated costs estimated at over seven bil-
ion pounds per year [2]. The impact of stroke on individuals

ay include reduced independence, low mood, sensorimotor
mpairment and decreased fitness.

∗ Corresponding author. Tel.: +44 0141 3318967.
E-mail addresses: hrsharma@btinternet.com (H. Sharma),

bulley@qmu.ac.uk (C. Bulley), Frederike.vanWijck@gcu.ac.uk
F.M.J. van Wijck).

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031-9406/$ – see front matter © 2011 Chartered Society of Physiotherapy. Publis
oi:10.1016/j.physio.2011.05.004

Reduced physical fitness is common following stroke
3], presenting a risk for recurrent stroke, cardiac disease
nd fall-related fractures [4,5], and a barrier to community
e-integration [6]. With more people surviving strokes [7]
nd government policies shifting health care from hospi-
al towards community [8], improving physical fitness in
ommunity-dwelling stroke survivors is a priority.

A growing body of evidence demonstrates that exercise,
efined as structured and repetitive physical activity (PA) that
s usually planned to enhance fitness [9], can improve a range
f fitness parameters after stroke [10]. However, evidence
lso suggests that PA must be maintained to sustain bene-
ts [11]. UK national clinical guidelines recommend regular

xercise participation and aerobic training where possible, as
art of a long-term strategy after stroke [12–14].

Studies of PA maintenance after stroke are scarce. One
eport demonstrated immediate reductions in PA follow-

dx.doi.org/10.1016/j.physio.2011.05.004

mailto:hrsharma@btinternet.com

mailto:cbulley@qmu.ac.uk

mailto:Frederike.vanWijck@gcu.ac.uk

dx.doi.org/10.1016/j.physio.2011.05.004

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H. Sharma et al. / Phys

ng completion of an exercise programme, and return to
ow levels three months later [15]. General population sur-
eys have found that maintaining sufficient levels of PA
s difficult [16]. To encourage ongoing exercise participa-
ion among different populations, exercise referral schemes
ERS) were developed in the UK [17]. However, four ran-
omised controlled trials (n = 1200 in total) found a return to
re-intervention exercise levels at 12-to-52 weeks after com-
leting an ERS [18–23]. Reasons for this decline in exercise
ehaviour are unclear, mainly due to a lack of qualitative data.
xercise behaviour is complex; one review identified over
0 correlates of exercise participation in adults [24]. With
he ERS model now well established, knowledge of partic-
pants’ experiences with this type of service is essential to
ptimise uptake and ongoing PA participation. Although the
alue of patient experiences in service design and delivery is
ell recognised by the UK National Health Service (NHS)

25] and government policies [26], little is known about
troke survivors’ experiences of exercise in the context of
n ERS.

The first qualitative study to formally explore the expe-
iences of stroke survivors of an exercise intervention [27]
as associated with a clinical trial [11] and found that partic-

pants had enjoyed the classes, felt empowered to take more
ontrol over their recovery, and more motivated to get out
f the house and undertake other activities. Most exercise
articipants continued with an active lifestyle afterwards,
nd felt their quality of life had increased. Another clinical
rial [28] included an exploration of stroke survivors’ percep-
ions of a community-based scheme combining exercise with
ducation [29]. Exercise and goal setting were valued as pos-
tive actions that enabled improvements in physical function
nd confidence. However, these interventions were delivered
ithin the context of clinical trials, and the findings may not
eneralise to routine clinical practice.

To our knowledge, only one study has explored experi-
nces of a community-based ERS for stroke survivors [30],
nd included people with stroke, fitness instructors who
an the scheme and referring physiotherapists. Four main
hemes emerged: the role of the ERS in continuing rehabili-
ation following physiotherapy discharge; concern regarding
nstructors’ level of knowledge about stroke; low levels
f supervision and interaction with instructors; and sug-
ested improvements to the scheme, including closer contact
etween referring physiotherapists and exercise instructors.
owever, perceived impacts of the scheme on participant’s

ives were not explored, and it was not possible to isolate the
xperiences of stroke survivors.

In summary, published literature on exercise after stroke
ocuses primarily on physical impairments and activity limi-
ations, with little information on perceptions and experiences
elating to exercise and any psychosocial impacts of exer-

ise referral schemes. Therefore, the aim of this study
as to explore the experiences of people in the chronic
hase after stroke, who participated in a community-based,
hysiotherapy-led ERS.

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py 98 (2012) 336–343 337

ethod

tudy design

Individual experiences were explored in depth using a
onstructivist qualitative approach that focuses on socially
onstructed multiple realities [31]; an interpretivist per-
pective that appreciates individuals’ values and meanings;
nd phenomenological methodology, whereby the researcher
brackets’ personal understandings when deriving meaning
rom the data [32].

One-off, one-to-one semi-structured interviews enabled
n individual focus and coverage of important topics with-
ut limiting responses [33]. Approval was granted by the
esearch and Development centre attached to the Primary
are Trust that was responsible for the ERS, and by both
thics committees of the lead researcher’s Higher Education
nstitution and NHS employer.

ample population and recruitment

The study context was an exercise programme provided
hrough an ERS based at a South London leisure centre,
upervised by a chartered physiotherapist and specific to peo-
le with neurological conditions. The ERS is defined in this
tudy as “the referral to, and uptake of, a physiotherapist-
ed exercise programme”. Individually tailored gym-based
xercise took place in a group format, twice weekly, for up
o three months. Participants were generally referred by a
hysiotherapist at least six months after their stroke.

The study population included people with a primary diag-
osis of stroke who had attended the ERS within the previous
wo years, over which recall of experiences was considered
ealistic. To capture varied experiences, attendance levels and
RS completion were not prerequisites for selection. Poten-

ial participants were identified by the lead researcher (HS),
sing NHS patient records and were sent invitation letters,
nformation sheets and consent forms. Those returning con-
ent forms were telephoned to screen for factors that would
ender an in-depth interview unfeasible, including inability
o engage in conversation, a voice potentially incomprehensi-
le on audiotape, or inability to recall their ERS experiences.
articipants were offered interviews at their venue of choice.
t was thought unethical to undertake further measures to
ncrease recruitment rate.

rocedure

The lead researcher (HS) was a female chartered phys-
otherapist with 2 years’ general experience, and 3 years
pecialising in neurology. She was employed at the ERS
s the primary clinician, but only after participants in this

tudy had been discharged, minimising impacts from prior
nowledge or relationships. Participants were aware of her
ackground but the importance of their views and experiences
as emphasised.

338 H. Sharma et al. / Physiotherapy 98 (2012) 336–343

Table 1
Summary of topic guide.

Topic Example question

Demographics Confirm age, time of stroke, when attended ERS
Meaning of exercise to individual What do you think of when I say ‘exercise’?
Past experience of exercise Before your stroke, how active were you? What sorts of things did you do?
Impact of stroke on exercise behaviour How did your stroke affect the exercise that you could do?
Experience before attending ERS Before you went to the ERS, what did you think it would be like? Why do you think you thought that?
Experience of ERS How did you feel about exercising in this way?

Is there anything you didn’t enjoy? Why was that?
Transition from ERS to independent exercising Did you have any plans to carry on exercising? How did that go?
Current status Is there anything from your experience of ERS that affects your life now? Why is that?
The future Do you have any future plans when it comes to exercise?

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RS: exercise referral scheme.

An interview topic guide was developed to address the
tudy aims, informed by relevant literature. The questions,
ummarised in Table 1, explored experiences of accepting a
eferral to an exercise programme, participating, and percep-
ions of any impacts. Participants’ experiences of exercise
efore stroke, and their understanding of the word ‘exer-
ise’ were explored. Maintenance of exercise participation
fter programme completion was also addressed, based on
oncerns raised by Morgan [34]. Questions were structured
hronologically to aid recall, and phrasing provided scope
or additional areas to emerge [35]. Only the interviewer and
nterviewee were present at each interview.

A video-recorded, role-played pilot interview enabled
efinement of the interview technique and further devel-
pment of the topic guide. Review of this pilot interview
dentified possible influences on the credibility of the partici-
ants’ responses. This reflexive process continued throughout
ata collection through a research diary to minimise effects
iases and presuppositions [32].

ata analysis

Interviews were audiotaped and transcribed verbatim. Par-
icipant verification of initial interpretation took place using
nterview summaries. In-depth analysis used an iterative cod-
ng process, moving towards greater levels of abstraction
36]. Text was first read and re-read by the lead researcher,
nd annotated with labels that described concepts (first level
hemes). Similar labels were grouped where they described
elated ideas, and given another label (second level theme).
urther abstraction led to the creation of categories (third

evel themes), and finally a master theme (Table 2). This
as iterative, as text from all interviews was analysed. Anal-
sis was considered complete when no new themes were
efined and all relevant text was incorporated in a theme.

word processing package was used rather than a qualita-
ive data analysis programme; while the latter is useful for

ata management, it does not perform the thinking, and can
reate distance from the text [37]. A sample of themes and
ontributing text units was reviewed by an experienced qual-
tative researcher (CB); discussion led to consensus between

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esearchers, which enhanced dependability of the analysis
38].

esults

articipant characteristics

Of forty-one invited participants, 12 consented, three of
hom could not be included: one was not contactable, one
as not sufficiently fluent in English, and one could not

ecall ERS participation. Interviewed participants included
our female and five male community-dwelling adults (mean
ge 51; range 37–61 years), who had had a stroke one to
our years previously. Four were of White English, one White
rish, and four Black African ethnic origins. Interviews lasted
5–80 minutes. Six occurred in participant’s homes, one at
heir workplace, and two at a hospital office.

ategories

Four categories emerged: exercise engagement (i.e. rel-
vant behavioural changes); improvement (i.e. individuals’
nterpretations of physical and psychological improvements);
ontrol (changing views regarding who was responsible for
ncreased feelings of independence); and finally, confidence
i.e. a growing sense of self-confidence in the individual’s
bility to exercise). The account focuses on varied experi-
nces, rather than consensus views. Pseudonyms have been
sed throughout.

xercise engagement
Between the stroke and ERS, participants recalled slow-

ng down and making adjustments to lifestyle, work and
ocial roles. This pace-change appeared to be challenged by
RS attendance, which facilitated increases in activity levels
ithin sessions, and outside the ERS:

Before I started going [to the exercise referral scheme], I
asn’t thinking about exercise, and I wasn’t thinking about
nything, other than sit at home, eat and watch television.
hen I started, at least they gave me that ability, they gave

H. Sharma et al. / Physiotherapy 98 (2012) 336–343 339

Table 2
Definitions of themes and categories.

Product of data analysis Definition Example

1st level themes An interpretation of descriptive information (age, ethnicity,
etc.) and coding (labelling text according to subject); a
reflection on meaning

Specific text was grouped, according to how participants
viewed relationships with the physiotherapist. These were
further labelled to reflect the interpretation that some text
focused on the ‘personal service’ from the physiotherapist, and
other text described experiences of ‘partnership’ – these were
designated 1st level themes

2nd level themes Relationships between first level themes Further analysis of ‘personal service’ revealed that it was
linked to participants’ observations of the personal qualities of
the physiotherapist. These relationships formed 2nd level
themes, e.g. ‘A personal service linked to the physiotherapist’s
caring quality’

3rd level
themes/categories

Collections of second level themes united by a central idea The idea of ‘confidence’ transcended many 2nd level themes
and their components. ‘Confidence’ linked related ideas,
including ‘the physiotherapist’, ‘the group’, ‘social situations’,
‘the rehabilitation setting’

Master theme A general pattern or overarching theme that is illustrated by “ERS as a catalyst for regaining independence”. Categories

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several categories

e that push . . . So thereafter, I just cook up something in my
ead, go down the stairs or go down the street.’ [Louise]

Increased activity generated feelings of normality and
ndependence:

Because when I do exercise, when I go out, it puts me back
o normal. And when I see others walking, what would make
e not walk? I am not disabled. The stroke has not made me
isabled, so I walk.’ [Mary]

mprovement
Participants identified improvements following ERS par-

icipation, predominantly in fitness, strength and movement:

If I didn’t go [to the exercise referral scheme] . . . it would
ake a long time for me to be moving around . . . I gained more
trength . . . [the exercise referral scheme] really helped my
oving, my walking, how I am doing everything.’ [Beth]

Several participants also identified ‘immediate’ improve-
ents to mood following the exercise sessions, perceived as

vidence that the stroke was ‘going away’ and that they were
getting better’. Positive feelings of happiness and enjoyment
ere described, and exercise became a source of pleasure in

tself:

When I finish exercising and I feel so good, so content. . . By
he end of the day you feel good, you know, you say ‘I feel
ood, my health is coming back’ in your head.’ [Peter]

ontrol
Interestingly, participants attributed perceived improve-

ents during initial rehabilitation to external factors, such as
he physiotherapist, God, the consultant, or the health service
n general, and perceived themselves as dependent:

When I’d gone walking, I’d always had somebody from the
ard going out with me and holding me up, or I was in the
heelchair and I hated it.’ [Jim]

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were seen as personal benefits of the ERS that were connected,
contributing to greater normality and independence

When recalling ERS participation, interviewees expressed
he importance of their own personal qualities to successful
ecovery and increasing independence, attributing improve-
ents to internal factors such as motivation, willpower and

elf-determination:

The physio is something else, the exercise programme is
omething else, you yourself willing to do something for your-
elf, and having that willpower to proceed and progress what
ou want to do is another thing.’ [Louise]

onfidence
Low confidence was described as a barrier in relation to

nitial ERS attendance. Attitudinal barriers in the form of
eservations about the gym environment were described, as
ell as physical barriers en route from home to the leisure

entre.

My own sense of . . . my self-esteem was very low anyway,
he fact that I couldn’t physically do things I used to take
or granted, and I don’t particularly like that kind of macho
ulture anyway. I wouldn’t want to expose myself to it. I’d
ave been worried about people poking fun.’ [Tony]

Initially when I was discharged from hospital, I want to go
o the gym. When I come out from my house and I look at the
tairs, it’s like I want to fall over, I go back inside and shut
he door.’ [Louise]

Confidence that was specifically related to exercise
ncreased within the ERS, facilitated by the physiotherapist
nd group dynamic:

I mean me, all I can say is that I had determination. I didn’t
ave the confidence, but I had determination and they [phys-
otherapists] gave me the confidence. But when I saw I could

tart to do a thing, that was it. Once I got to start doing it I
ooked at my sheet and saw I did that little bit more than last
eek.’ [Jim]

340 H. Sharma et al. / Physiotherapy 98 (2012) 336–343

Table 3
An overview of the master theme and contributing categories and themes.

Master theme Constituent categories and definitions Second level themes contributing to the category

‘ERS as a catalyst for regaining
independence’

1a. Exercise engagement: behavioural changes
regarding exercise

1ai. Links between confidence and exercise engagement

1aii. Links between physical improvement and exercise
engagement
1aiii. Exercise engagement and perceived exercise restrictions
or opportunities
1aiv. Reflections on the self and exercise engagement

1b. Control: participants’ changing views on who/what
was responsible for them gaining independence

1bi. Links between the rehabilitation setting and perceptions of
control
1bii. Varying roles of the physiotherapist
1biii. Perceptions of control and exercise behaviour
1biv. Perceptions of control and the discharge procedure

1c. Confidence: the progression of feelings of
self-confidence and beliefs in exercise ability

1ci. Links between the rehabilitation setting and confidence

1cii. Links between perceptions of the physiotherapist and
confidence
1ciii. Links between perceptions of the group and confidence
1civ. Links between independence, emotions and confidence
1cv. Confidence and social situations

1d. Improvement: Physical and psychological
improvements and their meanings to participants

1di. Links between improvement and beliefs about the exercise
programme
1dii. Links between improvement and beliefs about exercise
generally

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Increased confidence also affected more general social and
ccupational activities:

I was ashamed, limping all the time and using a walking
tick. But when I got there, I saw people that were even older
nd even younger than me and they were there for numerous
easons. And these are people that say, when we finish using
he gym, ‘I am going to the high street for window shopping’,
nd I tag along. . . At times, I just walk into the shopping
entre with confidence. . ..’ [Louise]

One participant expressed a belief that the ERS con-
ributed to increased confidence, and felt able to return to
ork:

I started work and I was able to start where I left off. . .
nd if I had not gone through this I would not have had the
onfidence. . . It is not the medication that has made me better,
t is the exercise. . .’ [Peter]

aster theme

The categories emerging from the data describe a jour-
ey through engagement with exercise after stroke, yielding
hysical and psychological improvements, increased feelings
f personal control, and raised confidence. These personal
evelopments appeared to be linked in their contributions to
egaining independence. Thus, the master theme that emerged

as entitled: ‘ERS as a catalyst for regaining independence’.
These results are summarised in Table 3, demonstrating

he audit trail from second level themes, through categories,
o the master theme.

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1diii. Links between beliefs and feelings about exercise
1div. Impacts of beliefs and feelings about exercise on exercise
engagement

iscussion

ain findings

The findings from this study suggest that the ERS encour-
ged participants to become more active within and outside
he sessions. Participants reported physical and psycholog-
cal improvements, including fitness, strength, movement,

ood and enjoyment. Locus of control appeared to shift
rom predominantly external during initial rehabilitation,
o more internal during the ERS. Initial barriers to exer-
ise participation had to be overcome, including concerns
bout getting to the venue, low self-confidence, and feelings
f self-consciousness. Generic and PA-specific self efficacy
ncreased, and the group format appeared to induce feelings
f independence and normality.

Reduced independence is a key problem after stroke with
wo thirds of people experiencing limitations in at least one
ctivity of daily living five years after stroke [39]. The current
tudy revealed that participants had been involved in a slow
rocess of regaining independence, in which the ERS acted
s a catalyst, enhancing perceptions of greater normality,
onfidence and independence.

These findings contribute to the literature on exercise after
troke; one systematic review highlighted the lack of research
elating to effects of exercise on disability, dependence,
ood, self-efficacy and locus of control [10]. The current

ndings resonate with other qualitative work, where stroke
urvivors reported that exercise enhanced physical function,
mpowerment and confidence [27,29]. When looking beyond

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H. Sharma et al. / Phys

iterature specific to stroke, the significance of ERS participa-
ion was also identified by one study in an ageing population
nd one in people with mental ill-health [40,41]. Recovery of
lements of the self was described, as participants were said
o ‘reconnect with their human potential’ [40] and ‘reclaim a
ense of personhood’ [41]. This may be particularly important
or stroke survivors who have experienced dramatic changes
n their physical, emotional and social worlds. In the current
tudy, one participant reported feeling ‘completely lost . . .
he stroke took my life away from me; everything I could do,
verything that meant anything to me’ [David]. Evidently,
uch qualitative data deepen our understanding of the impact
f exercise on the self as a whole.

All consenting participants in this study experienced pos-
tive changes in their physical and psychological well-being,
ome up to four years post-stroke. This supports UK national
linical guidelines for stroke [12–14], which advocate the
romotion of an active lifestyle where possible. The ERS
rovides one strategy to this effect and further collabora-
ion between physiotherapy and local health and leisure
ervices is required to facilitate access to exercise after stroke
14,42–44].

mplications of findings for exercise after stroke referral
chemes

Service development requires evidence of efficacy, and
xisting ERSs have been criticised for using primarily
mpairment-orientated outcomes (e.g. blood pressure), and
eing insufficiently client-centred [18]. The current study
uggests that ERS evaluation would benefit from addi-
ional measures relating to mood, self-efficacy and locus of
ontrol.

Low recruitment and attendance must also be addressed
34]. A survey found that the three most common barriers
o exercise after stroke were programme cost, lack of trans-
ortation and lack of knowledge about local exercise facilities
45]. In the current study, some participants said they were
ncomfortable around able-bodied exercisers, which could
e exacerbated in a gym setting where the focus is often
n physical perfection. To reduce perceived barriers to exer-
ise after stroke, opportunities to exercise in a peer group and
olutions for environmental barriers (e.g. providing transport)
hould be offered where possible, as recommended in the best
ractice guidelines [44].

tudy limitations

The credibility of the data must be considered. The sam-
le was small, with a low response rate, possibly due to
ecruitment by mail. Although not ideal, this was approved on
thical review. However, the sample was consistent with the

tudy design and aims of increased depth of insight that can
e transferred to similar contexts, rather than generalisabil-
ty of results [46]. Data were extensive, with 45–80 minutes
f interview per participant. While data saturation through
A
b

py 98 (2012) 336–343 341

epeated interviews was not possible within the scope of the
tudy, analytical saturation was achieved [46].

The sample was not necessarily representative of the
ider stroke population, with varied demographic charac-

eristics and a low mean age, which may have affected
RS uptake. Similar positive perspectives on ERS partici-
ation were expressed, which may have been influenced by
ocial desirability and convenience sampling. The views of
hose who did not accept an invitation to the ERS were not
ddressed, and future research should use purposive sam-
ling to explore successful and unsuccessful experiences. It
ould also be valuable to collect data relating to time since
articipation and frequency of participation.

The ethnic diversity was representative of the local area
47], but in some cases, vocabulary and expression may have
ffected interpretation of responses. A field diary was used in
rder to reflect on possible influences during data collection
nd analysis.

There were insufficient resources to provide communica-
ion support, and regretfully, persons with memory impair-

ents or communication difficulties were therefore excluded,
s is frequently the case. The resulting bias is acknowledged.

Five out of nine participants returned and agreed with the
nterview summaries, enhancing credibility of initial inter-
retation. Respondent validation of the final themes was
onsidered less useful because not all themes related to the
iews of every participant [48]. Although the lack of verifica-
ion of four summaries limits credibility, it was not considered
thical to pursue the missing summaries. On balance, the
esults have credibility and were generated through a rigor-
us process. The relevance of these findings to further settings
ust be evaluated by the reader, using the contextual and

emographic information provided [32].

onclusions

This study aimed to explore stroke survivors’ experiences
f exercise in the context of a community-based ERS. Par-
icipants perceived the scheme as an important driver in
he process of regaining independence, as they experienced
mprovements in physical and psychological function. They
lso reported a shift from an external to a more internal locus
f control and improved general and exercise-specific self-
fficacy, which carried over into activity outside the exercise
essions. The findings from this – albeit small-scale – study
upport exercise referral schemes as a method for increas-
ng physical activity after stroke. However, some barriers
o exercise participation also emerged, and further research
s required to explore how uptake and continued exercise
ngagement after stroke can be optimised.

cknowledgements

The following are gratefully acknowledged: the contri-
ution of the study participants, and the assistance of Helle

3 iothera

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42 H. Sharma et al. / Phys

ampson (Clinical Lead Physiotherapist, Southwark Primary
are Trust) with the pilot interview.

thical approval: King’s College Hospital Research Ethics
ommittee (Ref. No. 06/Q0703/210) and Queen Margaret
niversity, Subject Area Ethics Panel, no ref. number.

onflict of interest: The authors report that there were no
onflicts of interest.

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Experiences of an exercise referral scheme from the perspective of people with chronic stroke: a qualitative study

Introduction
Method
Study design
Sample population and recruitment
Procedure
Data analysis
Results
Participant characteristics
Categories
Exercise engagement
Improvement
Control
Confidence
Master theme
Discussion
Main findings
Implications of findings for exercise after stroke referral schemes
Study limitations
Conclusions
Acknowledgements
References

Non-experimental
(observational) designs

Neil O’Connell
PH2600 Research Methods

Learning

outcome

s
By the end of the lecture students should
be able to:

 Describe basic common observational
study designs

 Describe the concept of correlation

 Consider some of the biases that we
attempt to control for

It’s a complex world

 Clinical phenomena
and human behaviour
are complex

 Research seeks to
unravel the
complexity

 But experiments are
often not possible or
appropriate…
because…

Many naturally occurring
variables can’t be

manipulated

Many variables shouldn’t
be manipulated (ethics)

The research question
does not require
manipulation of

variables (descriptive/
exploratory)

Experiments are simply
not feasible

DESCRIBE THE
CHARACTERISTICS

OF A CERTAIN
GROUP

DRAW
COMPARISONS

BETWEEN
DIFFERENT
GROUP

ANALYSE
RELATIONSHIPS

BETWEEN NATURALLY
OCCURRING VARIABLES

(CORRELATIONAL
DESIGN)

INVESTIGATE THE
INFLUENCE OF

VARIABLES THAT
CANNOT BE

EXPERIMENTALLY
MANIPULATED

INVESTIGATE THE
NATURAL COURSE
OF A CONDITION

INVESTIGATE RISK
FACTORS FOR A

CERTAIN

OUTCOME

Researchers might want to….

Hierarchy of study design

Experimental &
quasi-experimental

studies

Systematic reviews (+/- meta-
analysis)

Randomised Controlled Trial (RCTs)

Controlled clinical trials

Observational
studies

Cohort

Case-control

Cross-sectional

Case-report, case-series
Expert opinion etc.

Generate
hypotheses

Establish
causality

Descriptive

Describe the sample
characteristics,

behaviours,
conditions

Exploratory/ Analytical

Systematically
investigate relationships

between variables

Hypothesis-driven

Correlational designs

Correlation designs

Analysis of relationships:

correlation research to understand:

1. Whether patterns exist within data.

2. Whether and how variables are related.

Correlation
 Variables often co-vary

 A variable rises or lowers in relation
to the behaviour of another variable

 These variables might be described as
“related” or “associated” with one
another

 We measure these associations
statistically

The problem of causality

www.xkcd.com

Study
Population

Cross-sectional

Prospective Retrospective

Longitudinal

Basic model

• aim is to measure (quantify) the relationship between
exposure &

outcome

• cannot determine whether causal link – need experimental
design

EXPOSURE

Risk factor

Determinant

Treatment

OUTCOME

Disease

Mortality

Health

Cross-sectional studies

• Simplest form of observational study

• Describes population at one point in time
‘snapshot’

• Exploration of factors associated with a

disease

or condition (risk and/or protective factors)

• Can compare subgroups within a

population

Typical research question
“What proportion of the population have characteristic x?”

Typical cross sectional study
questions

What are the
characteristics of this

population?

What proportion of the
population have
characteristic X?

What variables are
related to

characteristic X

Do people with
characteristic X differ
from those who don’t?

Important to consider the temporal association
between exposure & outcomes

PAST

PRESENT FUTURE

EXPOSURE
+ OUTCOMEEXPOSURE

X sectional study

TIME

Cross-sectional study: example
Elliot et al. Lancet 1999, 354: 1248-52

Research question: what proportion of the general
population in North East Scotland have chronic pain?

Sample:
– random sample of adults registered with GP in
Grampian region (~5000)
– stratified sample by age & sex

Method: Postal self-completion questionnaire, chronic
pain grade questionnaire , standard definitions

Results: 46% popn had chronic pain, major problem in
general practice

Cross-sectional studies

Strengths

– quick to conduct, relatively cheap

– allows exploration of multiple risk factors

– useful to assess health needs of population

– useful first step: hypothesis generating – may

provide clues & justification for further

investigation

Cross-sectional studies

Weaknesses

– selection bias (selection of sample, responders etc)

– cannot prove cause – single point in time
(snapshot)

Cohort studies

• Observes people over time
– can be for weeks, months or years

• Exposures (agents/risk factors) & outcomes are
recorded

 Purpose
 To understand the natural history of a disease
 To evaluate long-term patient health or quality of

life
 Analyse the relationship between risk factors &

disease

Cohort studies
Cohort = group of people who share common
exposure (e.g. year of birth)

= Latin legion of soldiers

• E.G. start with people without the disease, document
exposures, follow through time

• Includes those with & without risk factors

• Determines incidence (new cases) of disease

Research question
Whether exposure to factor ‘x’ leads to disease ‘y’?

OUTCOME PRESENT

NO OUTCOME

OUTCOME PRESENT
NO OUTCOME

PO
PU

LATIO
N
O
F IN

TER

EST

PRESENT FUTURE

MEASURE
EXPOSURE (S) AT

BASELINE

EXPOSED

NOT EXPOSED

MEASURE
OUTCOMEOF
INTEREST

SAMPLE

HEALTHY
GROUP

ACUTE
DISEASE

WHO
DEVELOPES
DISEASE?

WHO
RECOVERS?

WHO
BECOMES
CHRONIC?

CHRONIC
DISEASE

WHO
RECOVERS?

INCEPTION COHORT

‘Landmark’ cohort studies


UK Doctors Cohort Study

(1950s)
– 40,000 UK doctors

 USA Nurses Cohort Study (mid-1970s) >121,700
female nurses (Oral contraceptive and breast Ca)

 UK Oral Contraceptive Pill cohort study(1968 –
present)

– 46,000 women , all cause mortality

 women >50 years (1 in 4 women in UK) HRT, Ca,
other disease

UK Doctors Cohort Study

CAUSE‐SPECIFIC
MORTALITY (LUNG CA)

ALIVE/ DEAD OF OTHER
CAUSE

CAUSE‐SPECIFIC
MORTALITY (LUNG CA)
ALIVE/ DEAD OF OTHER
CAUSE

1950 2001

MEASURE
EXPOSURE (S)

TOBACCO
USE

NO TOBACCO

MEASURE
OUTCOMEOF
INTEREST

UK
DOCTORS

Tobacco & mortality
1951: Smoking questionnaire from 40,000 British doctors
(Doll & Hill)

Assessed: 1951, 1957, 1966, 1971, 1978, 1991, 2001….

Analysis
• Excess mortality in smokers
• Reversal of effect in ex-smokers
• Other diseases eg IHD, respiratory disease, CVD, bladder

cancer, etc.

BMJ paper, Doll et al. 2004:

cessation at age 30 gain 10 years life expectancy
age 40 gain 9 yrs
age 50 gain 6 yrs
age 60 gain 3 yrs

Dose-response relationship

– evidence for causality (one of Bradford-Hill’s criteria)

Strengths of cohort design

• Can directly estimate risk and relative risk of disease in
a population

• Can determine the natural history of a condition

• Can calculate incidence

• Can demonstrate temporal sequence

• Analysis of many different exposures/outcomes

• Less prone to bias than case-control and x-sectional

studies

ATTRITION

BIAS

e.g. loss to follow
up (not at
random)

SELECTION BIAS

e.g.
unrepresentative

population

MEASUREMENT OR
CLASSIFICATION

BIAS

e.g. poor
standardisation,

unblinded
assessors, changes

in diagnostic
criteria

Weaknesses of cohort studies

Case-control studies
 Start with people with disease [outcome]

Two groups:
– Cases those with disease
– Controls those without disease

 Collect data on risk factors [exposures] of
interest

 Compare odds of exposure in two groups


Research question

“ Are those with disease “x” more likely, than those without
disease x, to have been exposed to risk factor “y”?

Key features

• Observational design ~ hypothesis generating

• Identification of subjects with disease X (or other
outcome of interest)

• Identification of suitable control group without
disease X

• For both groups, past exposure is then determined

• Retrospective or historical in nature of enquiry

CASES
(with disease)

CONTROLS
(disease free)

RISK FACTOR

NO RISK FACTOR

RISK FACTOR
NO RISK FACTOR
PO
PU

LAT
IO

N
O

F IN
T
ER

EST

PAST PRESENT

DIRECTION OF ENQUIRY (RETROSPECTIVE)

Historical example: case-control study

• 1960—1961 in Hamburg,
obstetricians noted 27 infants
born with severe malformations

• Rare condition, no cases
observed between 1930–1958

• German study recruited
mothers of affected infants &
sample of mothers of healthy
infants

• Detailed investigation of
behaviours & practices during
pregnancy; documentation of
multiple exposures in both
groups of women

Historical example: case-control study

• Identified higher use of drug thalidomide in cases

• Sleeping pill introduced in late 1950s, safer than
barbiturates – did not induce coma

• Prescribed for pregnant women, anti-emetic taken
between 27–40th week of pregnancy

• Drug had been used in 46 countries – led to overhaul of
drug development & licensing, withdrawn 1961

• http://www.guardian.co.uk/society/2012/sep/01/thali
domide-cover-up

Mothers of babies
with birth

abnormalities
(n=100)

Mothers of healthy
babies
(n=200)

Thalidomide

No Thalidomide

Thalidomide
No Thalidomide

SA
M

P
LE

O
F
M

O
T

H
E
R

DIRECTION OF ENQUIRY (RETROSPECTIVE)

OUTCOME (DISEASE)EXPOSURE

Selection of cases & controls
Most critical stage in a case-control study

Selection of cases
– clearly define ‘cases’
– specify inclusion & exclusion criteria
– where is the ‘source’ population? e.g. residents from
geographical region, patients recruited from a hospital ward
or clinic.

Selection of controls
– same source as the cases
– random selection of controls from source population
– or matching (age, sex, SE status…..)
– increase comparator group e.g. >2 controls : 1 case

Case-control contd.

Data collection & measurement

Collecting information about the past…
– questionnaires / face to face interviews
– GP or hospital records
– medical examination
– occupational records
– or other previously collated data e.g. blood
tests, biological markers

– May be missing or incomplete

Strengths of case-control design

• Very useful for investigating rare diseases or
diseases with a long induction period e.g. some
cancers

• Time and cost efficient – when compared to
cohort studies

• Existing records /database can be used

• Permits investigation of multiple risk factors
/exposures

Weaknesses: case control

SELECTION BIAS
(poor case

definition, difficult
finding

representative
controls)

RECALL BIAS
(incomplete,

unreliable recall of
past events,

incomplete records,
worse without

blinding)

OBSERVER BIAS
(awareness of
hypothesis,
exposure or

outcome status)

CONFOUNDER BIAS
(controls not
matched on
important

variables, or
unknown variables

not included in
analysis)

VERY PRONE TO
SYSTEMATIC ERROR

EFFICIENT BUT
VULNERABLE

Study designs

Always consider the timeline

temporal association between exposure &
outcomes

past present future

Case control

Cohort

Cross sectional

exposure

exposure
outcome
outcome

Exposure
&

outcome

Confounding:

The weakness of all non-
randomised studies

Confounding may increase/decrease or
totally manufacture any observed effect.

How to control for confounding:

 Prevent at design stage:
◦ – restrict, randomly select, match

 Deal with at analysis stage:
◦ – stratification, multivariate modelling
◦ but only for things you know about

TEMPORAL
SEQUENCE?

STRENGTH OF

ASSOCIATION?

CONSISTENCY
OF

ASSOCIATION?

BIOLOGICAL
GRADIENT

(DOSE
RESPONSE)?

SPECIFICITY OF
ASSOCIATION?

BIOLOGICAL
PLAUSIBILITY?

COHERENT WITH
EXISTING

KNOWLEDGE?

Experimental
evidence
(RCT?)

Causality: Bradford Hill Criteria

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