Duncan Critchley - Academia.edu (original) (raw)

Papers by Duncan Critchley

BMJ open sport & exercise medicine, 2016

People with chronic low back pain (CLBP) demonstrate greater postural instability compared with a... more People with chronic low back pain (CLBP) demonstrate greater postural instability compared with asymptomatic individuals. Rocker-sole shoes are inherently unstable and may serve as an effective balance training device. This study hypothesised that wearing rocker-sole shoes would result in long-term improvement in barefoot postural stability in people with CLBP. 20 participants with CLBP were randomised to wear rocker-sole or flat-sole shoes for a minimum of 2 hours each day. Participants were assessed barefoot and shod, over three 40 s trials, under 4 posture challenging standing conditions. The primary outcome was postural stability assessed by root mean squared error of centre of pressure (CoP) displacement (CoPRMSE AP) and mean CoP velocity (CoPVELAP), both in the anteroposterior direction, using force plates. Participants' were assessed without knowledge of group allocation at baseline, 6 weeks and 6 months (main outcome point). Analyses were by intention-to-treat. At 6 mont...

Archives of Physical Medicine and Rehabilitation, Nov 1, 2008

Endleman I, Critchley DJ. Transversus abdominis and obliquus internus activity during Pilates exe... more Endleman I, Critchley DJ. Transversus abdominis and obliquus internus activity during Pilates exercises: measurement with ultrasound scanning. Arch Phys Med Rehabil 2008;89:2205-12. Objective: To assess activity of transversus abdominis (TrA) and obliquus internus abdominis (OI) muscles during classical Pilates exercises performed correctly and incorrectly, and with or without equipment.

Rheumatology, Apr 1, 2014

and refined using Nominal Group Technique. Comparator groups confused with IIM were defined. Data... more and refined using Nominal Group Technique. Comparator groups confused with IIM were defined. Data collection: Within this retrospective case control study, clinical and laboratory data from IIM and comparator patients were collected from 47 rheumatology, dermatology, neurology and pediatrics clinics worldwide from 2008-2011. Data for external validation analysis were extracted from the UK juvenile myositis register. Analysis: Crude pair-wise associations among all variables measured and between each variable and clinician's diagnosis were assessed. Three approaches for derivation of classification criteria were explored: (i) Traditional: case defined by specified number of items from a set; (ii) Risk score: patient assigned a probability risk score by summing score-points associated with the variables (Probability model 1 and 2); (iii) Classification tree: case defined by a decision tree. A random forest algorithm explored the most important variables. Results obtained with each approach were utilized to improve others iteratively. Validation: Internal validation using bootstrap methods was performed. External validation using extracted data from an UK juvenile myositis register was performed. Results: Data from 973 IIM patients (74% adults; 26% children), representing subgroups of IIM (245 polymyositis, 239 dermatomyositis, 176 inclusion body myositis and 246 juvenile dermatomyositis cases) and 629 comparators (81% adults; 19% children) were obtained. The comparators include other myopathies and systemic rheumatic diseases. Two probability score models were developed: Model 1 comprised clinical variables on muscles, skin, and laboratory measures; Model 2 additionally comprised muscle biopsy variables. Model 1 performed nearly as well as Model 2 and both models performed as well as and often better than, the classification tree that was developed and published criteria. External validation using data on 332 juvenile myositis cases resulted in 100% sensitivity of the probability model. Conclusion: New classification criteria for IIM with readily clinically assessable measurements and symptoms have been developed. They generally show superior performance compared with existing criteria. Disclosure statement: C.A.P. has served as a consultant for UCB and Pfizer; and has received grants/research support from Arthritis Research UK. J.A.S. has served as a consultant for Savient, Takeda, Regeneron and Allergan; has received grants/research support from Takeda and Savient; and is an Omeract executive. All other authors have declared no conflicts of interest.

BMJ Open, 2016

Chronic low back pain (CLBP) is a common condition and source of significant suffering, disabilit... more Chronic low back pain (CLBP) is a common condition and source of significant suffering, disability and healthcare costs. Current physiotherapy treatment is moderately effective. Combining theory-based psychological methods with physiotherapy could improve outcomes for people with CLBP. The primary aim of this randomised controlled trial (RCT) is to evaluate the efficacy of Physiotherapy informed by Acceptance and Commitment Therapy (PACT) on functioning in patients with CLBP. The PACT trial is a two-armed, parallel-group, multicentre RCT to assess the efficacy of PACT in comparison with usual physiotherapy care (UC). 240 patients referred to physiotherapy with CLBP will be recruited from three National Health Service (NHS) hospitals trusts. Inclusion criteria are: age ≥18 years, CLBP ≥12-week duration, scoring ≥3 points on the Roland-Morris Disability Questionnaire (RMDQ) and adequate understanding of spoken and written English to participate. Patients will be randomised to PACT or UC (120 per arm stratified by centre) by an independent randomisation service and followed up at 3 and 12 months post randomisation. The sample size of 240 will provide adequate power to detect a standardised mean difference of 0.40 in the primary outcome (RMDQ; 5% significance, 80% power) assuming attrition of 20%. Analysis will be by intention to treat conducted by the trial statistician, blind to treatment group, following a prespecified analysis plan. Estimates of treatment effect at the follow-up assessments will use an intention-to-treat framework, implemented using a linear mixed-effects model. This trial has full ethical approval (14/SC/0277). It will be disseminated via peer-reviewed publications and conference presentations. The results will enable clinicians, patients and health service managers to make informed decisions regarding the efficacy of PACT for patients with CLBP. ISRCTN95392287; Pre-results.

Disability and rehabilitation, Jan 10, 2016

Purpose To translate and cross-culturally adapt the Back Beliefs Questionnaire (BBQ) into modern ... more Purpose To translate and cross-culturally adapt the Back Beliefs Questionnaire (BBQ) into modern standard Arabic and examine its validity, acceptability and reliability in Arabic-speaking patients with low back pain (LBP). Method The BBQ was forward, back-translated and reviewed by an expert committee. Seventeen bilingual patients completed Arabic and English BBQs. LBP patients (n = 199) completed the Arabic BBQ. Sixty-four repeated it a week later, and 151 completed the Arabic Fear-avoidance Beliefs Questionnaire (FABQ). Results The expert committee followed advice from the developers to maintain Arabic equivalence of "back trouble(s)". Patients found the questionnaire comprehensible and acceptable. Agreement between the English and Arabic versions of the BBQ was acceptable, ICC = 0.65 (0.25-0.86). Most item-by-item agreement ranged from fair to moderate (K = 0.12-0.54). Mean (SD) of BBQ, FABQ total, work and physical activity subscales were 25.31(6.13), 44.76(19.49), 21...

SPINE, 2016

Systematic review. To review the evidence regarding the mechanism of action of mobilizations. Spi... more Systematic review. To review the evidence regarding the mechanism of action of mobilizations. Spinal mobilizations-low velocity passive oscillatory movements-reduce spinal pain in some patient subgroups. Identifying patients likely to respond remains a challenge since mobilizations' mechanism(s) of action are unclear. Medline, Web of Science, Cinahl, Embase, and Scopus databases were searched for relevant studies. Reference lists of included studies were hand searched. Studies were included if the intervention was passive spinal mobilizations, participants were symptomatic, and outcomes evaluated possible mechanisms of action. Methodological quality was independently assessed by two assessors using a modified Cochrane Back Review Group tool. Twenty-four studies were included in the review. Four were classified high risk, 14 moderate risk, and four low risk of bias. Commonest methodological limitations were lack of participant blinding, adequate randomization and allocation concealment, and sample size calculation. Evidence suggests that spinal mobilizations cause neurophysiological effects resulting in hypoalgesia (local and/or distal to mobilization site), sympathoexcitation, and improved muscle function. Mobilizations have no effect on temperature pain threshold. Three of four studies reported reduction in spinal stiffness, heterogeneous in location and timing. There is limited evidence (one study in each case) to suggest that mobilizations produce increased nociceptive flexion reflex threshold, improved posture, decreased concentration of substance P in saliva, and improved sway index measured in cervical extension. Evidence does not support an effect on segmental vertebral movement. Two studies investigated correlations between hypoalgesia and mechanism: one found a correlation with sympathoexcitatory changes, whereas the other found no correlation with change in stiffness. These findings suggest involvement of an endogenous pain inhibition system mediated by the central nervous system, although this is yet to be investigated directly. There is limited evidence regarding other possible mechanisms. 3.

Rheumatology, Apr 1, 2014

them all. The relationship between process and experience (how young people feel about it) is not... more them all. The relationship between process and experience (how young people feel about it) is not clear-cut. Both process and experience vary, but not directly in parallel. Our data offer an explanation for this: that reported experience is informed by features of both the past and the present. Important factors seem to be: the young person's orientation to change; the correspondence between the actual and expected decision-making process; and how-at the time of interview-young people are finding treatment itself. Conclusion: Service type (paediatric, young adult, or adult) is a predictable determinant of process, but which might neverthelessfrom the point of view of equity-warrant further scrutiny and discussion. However, it is not the only thing that shapes process. Moreover it is evident that process alone does not determine young people's experience. Underpinning all the factors informing young people's experience is communication with and from health professionals-about why the decision should be made, what the process will involve (in particular when the decision point will come) and how, post-decision, they find treatment itself. Fine-tuning communication on these matters may help more young people to reflect positively on an inevitably complex decision. Disclosure statement: The authors have declared no conflicts of interest.

Spine, 2014

Cross-cultural translation, adaptation, and psychometric testing. To cross-culturally translate a... more Cross-cultural translation, adaptation, and psychometric testing. To cross-culturally translate and adapt the Roland-Morris Disability Questionnaire (RMDQ) into Modern Standard Arabic and examine its validity with Arabic-speaking patients with low back pain (LBP). The English RMDQ is valid, reliable, and commonly used to assess LBP disability in clinical practice and research. There is no valid and reliable version of the RMDQ in Modern Standard Arabic. The RMDQ was forward translated and back translated. An expert committee of musculoskeletal physiotherapists reviewed the translation. Eight patients with LBP evaluated item-by-item comprehensibility. Ten patients piloted the RMDQ for overall comprehensibility and acceptability. Seventeen bilingual patients tested the agreement of the Arabic and English RMDQs. Two-hundred one patients completed the RMDQ and the visual analogue scale. Sixty-four patients were followed-up for test-retest reliability. Translation of most items was uncontroversial. The expert committee found the Arabic RMDQ clinically and culturally appropriate. They reviewed item 11, addressing bending and kneeling, because this has a clinical significance and cultural/religious implication regarding prayer positions. All patients reported that it was easy to understand and complete. The Arabic RMDQ had high overall agreement with the English RMDQ for the global score (intraclass correlation coefficient [ICC] = 0.925; 0.811-0.972). Kappa statistics showed good item-by-item agreement (none ≤0.30). Mean (SD) RMDQ and visual analog scale scores of 201 patients were 10.53 (4.80) and 5.11 (2.28), respectively. The RMDQ had a low correlation against pain intensity (r = 0.259; P < 0.01). A Cronbach α of 0.729 showed high internal consistency. Test-retest reliability of the Arabic RMDQ was good (ICC = 0.900; 95% confidence interval, 0.753-0.951). Kappa statistics were high for 18 items and fair for 6. The Arabic version of the RMDQ has good comprehensibility and acceptability, high internal consistency and reliability, low correlation against pain intensity, and good agreement with the English RMDQ. We recommend its use with Arabic-speaking patients with LBP. 3.

Spine, 2013

Multicenter, assessor-blind, randomized, clinical trial. To compare the effectiveness of rocker s... more Multicenter, assessor-blind, randomized, clinical trial. To compare the effectiveness of rocker sole footwear to traditional flat sole footwear as part of the management for people with low back pain (LBP). During the past decade, persistent advertising has claimed that footwear constructed with a rocker sole will reduce LBP. However, there is no robust evidence to support these claims. One hundred fifteen people with chronic LBP were randomized to wear rocker sole shoes or flat sole shoes for a minimum of 2 hours each day while standing and walking. Primary outcome was the Roland Morris Disability Questionnaire (RMDQ). In addition, participants attended an exercise and education program once a week for 4 weeks and wore their assigned shoes during these sessions. Participants were assessed without their knowledge of group allocation prerandomization, and at 6 weeks, 6 months, and 1 year (main outcome point). Analysis was by intention-to-treat method. At 12 months, data from 44 of 58 (77.2%) of the rocker sole group and 49 of 57 (84.5%) of the flat sole group were available for analysis. In the rocker sole group, mean reduction in RMDQ was -3.1 (95% CI [confidence interval], -4.5 to -1.6), and in the flat sole group, it was -4.4 (95% CI, -5.8 to -3.1) (a greater negative value represents a greater reduction in disability). At 6 months, more people wearing flat shoes compared with those wearing rocker shoes demonstrated a minimal clinically important improvement in disability (53.2% and 31.1%, respectively; P = 0.03). Between-group differences were not significant for RMDQ or any secondary outcomes (e.g., pain) at any time. People reporting pain when standing and walking at baseline (n = 59) reported a greater reduction in RMDQ at 12 months in the flat sole group (-4.4 [95% CI, -6.0 to -2.8], n = 29) than the rocker sole group (-2.0 [95% CI, -3.6 to -0.4], n = 30) (P < 0.05). Rocker sole shoes seem to be no more beneficial than flat sole shoes in affecting disability and pain outcomes in people with chronic LBP. Flat shoes are more beneficial for LBP aggravated by standing or walking. N/A.

Spine, 2007

Pragmatic, randomized, assessor blinded, clinical trial with economic analysis. To compare the ef... more Pragmatic, randomized, assessor blinded, clinical trial with economic analysis. To compare the effectiveness and cost-effectiveness of three kinds of physiotherapy commonly used to reduce disability in chronic low back pain. Physiotherapy reduces disability in chronic back pain, but there are several forms of physiotherapy and it is unclear which is most effective or cost effective. A total of 212 patients referred to physiotherapy with chronic low back pain were randomized to receive usual outpatient physiotherapy, spinal stabilization classes, or physiotherapist-led pain management classes. Primary outcome was Roland Disability Questionnaire score 18 months from baseline; secondary measures were pain, health-related quality of life, and time off work. Healthcare costs associated with low back pain and quality-adjusted life years (QALYs) were also measured. RESULTS.: A total of 71 participants were assigned to usual outpatient physiotherapy, 72 to spinal stabilization, and 69 to physiotherapist-led pain management. A total of 160 (75%) provided follow-up data at 18 months, showing similar improvements with all interventions: mean (95% confidence intervals) Roland Disability Questionnaire score improved from 11.1 (9.6-12.6) to 6.9 (5.3-8.4) with usual outpatient physiotherapy, 12.8 (11.4-14.2) to 6.8 (4.9-8.6) with spinal stabilization, and 11.5 (9.8-13.1) to 6.5 (4.5-8.6) following pain management classes. Pain, quality of life, and time off work also improved within all groups with no between-group differences. Mean (SD) healthcare costs and QALY gain were pound474 (840) and 0.99 (0.27) for individual physiotherapy, pound379 (1040) and 0.90 (0.37) for spinal stabilization, and pound165 (202) and 1.00 (0.28) for pain management. For chronic low back pain, all three physiotherapy regimens improved disability and other relevant health outcomes, regardless of their content. Physiotherapist-led pain management classes offer a cost-effective alternative to usual outpatient physiotherapy and are associated with less healthcare use. A more widespread adoption of physiotherapist-led pain management could result in considerable cost savings for healthcare providers.

Manual Therapy, 2006

The purpose of this study was to consider how the deep abdominal muscles responded to alterations... more The purpose of this study was to consider how the deep abdominal muscles responded to alterations in seated stability. The thickness of the right transverse abdominis (TrA) and internal oblique (IO) muscles were measured with ultrasound imaging in 30 healthy human subjects (mean age 27.7, years 22 females) in supine lying, relaxed sitting on a chair with both feet on the ground, relaxed sitting on a gym ball with both feet on the ground and sitting on a gym ball lifting the left foot off the floor. Measurements were taken at the end of both inspiration and expiration. The results showed that muscle thickness expressed as a percentage of the actual muscle thickness in supine lying did not differ between relaxed sitting on a chair and sitting on a gym ball for either muscle (P=0.012-0.054) where Bonferroni corrected P-value for significance=0.002. Raising the foot off the floor produced a significant increase in thickness for TrA and IO, when compared with the other seated postures (P<0.001). It was also found that both muscles were thicker at the end of expiration (P<0.001) which has also been established by other authors. These findings suggest that both deep abdominal muscles respond in the same way to postural changes. It also demonstrates that these muscles are automatically targeted by significantly decreasing the base of support, but in normal subjects sitting on a gym ball is not sufficient to increase their activity.

BMJ open sport & exercise medicine, 2016

People with chronic low back pain (CLBP) demonstrate greater postural instability compared with a... more People with chronic low back pain (CLBP) demonstrate greater postural instability compared with asymptomatic individuals. Rocker-sole shoes are inherently unstable and may serve as an effective balance training device. This study hypothesised that wearing rocker-sole shoes would result in long-term improvement in barefoot postural stability in people with CLBP. 20 participants with CLBP were randomised to wear rocker-sole or flat-sole shoes for a minimum of 2 hours each day. Participants were assessed barefoot and shod, over three 40 s trials, under 4 posture challenging standing conditions. The primary outcome was postural stability assessed by root mean squared error of centre of pressure (CoP) displacement (CoPRMSE AP) and mean CoP velocity (CoPVELAP), both in the anteroposterior direction, using force plates. Participants' were assessed without knowledge of group allocation at baseline, 6 weeks and 6 months (main outcome point). Analyses were by intention-to-treat. At 6 mont...

Archives of Physical Medicine and Rehabilitation, Nov 1, 2008

Endleman I, Critchley DJ. Transversus abdominis and obliquus internus activity during Pilates exe... more Endleman I, Critchley DJ. Transversus abdominis and obliquus internus activity during Pilates exercises: measurement with ultrasound scanning. Arch Phys Med Rehabil 2008;89:2205-12. Objective: To assess activity of transversus abdominis (TrA) and obliquus internus abdominis (OI) muscles during classical Pilates exercises performed correctly and incorrectly, and with or without equipment.

Rheumatology, Apr 1, 2014

and refined using Nominal Group Technique. Comparator groups confused with IIM were defined. Data... more and refined using Nominal Group Technique. Comparator groups confused with IIM were defined. Data collection: Within this retrospective case control study, clinical and laboratory data from IIM and comparator patients were collected from 47 rheumatology, dermatology, neurology and pediatrics clinics worldwide from 2008-2011. Data for external validation analysis were extracted from the UK juvenile myositis register. Analysis: Crude pair-wise associations among all variables measured and between each variable and clinician's diagnosis were assessed. Three approaches for derivation of classification criteria were explored: (i) Traditional: case defined by specified number of items from a set; (ii) Risk score: patient assigned a probability risk score by summing score-points associated with the variables (Probability model 1 and 2); (iii) Classification tree: case defined by a decision tree. A random forest algorithm explored the most important variables. Results obtained with each approach were utilized to improve others iteratively. Validation: Internal validation using bootstrap methods was performed. External validation using extracted data from an UK juvenile myositis register was performed. Results: Data from 973 IIM patients (74% adults; 26% children), representing subgroups of IIM (245 polymyositis, 239 dermatomyositis, 176 inclusion body myositis and 246 juvenile dermatomyositis cases) and 629 comparators (81% adults; 19% children) were obtained. The comparators include other myopathies and systemic rheumatic diseases. Two probability score models were developed: Model 1 comprised clinical variables on muscles, skin, and laboratory measures; Model 2 additionally comprised muscle biopsy variables. Model 1 performed nearly as well as Model 2 and both models performed as well as and often better than, the classification tree that was developed and published criteria. External validation using data on 332 juvenile myositis cases resulted in 100% sensitivity of the probability model. Conclusion: New classification criteria for IIM with readily clinically assessable measurements and symptoms have been developed. They generally show superior performance compared with existing criteria. Disclosure statement: C.A.P. has served as a consultant for UCB and Pfizer; and has received grants/research support from Arthritis Research UK. J.A.S. has served as a consultant for Savient, Takeda, Regeneron and Allergan; has received grants/research support from Takeda and Savient; and is an Omeract executive. All other authors have declared no conflicts of interest.

BMJ Open, 2016

Chronic low back pain (CLBP) is a common condition and source of significant suffering, disabilit... more Chronic low back pain (CLBP) is a common condition and source of significant suffering, disability and healthcare costs. Current physiotherapy treatment is moderately effective. Combining theory-based psychological methods with physiotherapy could improve outcomes for people with CLBP. The primary aim of this randomised controlled trial (RCT) is to evaluate the efficacy of Physiotherapy informed by Acceptance and Commitment Therapy (PACT) on functioning in patients with CLBP. The PACT trial is a two-armed, parallel-group, multicentre RCT to assess the efficacy of PACT in comparison with usual physiotherapy care (UC). 240 patients referred to physiotherapy with CLBP will be recruited from three National Health Service (NHS) hospitals trusts. Inclusion criteria are: age ≥18 years, CLBP ≥12-week duration, scoring ≥3 points on the Roland-Morris Disability Questionnaire (RMDQ) and adequate understanding of spoken and written English to participate. Patients will be randomised to PACT or UC (120 per arm stratified by centre) by an independent randomisation service and followed up at 3 and 12 months post randomisation. The sample size of 240 will provide adequate power to detect a standardised mean difference of 0.40 in the primary outcome (RMDQ; 5% significance, 80% power) assuming attrition of 20%. Analysis will be by intention to treat conducted by the trial statistician, blind to treatment group, following a prespecified analysis plan. Estimates of treatment effect at the follow-up assessments will use an intention-to-treat framework, implemented using a linear mixed-effects model. This trial has full ethical approval (14/SC/0277). It will be disseminated via peer-reviewed publications and conference presentations. The results will enable clinicians, patients and health service managers to make informed decisions regarding the efficacy of PACT for patients with CLBP. ISRCTN95392287; Pre-results.

Disability and rehabilitation, Jan 10, 2016

Purpose To translate and cross-culturally adapt the Back Beliefs Questionnaire (BBQ) into modern ... more Purpose To translate and cross-culturally adapt the Back Beliefs Questionnaire (BBQ) into modern standard Arabic and examine its validity, acceptability and reliability in Arabic-speaking patients with low back pain (LBP). Method The BBQ was forward, back-translated and reviewed by an expert committee. Seventeen bilingual patients completed Arabic and English BBQs. LBP patients (n = 199) completed the Arabic BBQ. Sixty-four repeated it a week later, and 151 completed the Arabic Fear-avoidance Beliefs Questionnaire (FABQ). Results The expert committee followed advice from the developers to maintain Arabic equivalence of "back trouble(s)". Patients found the questionnaire comprehensible and acceptable. Agreement between the English and Arabic versions of the BBQ was acceptable, ICC = 0.65 (0.25-0.86). Most item-by-item agreement ranged from fair to moderate (K = 0.12-0.54). Mean (SD) of BBQ, FABQ total, work and physical activity subscales were 25.31(6.13), 44.76(19.49), 21...

SPINE, 2016

Systematic review. To review the evidence regarding the mechanism of action of mobilizations. Spi... more Systematic review. To review the evidence regarding the mechanism of action of mobilizations. Spinal mobilizations-low velocity passive oscillatory movements-reduce spinal pain in some patient subgroups. Identifying patients likely to respond remains a challenge since mobilizations' mechanism(s) of action are unclear. Medline, Web of Science, Cinahl, Embase, and Scopus databases were searched for relevant studies. Reference lists of included studies were hand searched. Studies were included if the intervention was passive spinal mobilizations, participants were symptomatic, and outcomes evaluated possible mechanisms of action. Methodological quality was independently assessed by two assessors using a modified Cochrane Back Review Group tool. Twenty-four studies were included in the review. Four were classified high risk, 14 moderate risk, and four low risk of bias. Commonest methodological limitations were lack of participant blinding, adequate randomization and allocation concealment, and sample size calculation. Evidence suggests that spinal mobilizations cause neurophysiological effects resulting in hypoalgesia (local and/or distal to mobilization site), sympathoexcitation, and improved muscle function. Mobilizations have no effect on temperature pain threshold. Three of four studies reported reduction in spinal stiffness, heterogeneous in location and timing. There is limited evidence (one study in each case) to suggest that mobilizations produce increased nociceptive flexion reflex threshold, improved posture, decreased concentration of substance P in saliva, and improved sway index measured in cervical extension. Evidence does not support an effect on segmental vertebral movement. Two studies investigated correlations between hypoalgesia and mechanism: one found a correlation with sympathoexcitatory changes, whereas the other found no correlation with change in stiffness. These findings suggest involvement of an endogenous pain inhibition system mediated by the central nervous system, although this is yet to be investigated directly. There is limited evidence regarding other possible mechanisms. 3.

Rheumatology, Apr 1, 2014

them all. The relationship between process and experience (how young people feel about it) is not... more them all. The relationship between process and experience (how young people feel about it) is not clear-cut. Both process and experience vary, but not directly in parallel. Our data offer an explanation for this: that reported experience is informed by features of both the past and the present. Important factors seem to be: the young person's orientation to change; the correspondence between the actual and expected decision-making process; and how-at the time of interview-young people are finding treatment itself. Conclusion: Service type (paediatric, young adult, or adult) is a predictable determinant of process, but which might neverthelessfrom the point of view of equity-warrant further scrutiny and discussion. However, it is not the only thing that shapes process. Moreover it is evident that process alone does not determine young people's experience. Underpinning all the factors informing young people's experience is communication with and from health professionals-about why the decision should be made, what the process will involve (in particular when the decision point will come) and how, post-decision, they find treatment itself. Fine-tuning communication on these matters may help more young people to reflect positively on an inevitably complex decision. Disclosure statement: The authors have declared no conflicts of interest.

Spine, 2014

Cross-cultural translation, adaptation, and psychometric testing. To cross-culturally translate a... more Cross-cultural translation, adaptation, and psychometric testing. To cross-culturally translate and adapt the Roland-Morris Disability Questionnaire (RMDQ) into Modern Standard Arabic and examine its validity with Arabic-speaking patients with low back pain (LBP). The English RMDQ is valid, reliable, and commonly used to assess LBP disability in clinical practice and research. There is no valid and reliable version of the RMDQ in Modern Standard Arabic. The RMDQ was forward translated and back translated. An expert committee of musculoskeletal physiotherapists reviewed the translation. Eight patients with LBP evaluated item-by-item comprehensibility. Ten patients piloted the RMDQ for overall comprehensibility and acceptability. Seventeen bilingual patients tested the agreement of the Arabic and English RMDQs. Two-hundred one patients completed the RMDQ and the visual analogue scale. Sixty-four patients were followed-up for test-retest reliability. Translation of most items was uncontroversial. The expert committee found the Arabic RMDQ clinically and culturally appropriate. They reviewed item 11, addressing bending and kneeling, because this has a clinical significance and cultural/religious implication regarding prayer positions. All patients reported that it was easy to understand and complete. The Arabic RMDQ had high overall agreement with the English RMDQ for the global score (intraclass correlation coefficient [ICC] = 0.925; 0.811-0.972). Kappa statistics showed good item-by-item agreement (none ≤0.30). Mean (SD) RMDQ and visual analog scale scores of 201 patients were 10.53 (4.80) and 5.11 (2.28), respectively. The RMDQ had a low correlation against pain intensity (r = 0.259; P < 0.01). A Cronbach α of 0.729 showed high internal consistency. Test-retest reliability of the Arabic RMDQ was good (ICC = 0.900; 95% confidence interval, 0.753-0.951). Kappa statistics were high for 18 items and fair for 6. The Arabic version of the RMDQ has good comprehensibility and acceptability, high internal consistency and reliability, low correlation against pain intensity, and good agreement with the English RMDQ. We recommend its use with Arabic-speaking patients with LBP. 3.

Spine, 2013

Multicenter, assessor-blind, randomized, clinical trial. To compare the effectiveness of rocker s... more Multicenter, assessor-blind, randomized, clinical trial. To compare the effectiveness of rocker sole footwear to traditional flat sole footwear as part of the management for people with low back pain (LBP). During the past decade, persistent advertising has claimed that footwear constructed with a rocker sole will reduce LBP. However, there is no robust evidence to support these claims. One hundred fifteen people with chronic LBP were randomized to wear rocker sole shoes or flat sole shoes for a minimum of 2 hours each day while standing and walking. Primary outcome was the Roland Morris Disability Questionnaire (RMDQ). In addition, participants attended an exercise and education program once a week for 4 weeks and wore their assigned shoes during these sessions. Participants were assessed without their knowledge of group allocation prerandomization, and at 6 weeks, 6 months, and 1 year (main outcome point). Analysis was by intention-to-treat method. At 12 months, data from 44 of 58 (77.2%) of the rocker sole group and 49 of 57 (84.5%) of the flat sole group were available for analysis. In the rocker sole group, mean reduction in RMDQ was -3.1 (95% CI [confidence interval], -4.5 to -1.6), and in the flat sole group, it was -4.4 (95% CI, -5.8 to -3.1) (a greater negative value represents a greater reduction in disability). At 6 months, more people wearing flat shoes compared with those wearing rocker shoes demonstrated a minimal clinically important improvement in disability (53.2% and 31.1%, respectively; P = 0.03). Between-group differences were not significant for RMDQ or any secondary outcomes (e.g., pain) at any time. People reporting pain when standing and walking at baseline (n = 59) reported a greater reduction in RMDQ at 12 months in the flat sole group (-4.4 [95% CI, -6.0 to -2.8], n = 29) than the rocker sole group (-2.0 [95% CI, -3.6 to -0.4], n = 30) (P < 0.05). Rocker sole shoes seem to be no more beneficial than flat sole shoes in affecting disability and pain outcomes in people with chronic LBP. Flat shoes are more beneficial for LBP aggravated by standing or walking. N/A.

Spine, 2007

Pragmatic, randomized, assessor blinded, clinical trial with economic analysis. To compare the ef... more Pragmatic, randomized, assessor blinded, clinical trial with economic analysis. To compare the effectiveness and cost-effectiveness of three kinds of physiotherapy commonly used to reduce disability in chronic low back pain. Physiotherapy reduces disability in chronic back pain, but there are several forms of physiotherapy and it is unclear which is most effective or cost effective. A total of 212 patients referred to physiotherapy with chronic low back pain were randomized to receive usual outpatient physiotherapy, spinal stabilization classes, or physiotherapist-led pain management classes. Primary outcome was Roland Disability Questionnaire score 18 months from baseline; secondary measures were pain, health-related quality of life, and time off work. Healthcare costs associated with low back pain and quality-adjusted life years (QALYs) were also measured. RESULTS.: A total of 71 participants were assigned to usual outpatient physiotherapy, 72 to spinal stabilization, and 69 to physiotherapist-led pain management. A total of 160 (75%) provided follow-up data at 18 months, showing similar improvements with all interventions: mean (95% confidence intervals) Roland Disability Questionnaire score improved from 11.1 (9.6-12.6) to 6.9 (5.3-8.4) with usual outpatient physiotherapy, 12.8 (11.4-14.2) to 6.8 (4.9-8.6) with spinal stabilization, and 11.5 (9.8-13.1) to 6.5 (4.5-8.6) following pain management classes. Pain, quality of life, and time off work also improved within all groups with no between-group differences. Mean (SD) healthcare costs and QALY gain were pound474 (840) and 0.99 (0.27) for individual physiotherapy, pound379 (1040) and 0.90 (0.37) for spinal stabilization, and pound165 (202) and 1.00 (0.28) for pain management. For chronic low back pain, all three physiotherapy regimens improved disability and other relevant health outcomes, regardless of their content. Physiotherapist-led pain management classes offer a cost-effective alternative to usual outpatient physiotherapy and are associated with less healthcare use. A more widespread adoption of physiotherapist-led pain management could result in considerable cost savings for healthcare providers.

Manual Therapy, 2006

The purpose of this study was to consider how the deep abdominal muscles responded to alterations... more The purpose of this study was to consider how the deep abdominal muscles responded to alterations in seated stability. The thickness of the right transverse abdominis (TrA) and internal oblique (IO) muscles were measured with ultrasound imaging in 30 healthy human subjects (mean age 27.7, years 22 females) in supine lying, relaxed sitting on a chair with both feet on the ground, relaxed sitting on a gym ball with both feet on the ground and sitting on a gym ball lifting the left foot off the floor. Measurements were taken at the end of both inspiration and expiration. The results showed that muscle thickness expressed as a percentage of the actual muscle thickness in supine lying did not differ between relaxed sitting on a chair and sitting on a gym ball for either muscle (P=0.012-0.054) where Bonferroni corrected P-value for significance=0.002. Raising the foot off the floor produced a significant increase in thickness for TrA and IO, when compared with the other seated postures (P<0.001). It was also found that both muscles were thicker at the end of expiration (P<0.001) which has also been established by other authors. These findings suggest that both deep abdominal muscles respond in the same way to postural changes. It also demonstrates that these muscles are automatically targeted by significantly decreasing the base of support, but in normal subjects sitting on a gym ball is not sufficient to increase their activity.