Development and assessment of a verbal response scale for the Patient-Specific Functional Scale (PSFS) in a low-literacy, non-western population.

PURPOSE: The Patient-Specific Functional Scale (PSFS) is a routinely used measure of physical function with a 0-10 response scale. We aimed to develop verbal response options for the PSFS, pre-test it for use in a multilingual, low-literacy country- Nepal, and compare preference and error rates between numeric and verbal scale. We hypothesized that a verbal scale would be preferred by respondents and yield fewer errors. METHOD: We interviewed 42 individuals with musculoskeletal, neurological, and cardiopulmonary conditions to understand how people describe varying levels of physical ability. Transcripts were thematically analyzed, and through consensus, we developed two sets of verbal responses for the PSFS. Next, we pre-tested the scales on an additional 119 respondents following which participants were asked to specify their preferred scale. Error rates were analyzed retrospectively using pre-specified criteria. RESULTS: Participants described their ability in terms of the quality (95%) and the quantity of task performance (88%). Although the verbal scales were preferred over the numeric scale (50% versus 12%), there was no significant difference in error rates between numeric (34%) and verbal scales (32% and 36%). Higher error rates were associated with greater age, fewer years of education, and inexperience with numeric scales. CONCLUSION: Despite a higher preference for verbal scale, 1 out of 3 patients made errors in using the PSFS, even with an interview format. The error rates were higher among participants with low literacy. The findings raise questions about the utility of PROMs in countries with low literacy rates.

GT3X+ accelerometer placement affects the reliability of step-counts measured during running and pedal-revolution counts measured during bicycling.

UNLABELLED: Accelerometers provide a measure of step-count. Reliability and validity of step-count and pedal-revolution count measurements by the GT3X+ accelerometer, placed at different anatomical locations, is absent in the literature. The purpose of this study was to investigate the reliability and validity of step and pedal-revolution counts produced by the GT3X+ placed at different anatomical locations during running and bicycling. Twenty-two healthy adults (14 men and 8 women) completed running and bicycling activity bouts (5 minutes each) while wearing 6 accelerometers: 2 each at the waist, thigh and shank. Accelerometer and video data were collected during activity. Excellent reliability and validity were found for measurements taken from accelerometers mounted at the waist and shank during running (Reliability: intraclass correlation (ICC) ≥ 0.99; standard error of measurement (SEM) ≤1.0 steps; VALIDITY: Pearson ≥ 0.99) and at the thigh and shank during bicycling (Reliability: ICC ≥ 0.99; SEM ≤1.0 revolutions; VALIDITY: Pearson ≥ 0.99). Excellent reliability was found between measurements taken at the waist and shank during running (ICC ≥ 0.98; SEM ≤1.6 steps) and between measurements taken at the thigh and shank during bicycling (ICC ≥ 0.99; SEM ≤1.0 revolutions). These data suggest that the GT3X+ can be used for measuring step-count during running and pedal-revolution count during bicycling. Only shank placement is recommended for both activities.

Fat Infiltration in the Leg is Associated with Bone Geometry and Physical Function in Healthy Older Women.

The objective of this study was to estimate the associations between muscular fat infiltration, tibia bone mineral quantity and distribution, and physical function in healthy older women. Thirty-five women (aged 60-75 years, mean 70 years) were recruited from the community. Percent intramuscular fat (%IntraMF) within the right leg tibialis anterior, soleus, and gastrocnemius muscles and total intermuscular fat (IMF) were segmented from magnetic resonance imaging scans at the mid-calf. Intramyocellular lipid (IMCL) content in the right tibialis anterior was measured with proton magnetic resonance spectroscopy. Right tibia bone content, area, and strength were measured at the 4, 14, and 66% sites using peripheral quantitative computed tomography. Physical function was assessed by gait speed on the 20 m walking test. After adjusting for age, body size, and activity level, %IntraMF had a negative association with bone content and area at all tibia sites (r = -0.31 to -0.03). Conversely, greater IMF was associated with increased bone content and area (r = 0.04-0.32). Correlation coefficients for the association between IMCL and bone were negative (r = -0.44 to -0.03). All measures of fat infiltration had a negative association with observed physical function (r = -0.42 to -0.04). Our findings suggest that muscular fat infiltration in the leg of healthy postmenopausal women has a compartment-specific relationship with bone status and physical function. Minimizing fat accumulation within and between muscle compartments may prevent bone fragility and functional decline in women.

Do Knee Moments Normalized to Measures of Knee Cartilage Area Better Classify the Severity of Knee Osteoarthritis?

Investigations of joint loading in knee osteoarthritis (OA) typically normalize the knee adduction moment to global measures of body size (eg, body mass, height) to allow comparison between individuals. However, such measurements may not reflect knee size. This study used a morphometric measurement of the cartilage surface area on the medial tibial plateau, which better represents medial knee size. This study aimed to determine whether normalizing the peak knee adduction moment and knee adduction moment impulse during gait to the medial tibial bone-cartilage interface could classify radiographic knee OA severity more accurately than traditional normalization techniques. Individuals with mild (N = 22) and severe (N = 17) radiographic knee OA participated. The medial tibial bone-cartilage interface was quantified from magnetic resonance imaging scans. Gait analysis was performed, and the peak knee adduction moment and knee adduction moment impulse were calculated in nonnormalized units and normalized to body mass, body weight × height, and the medial tibial bone-cartilage interface. Receiver operating characteristic curves compared the ability of each knee adduction moment normalization technique to classify participants according to radiographic disease severity. No normalization technique was superior at distinguishing between OA severities. Knee adduction moments normalized to medial knee size were not more sensitive to OA severity.

Progressing toward, and recovering from, knee replacement surgery: a five-year cohort study.

OBJECTIVE: To determine the trajectories of preoperative worsening and postoperative recovery for both the index knee and the contralateral knee of patients undergoing knee replacement surgery. METHODS: Of the 4,796 subjects in the Osteoarthritis Initiative cohort study database, we examined 5-year data from 177 patients who underwent isolated unilateral knee replacement surgery and no other joint replacement surgery. Patient-reported outcomes captured domains defined by the International Classification of Functioning, Disability, and Health. Domains of knee structure and function, activity limitation, and participation restriction were examined using growth-curve modeling over 5-year periods prior to and following surgery. RESULTS: Preoperative worsening of the index knee was substantial in all domains of knee impairment, activity limitation, and societal participation. Pain intensity worsened only slightly from 5 years to 2.5 years prior to surgery, but worsened by ∼2 points (0-10-point scale) during the 2.5 years prior to surgery. Trajectories of improvement following surgery varied depending on the outcome measure. The contralateral knee also changed over time, such that by ∼2 years following surgery, pain was worse and by 3 years, activity limitation was worse in the contralateral knee as compared to the index knee. CONCLUSION: Patients who elect to undergo knee replacement surgery demonstrate perioperative trajectories of change that influence most health domains for both the index knee and the contralateral knee. After a period of no change, escalation of pain and worsening functioning in the index knee begins ∼2.5 years prior to surgery, which may be a key trigger for surgery.

Difference in Physiotherapy Students' Training and Objective Structured Clinical Exam Performance Before and During COVID-19.

Purpose: The Objective Structured Clinical Examination (OSCE) and station examinations, in general, have been widely utilized in health professional programmes to evaluate students' clinical performance prior to advancing to a clinical placement. The COVID-19 pandemic impacted student preparation and implementation of our programme's OSCEs. The impact on changes in student OSCE performance due COVID-19 has not been well studied. This non-concurrent cohort study evaluated the difference before and during COVID-19 pandemic on Year 1 physiotherapy students' performances on an in-person OSCE by estimating the mean difference in cohort OSCE scores and safety occurrences. Methods: Two cohorts of MSc (PT) students were compared: Cohort A (not impacted by COVID-19) and Cohort B (impacted by COVID-19). Cohort scores were summarized as means and 95% CIs. Results: Overall OSCE scores for Cohort A and B were 77.9 and 81.9, respectively (d¯ = 4.0, 95% CI: 2.1, 5.8). Cohort B students were approximately 4 times more likely to demonstrate safety occurrences. Conclusion: The impact of COVID-19 did not adversely affect total OSCE scores; however, it did increase safety infractions.

Objectif: en général, les programmes pour les professionnels de la santé font largement appel à l'examen clinique objectif structuré (ECOS) et aux stations d'examen pour évaluer la performance clinique des étudiants avant leur passage au stage clinique. La pandémie de COVID-19 a nui à la préparation des étudiants et à la mise en œuvre des ECOS du programme de physiothérapie. Les effets sur les changements à la performance des étudiants à l'ECOS découlant de la COVID-19 n'ont pas été bien étudiés. La présente étude de cohorte non concomitante a permis d'évaluer la différence entre la performance des étudiants en première année de physiothérapie à un ECOS en personne avant et pendant la pandémie de COVID-19, d'après la différence moyenne des scores d'ECOS et des occurrences d'infractions aux règles de sécurité au sein des deux cohortes. Méthodologie: deux cohortes d'étudiants à la maîtrise en physiothérapie ont été comparées : la cohorte A (non touchée par la COVID-19) et B (touchée par la COVID-19). Les scores des cohortes ont été résumés sous forme de moyennes et d'IC à 95%. Résultats: les scores globaux de l'ECOS pour la cohorte A et la cohorte B s'élevaient à 77,9 et à 81,9, respectivement (d¯ = 4,0, IC à 95 % : 2,1, 5,8). Les étudiants de la cohorte B étaient environ quatre fois plus susceptibles de démontrer des occurrences d'infraction aux règles de sécurité. Conclusion: la COVID-19 n'a pas nui aux scores totaux de l'ECOS, mais les infractions aux règles de sécurité se sont accrues.

Interactions of cumulative load with biomarkers of cartilage turnover predict knee cartilage change over 2 years: data from the osteoarthritis initiative.

The purpose was to investigate relationships of cumulative load and cartilage turnover biomarkers with 2-year changes in cartilage in knee osteoarthritis. From participants with Kellgren-Lawrence (KL) grades of 1 to 3, cartilage thickness and transverse relaxation time (T2) were computed from 24-month (baseline) and 48-month magnetic resonance images. Cumulative load was the interaction term of the Physical Activity Scale for the Elderly (PASE) and body mass index (BMI). Serum cartilage oligomeric matrix protein (COMP) and the nitrated form of type II collagen (Coll2-1 NO2) were collected at baseline. Multiple regressions (adjusted for baseline age, KL grade, cartilage measures, pain, comorbidity) evaluated the relationships of cumulative load and biomarkers with 2-year changes. In 406 participants (63.7 (8.7) years), interactions of biomarkers with cumulative load weakly predicted 2-year cartilage changes: (i) COMP × cumulative load explained medial tibia thickness change (R2 increased 0.062 to 0.087, p < 0.001); (ii) Coll2-1 NO2 × cumulative load explained central medial femoral T2 change (R2 increased 0.177 to 0.210, p < 0.001); and (iii) Coll2-1 NO2 × cumulative load explained lateral tibia T2 change (R2 increased 0.166 to 0.188, p < 0.001). Moderate COMP or Coll2-1 NO2 at baseline appeared protective. High COMP or Coll2-1 NO2, particularly with high BMI and low PASE, associated with worsening cartilage. Moderate serum concentrations of cartilage turnover biomarkers, at high and low physical activity, associated with maintained cartilage outcomes over 2 years. In conclusion, high concentrations of cartilage turnover biomarkers, particularly with high BMI and low physical activity, associated with knee cartilage thinning and increasing T2 over 2 years. Key Points • Higher quality cartilage may be better able to tolerate a larger cumulative load than poor quality cartilage. • Among participants enrolled in the Osteoarthritis Initiative Biomarkers Consortium Project, a representation of cumulative load exposure and its interaction with cartilage turnover biomarkers were weakly related with 2-year change in knee cartilage. • These findings suggest that cartilage turnover is a factor that modifies the relationship between loading exposure and cartilage loss in knee OA.

Predictors of Success in a Graduate, Entry-Level Professional Program: From Admissions to Graduation.

INTRODUCTION: Admission to health professional programs (HPPs) in Canada is competitive. The purpose of this study is to evaluate how factors identifiable by the admissions package may predict incidences of academic concerns in one physiotherapy program in Canada. REVIEW OF LITERATURE: Previous literature has identified many concepts that contribute to "academic success." Some HPPs have investigated if admissions criteria can predict students' academic performance. However, this has not been reported in physiotherapy programs in Canada. SUBJECTS: Study data included candidates' admissions' metrics and physiotherapy students' program data for 4 graduating cohorts, who were admitted from 2016 to 2019 inclusive (N = 256). METHODS: A retrospective, nonconcurrent cohort study was used to estimate the relationship between applicant's admissions data and students' program data pertaining to academic success. Data were summarized as frequencies for categorical variables and means for continuous variables. We calculated odds ratios (ORs) and probabilities of an academic or professional concern for standard scores. Significance was set at P < .05. RESULTS: Cohorts participating in the multiple mini-interview (MMI) had an academic concern incidence of 14/131. The virtual MMI (VMMI) cohort had an incidence of 7/125. Students with higher MMI scores were less likely to have an academic concern (OR = 0.52 [95% CI: 0.30-0.89, P = .017]). Grade point average was not significantly associated with an academic concern when combined with either MMI or VMMI (Ps > 0.05). Admissions round offer was also significantly associated with an academic concern (OR = 2.48 [95% CI: 1.00-6.12, P = .049]), with those beyond the initial round of offers having increased risk of concerns. DISCUSSION AND CONCLUSION: Results of the study reflect the generally low event rates for incidences of academic concerns and the relative homogeneity and range restriction of independent variables across the 4 cohorts of students. HPP's reflection on current admissions processes and ability to identify opportunities for change in admission processes helps ensure that programs are selecting candidates who are likely to succeed.

Unilateral vs bilateral symptomatic knee osteoarthritis: associations between pain intensity and function.

OBJECTIVE: The objective of this study was to determine if associations between pain distribution (unilateral vs bilateral) and measures of function (self-report vs performance-based) were influenced by knee pain intensity of the painful knee(s) in persons with moderate to severe symptomatic knee OA. METHODS: Data from persons in the Osteoarthritis Initiative (OAI) dataset (n = 852) with symptomatic knee OA were studied. Key dependent variables were the WOMAC physical function, Knee Injury and Osteoarthritis Outcome Score (KOOS) quality of life, the repeated chair stand test and the 20-m walk test. In addition to covariates, the independent variables were the presence of unilateral or bilateral OA involvement (either Kellgren and Lawrence grade 3 or 4 or a grade <3) and pain category (mild, moderate or severe). RESULTS: WOMAC physical function scores consistently showed the strongest association with pain intensity for persons with unilateral vs bilateral knee pain. For example, in persons with unilateral severe knee pain, WOMAC scores averaged 19.9 (S.D. = 12.0) points while persons with bilateral knee pain with at least one knee rated as severe had WOMAC scores ranging from 25.3 to 28.9, depending on pain severity of the contralateral knee. These differences were statistically significant (P < 0.001) as was the test for trend (P = 0.001). Self-report measures generally showed larger effect sizes than performance-based measures. CONCLUSION: Knee pain intensity influences self-report and performance-based tests differently depending on whether knee pain is unilateral or bilateral. WOMAC scores are most strongly associated with pain intensity in persons with unilateral vs bilateral pain while walking tests are least influenced by pain intensity.

Does peak expiratory flow moderate trajectories of cognitive function among individuals with lung diseases? A longitudinal analysis of the National Health and Aging Trends Study.

INTRODUCTION: Impaired cognitive function can co-exist in chronic respiratory diseases. However, it is not clear if peak expiratory flow (PEF) impacts changes in cognitive function. Our objective was to explore whether peak expiratory flow moderates trajectories of memory, visuospatial abilities, and executive function in individuals with chronic respiratory diseases. METHODS: This was an analysis of individuals with lung diseases from the National Health and Aging Trends Study. Multivariable-adjusted generalized linear mixed models were used to estimate trajectories of immediate and delayed recall, and clock drawing over a 10-year follow-up. The interaction between PEF and time were plotted using sex-specific values for peak expiratory flow at 10th, 50th and 90th percentiles. RESULTS: In females, interactions of time-by-PEF were found for both immediate (n = 489, t = 2.73, p<0.01) and delayed recall (n = 489, t = 3.38, p<0.01). Females in the 10th vs. 90th percentile of PEF declined in immediate recall at 0.14 vs. 0.065 words/year, and 0.17 vs. 0.032 words/year for delayed recall. Among males, recall declined linearly over 10 years (immediate recall: n = 296, t = -3.08, p < 0.01; delayed recall: n = 292, t = -2.46, p = 0.02), with no interaction with PEF. There were no time-by-PEF interactions nor declines over time in clock drawing scores in both sexes (females: n = 484, t = 0.25, p = 0.81; males: n = 291, t = -0.61, p = 0.55). CONCLUSION: Females with the lowest PEF values experienced the greatest rates of decline in immediate and delayed recall over 10 years of follow-up, whereas males experienced similar declines in memory outcomes across all levels of PEF. Clock drawing scores remained stable over 10 years in both sexes.

Intrarater reliability of dual-energy X-ray absorptiometry-based measures of vertebral height in postmenopausal women.

The primary purpose was to estimate intrarater reliability of vertebral body height (VH) measures in postmenopausal women based on duplicate analyses of vertebral fracture assessment (VFA) images. The secondary purpose was to determine the consistency in classification of vertebral deformity on duplicate analyses. Thirty-two VFA were randomly selected from a database of 464 scans acquired in postmenopausal women using dual-energy X-ray absorptiometry (Discovery A; Hologic Inc., Waltham, MA). Visible endplates were marked on each image on 2 occasions (4 wk apart) by a single rater; the semiautomated software derived measures of anterior, middle, and posterior VH and classified severity of vertebral deformity. Intrarater reliability was assessed using the intraclass correlation coefficient (with 95% confidence interval [CI]) when ≥ 22 VFA could be analyzed. Reliability of grading deformity of 267 vertebrae was assessed using Cohen's unweighted kappa (with 95% CI). Reliability of anterior, middle, and posterior height measures from T8 to L4 was 0.85 and greater except for T8 anterior VH and T9 posterior VH (0.76 [0.43, 0.90] and 0.62 [0.15, 0.83], respectively). Chance-corrected agreement for 4 grades of vertebral deformity was 0.48 (0.30, 0.66) and for 2 categories (normal/mild and moderate/severe) was 0.70 (50, 0.90). Intrarater reliability was acceptable for VH measures from T10 to L4. Reliability in grading severity of deformity was improved by classifying as <25% deformity (nonfracture) and as >25% deformity (fracture).

Longitudinal changes in the lower extremity functional scale after anterior cruciate ligament reconstructive surgery.

OBJECTIVE: To describe the pattern of change in lower extremity physical function status as measured by the Lower Extremity Functional Scale (LEFS) during the first 16 weeks after anterior cruciate ligament (ACL) reconstructive surgery and illustrate how this information can be applied in clinical practice to assist with goal setting and the evaluation of patient outcomes. The secondary objective is to estimate the test-retest reliability of the LEFS in this population. DESIGN: Prospective cohort, observational. SETTING: Physiotherapy private practice. PATIENTS: Forty-seven participants underwent ACL reconstructive surgery and were initially recruited. Two participants were excluded from the analysis, resulting in 45 participants (28 men, mean age 29.4 years; 17 women, mean age 29.0 years). INTERVENTIONS: Participants underwent a rehabilitation protocol. MAIN OUTCOME MEASURES: Participants completed the LEFS at each visit from their initial physiotherapy session to 16 weeks postsurgery. A nonlinear model of change was developed, which related LEFS scores to weeks postsurgery. Test-retest reliability was examined between the seventh and ninth weeks using intraclass correlation coefficients (ICC2,1) and standard error of measurement (SEM). RESULTS: The nonlinear model demonstrated rapid improvements in LEFS scores within the first 7 to 8 weeks with a gradual tapering of this improvement. At 16 weeks, the predicted LEFS score was 63 out of a maximum score of 80. The LEFS demonstrated excellent test-retest reliability in this population (ICC2,1 = 0.90, SEM = 3.7). CONCLUSIONS: This study provides a description of postsurgical change in functional status for patients after ACL reconstructive surgery that can assist clinicians in developing clinical goals. CLINICAL RELEVANCE: A rapid improvement in lower extremity physical function is demonstrated in the first 7 to 8 weeks after ACL reconstructive surgery with a tapering of this improvement after 8 weeks.

Sex Differences in Functional Capacity in Older Adults With Stroke: An Analysis of Data From the National Health and Aging Trends Study.

OBJECTIVE: Women experience greater disability following stroke, but biological sex differences in both overall and specific domains of functional capacity are not well understood. The primary objective of this study was to examine sex differences in overall functional capacity (Short Physical Performance Battery [SPPB] score) cross-sectionally and longitudinally over a 3-year follow-up period. The secondary objective was to determine whether sex differences exist in specific domains of functional capacity of walking speed and lower extremity functional strength. METHODS: This study was a secondary analysis of data of individuals with stroke from the National Health and Aging Trends Study. For the cross-sectional analyses, general linear models were used to examine differences between 293 men and 427 women in SPPB, walking speed, and the 5-Times Sit-to-Stand Test (5XSST). For the longitudinal analysis, survey-weighted, multivariable-adjusted generalized linear mixed models were used to compare 3-year trajectories in SPPB scores between the sexes (87 men, 153 women). RESULTS: Women had lower SPPB scores at baseline (difference = 0.9, linearized SE = 0.3) and over 3 years. SPPB scores declined similarly between men and women. Women had lower walking speed (difference = 0.08 m/s, SE = 0.02) as compared with men, but men and women had similar 5XSST scores (difference = 0.6 seconds, SE = 0.5). CONCLUSION: Older women with stroke have clinically meaningfully lower overall functional capacity as compared with older men but decline at a similar rate over time. Walking speed was lower in older women with stroke, but similar between sexes in 5XSST. IMPACT: Women with stroke have poorer functional capacity compared with men, which reinforces the importance of targeted stroke rehabilitation strategies to address these sex-specific disparities. LAY SUMMARY: Women with stroke have poorer outcomes in terms of their ability to move around the community when compared with men. However, both men and women with stroke have similar physical functioning over time.

Using outcome measure results to facilitate clinical decisions the first year after total hip arthroplasty.

STUDY DESIGN: Variable-occasion, repeated-measures design. OBJECTIVES: To model change in lower extremity functional status of patients 1 year after total hip arthroplasty (THA), using the Lower Extremity Functional Scale (LEFS) and the 6-minute walk test (6MWT), and, secondarily, to provide clinicians with useful data to guide practice. BACKGROUND: Given the prevalence of THA and current resource pressures, standardized outcome measures play an important role in providing physical therapists with objective knowledge about postoperative recovery and prognosis. METHODS: Seventy-five patients, with a mean age of 61 years and a diagnosis of hip osteoarthritis, consented to participate in the study. Assessments were conducted preoperatively and at multiple time points for up to 65 weeks postoperatively. Recovery was modeled using a nonlinear robust regression analysis for clustered data. The predictive ability of age, body mass index, and preoperative score was explored. RESULTS: Gender-based recovery curves were generated to depict the rate and amount of change in LEFS scores and 6MWT distances over the first year. Preoperative baseline 6MWT distance was the only covariate predictive of postarthroplasty 6MWT distances for both males and females. None of the covariates examined were significantly associated with postarthroplasty LEFS scores. CONCLUSION: Although there were variations in the recovery curves by measure, general patterns were noted. There was a rapid increase in both self-reported and physical performance measure scores for 12 to 15 weeks. Thereafter, we observed a slowing of recovery, with a plateau at 30 to 35 weeks for the 6MWT and later for the LEFS. These data can be used to make evidence-based decisions regarding prognosis and to guide the setting of measurable treatment goals. LEVEL OF EVIDENCE: Prognosis, level 1b.

Effect of fear-avoidance beliefs of physical activities on a model that predicts risk-adjusted functional status outcomes in patients treated for a lumbar spine dysfunction.

STUDY DESIGN: Retrospective analysis of a prospective, longitudinal cohort study of 30 858 patients being treated for a lumbar spine dysfunction in outpatient physical therapy. OBJECTIVES: To determine effect of adding a single-item screening variable classifying patients with elevated versus not-elevated scores of fear-avoidance beliefs of physical activities at intake, on a model predicting risk-adjusted functional status (FS) outcomes. BACKGROUND: Outcomes must be risk-adjusted before making meaningful interpretations. Elevated fear-avoidance beliefs scores have been predictive of poor outcomes. But the importance of elevated fear-avoidance scores in a multivariable model predicting FS outcomes needs further study. METHODS: Using retrospective analyses, predictive ability (R2) of multivariable linear regression models of discharge FS with and without classification by elevated versus not-elevated fear-avoidance scores were compared, while controlling for intake FS, age, symptom acuity, surgical history, gender, number of comorbidities, and payer. Percent variance controlled and beta coefficients (95% confidence intervals) of each variable in both models were compared. A split-half design was used for model cross-validation. Predictive ratios (predicted FS, divided by actual discharge FS) were assessed. RESULTS: Adding fear-avoidance beliefs classification to the discharge FS model improved (P<.001) model predictive ability but only slightly (R2 without, and with, fear-avoidance classification, 0.2997 and 0.3010, respectively). Variables impacted models similarly (95% confidence intervals not different). Fear-avoidance classification added 0.2% data variance control to the existing model. Cross-validation was supported. Predictive ratios were 1.09 and 1.10, without and with fear-avoidance, respectively. CONCLUSION: Although screening for elevated fear-avoidance beliefs of physical activities significantly improves the FS outcomes predictive model, the amount of additional meaningful interpretation of FS outcomes was minimal. Exploration of other clinically relevant variables designed to improve outcomes prediction is warranted. LEVEL OF EVIDENCE: Prognosis, level 2c.

Muscle strength gains after strengthening exercise explained by reductions in serum inflammation in women with knee osteoarthritis.

Background Individuals with knee osteoarthritis have elevated circulating inflammatory markers and altered cartilage properties but it is unclear if these features adapt to exercise. We aimed to determine (1) whether inflammatory markers, cartilage transverse relaxation time and thickness mediate the effect of body mass index (BMI) on quadriceps strength at baseline; and (2) whether these changes explain variance in quadriceps strength improvements after 12 weeks of exercise in women with knee osteoarthritis. Methods This secondary analysis (17 women with clinical knee osteoarthritis) of a randomized control trial compared supervised group interventions, 3 times/week for 12 weeks (36 sessions): (a) weight-bearing progressive resistive quadriceps exercise or (b) attention control. (1) From baseline, separate linear regressions were conducted with strength (Nm/kg) as the dependent, BMI as the predictor, and c-reactive protein, tumor necrosis factor, interleukin-6, cartilage transverse relaxation time or thickness as potential mediators. (2) Multiple linear regression analyses were completed with 12-week strength change (post-pre) as the dependent, change in serum inflammatory markers and cartilage measurements as predictors, and age, BMI and adherence as covariates. Findings (1) At baseline, there was no mediation. (2) A decrease in each of interleukin-6 (ß = -0.104 (95% confidence intervals: -0.172, -0.036), R2 = 0.51, P < 0.007) and tumor necrosis factor (ß = -0.024 (-0.038, -0.009), R2 = 0.54, P < 0.005) was associated with strength gains. Interpretation At baseline, inflammatory markers and cartilage measurements do not act as mediators of BMI on quadriceps strength. After 12 weeks of exercise, reduced interleukin-6 and tumor necrosis factor were associated with increased quadriceps strength in women with knee osteoarthritis.

Inter-rater agreement and reliability of the COSMIN (COnsensus-based Standards for the selection of health status Measurement Instruments) checklist.

BACKGROUND: The COSMIN checklist is a tool for evaluating the methodological quality of studies on measurement properties of health-related patient-reported outcomes. The aim of this study is to determine the inter-rater agreement and reliability of each item score of the COSMIN checklist (n = 114). METHODS: 75 articles evaluating measurement properties were randomly selected from the bibliographic database compiled by the Patient-Reported Outcome Measurement Group, Oxford, UK. Raters were asked to assess the methodological quality of three articles, using the COSMIN checklist. In a one-way design, percentage agreement and intraclass kappa coefficients or quadratic-weighted kappa coefficients were calculated for each item. RESULTS: 88 raters participated. Of the 75 selected articles, 26 articles were rated by four to six participants, and 49 by two or three participants. Overall, percentage agreement was appropriate (68% was above 80% agreement), and the kappa coefficients for the COSMIN items were low (61% was below 0.40, 6% was above 0.75). Reasons for low inter-rater agreement were need for subjective judgement, and accustom to different standards, terminology and definitions. CONCLUSIONS: Results indicated that raters often choose the same response option, but that it is difficult on item level to distinguish between articles. When using the COSMIN checklist in a systematic review, we recommend getting some training and experience, completing it by two independent raters, and reaching consensus on one final rating. Instructions for using the checklist are improved.

The COSMIN checklist for evaluating the methodological quality of studies on measurement properties: a clarification of its content.

BACKGROUND: The COSMIN checklist (COnsensus-based Standards for the selection of health status Measurement INstruments) was developed in an international Delphi study to evaluate the methodological quality of studies on measurement properties of health-related patient reported outcomes (HR-PROs). In this paper, we explain our choices for the design requirements and preferred statistical methods for which no evidence is available in the literature or on which the Delphi panel members had substantial discussion. METHODS: The issues described in this paper are a reflection of the Delphi process in which 43 panel members participated. RESULTS: The topics discussed are internal consistency (relevance for reflective and formative models, and distinction with unidimensionality), content validity (judging relevance and comprehensiveness), hypotheses testing as an aspect of construct validity (specificity of hypotheses), criterion validity (relevance for PROs), and responsiveness (concept and relation to validity, and (in) appropriate measures). CONCLUSIONS: We expect that this paper will contribute to a better understanding of the rationale behind the items, thereby enhancing the acceptance and use of the COSMIN checklist.

The COSMIN checklist for assessing the methodological quality of studies on measurement properties of health status measurement instruments: an international Delphi study.

BACKGROUND: Aim of the COSMIN study (COnsensus-based Standards for the selection of health status Measurement INstruments) was to develop a consensus-based checklist to evaluate the methodological quality of studies on measurement properties. We present the COSMIN checklist and the agreement of the panel on the items of the checklist. METHODS: A four-round Delphi study was performed with international experts (psychologists, epidemiologists, statisticians and clinicians). Of the 91 invited experts, 57 agreed to participate (63%). Panel members were asked to rate their (dis)agreement with each proposal on a five-point scale. Consensus was considered to be reached when at least 67% of the panel members indicated 'agree' or 'strongly agree'. RESULTS: Consensus was reached on the inclusion of the following measurement properties: internal consistency, reliability, measurement error, content validity (including face validity), construct validity (including structural validity, hypotheses testing and cross-cultural validity), criterion validity, responsiveness, and interpretability. The latter was not considered a measurement property. The panel also reached consensus on how these properties should be assessed. CONCLUSIONS: The resulting COSMIN checklist could be useful when selecting a measurement instrument, peer-reviewing a manuscript, designing or reporting a study on measurement properties, or for educational purposes.

Using hierarchical linear modeling to explore predictors of pain after total hip and knee arthroplasty as a consequence of osteoarthritis.

Hierarchical linear modeling was used to establish differences in, and the average pattern of, recovery of the pain subscale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and 2 composite performance-specific measures of pain as well as to determine if significant individual variations exist in the growth curves for each measure. Predictors of postoperative pain were also of interest. One hundred forty-seven patients undergoing unilateral primary hip or knee arthroplasty completed 4 performance measures-self-paced 40-m walk, timed up and go, stair test, and 6-minute walk-and the WOMAC prearthroplasty and at multiple points in time between 2 and 27 weeks postarthroplasty. Although patients reported different levels of postoperative pain initially, similar recovery patterns were noted. Predictive variables were found to be site of joint arthroplasty and WOMAC prearthroplasty pain scores for the WOMAC pain subscale, the site of joint arthroplasty and sex for the first composite pain score, and sex for the second composite.