Activity Limitations In Patients Research Articles

Transcultural adaptation and validation of the Spanish-language version of ACTIVLIM in adults with inherited myopathies using the Rasch model

IntroductionACTIVLIM is an instrument for the measurement of activity limitations in patients with neuromuscular disorders. The aim of this study is to establish a transcultural adaptation and psychometric validation of the Spanish-language version of ACTIVLIM in a sample of Spanish patients with inherited myopathies. Patients and methodA Spanish-language version of ACTIVLIM was developed using the translation/back translation method. The questionnaire was administered to 135 patients with inherited myopathies. The psychometric properties of the questionnaire were assessed using the Rasch model. Floor and ceiling effects were estimated. Unidimensionality was evaluated with a principal component analysis of the residuals of the model, and using infit and outfit statistics. We estimated reliability with the person separation reliability index and invariance with differential item functioning. External construct validity was tested through correlation with the Brooke scale, the Vignos scale, the Functional Independence Measure scale, and floor-to-stand time. Test–retest reliability was evaluated with the intraclass correlation coefficient and differential item functioning. ResultsThe psychometric analysis of the Spanish-language version of ACTIVLIM demonstrated that floor effect was absent, although a modest ceiling effect was identified. The instrument displayed unidimensionality, good internal consistency, external construct validity, and good test–retest reliability. ConclusionThe Spanish-language version of ACTIVLIM is a valid and reliable measurement instrument for assessing activity limitations in patients with inherited myopathies.

A multivariate prognostic model for pain and activity limitation in people undergoing lumbar discectomy

Purpose: The purpose of this study was to identify a multivariate predictive model for 6-month outcomes on overall pain, leg pain and activity limitation in patients undergoing lumbar discectomy. Identification of predictors of outcome for lumbar discectomy has the potential to assist identifying treatment targets, clinical decision making and disease understanding.Materials and methods: Prospective cohort design. Ninety-seven patients deemed by study surgeons to be suitable for lumbar discectomy completed a comprehensive clinical and radiological baseline assessment. At 6-months post surgery outcome measures of overall and leg pain (visual analogue scale) as well as activity limitation (Oswestry Disability Index) were completed. Univariate and multivariate analyses were conducted to determine the best multivariate predictive model of outcome.Results: In the multivariate model, presence of a compensation claim, longer duration of injury and presence of below knee pain and/or parasthesia were negative prognostic indicators for at least two of the outcomes. Peripheralization in response to mechanical loading strategies was a positive prognostic indicator for overall pain and leg pain. A range of other prognostic indicators for one outcome were also identified. The prognostic model explained up to 32% of the variance in outcome.Conclusions: An 11-factor prognostic model was identified from a range of clinically and radiologically assessed variables in accordance with a biopsychosocial model. The multivariate model has potential implications for researchers and practitioners in the field. Further high quality research is required to externally validate the prognostic model, evaluate effect of the identified prognostic factors on treatment effectiveness and explore potential mechanisms of effect.

Decreased Pain and Improved Dynamic Knee Instability Mediate the Beneficial Effect of Wearing a Soft Knee Brace on Activity Limitations in Patients With Knee Osteoarthritis.

ObjectiveTo evaluate whether improvement of proprioception, pain, or dynamic knee instability mediates the effect of wearing a soft knee brace on activity limitations in patients with knee osteoarthritis (OA).MethodsWe conducted an analysis of data for 44 patients with knee OA who were enrolled in a laboratory‐based trial evaluating the effect of wearing a commercially available soft knee brace. Activity limitations were assessed with the 10‐meter walk test and the Get Up and Go test. Knee joint proprioception was assessed by an active joint position sense test; pain was assessed on a numeric rating scale (NRS) (range 0–10); pressure pain threshold (PPT) was assessed with a hand‐held pressure algometer; dynamic knee instability was expressed by the perturbation response, i.e., a measure reflecting a deviation in mean knee varus–valgus angle after a controlled mechanical perturbation on a treadmill, with respect to level walking. Mediation analysis was conducted using the product of coefficients approach. Confidence intervals were calculated with a bootstrap procedure.ResultsA decrease in pain (scored on an NRS) and a decrease in dynamic knee instability mediated the effect of wearing a soft knee brace on the reduction of activity limitations (P < 0.05), while changes in proprioception and PPT did not mediate this effect (P > 0.05).ConclusionThis study shows that decreased pain and reduced dynamic knee instability are pathways by which wearing a soft knee brace decreases activity limitations in patients with knee OA.

Cardiovascular disease is associated with activity limitations in osteoarthritis patients

Background: To investigate the associations between Cardiovascular Disease (CVD) and Cardiovascular (CV) risk factors with activity limitations in patients with knee or hip Osteoarthritis (OA). Methods and Findings: Consecutive patients were included from the Amsterdam Osteoarthritis cohort. A questionnaire assessed CVD and its risk factors and subsequently were confirmed by medical file review. The WOMAC-physical functioning subscale (PF), stair-climb tests and the Get Up and Go (GUG) were used to assess activity limitations. The associations of CVD and CV risk factors with activity limitations, adjusted for sex, age and disease severity were calculated using regression analyses. CVD was reported by 64 out of 447 patients (14%); 32 out of 148 men (22%) and 32 out of 299 women (11%). CV risk factors were reported in 9% (smoking) to 82 % (overweight) of the patients. CVD and the CV risk factors hypertension, hypercholesterolemia, diabetes mellitus and obesity were associated with a worse performance score on the GUG and stair-climb test. Women with CVD took 51% longer on the Get up and Go test (16.0 vs. 10.6 seconds). Both men and women with CVD performed significantly worse on the stair climb descent test (6.8 vs. 5.3 for men, and 11.3 vs. 7.1 for women). Conclusions: Patients with knee or hip OA show more activity limitations in association with CVD or CV risk factors. An intervention approach to improve daily functioning in the subgroup of patients with knee or hip osteoarthritis tailored to these patients’ CVD and CV risk factors is warranted.

Cross-Cultural Adaptation, Validity, and Reliability Study of the Turkish Version of Back Performance Scale.

Validation of a performance scale. The purpose of this study is to investigate adaptation, validity, and reliability of the Turkish version of the Back Performance Scale (BPS). Low back pain affects people of all ages and causes pain, disability, and psychosocial problems. BPS is a condition-specific performance measure of activity limitation in patients with low back pain. The purpose of this study is to investigate the cross-cultural adaptation, validity, and reliability of the Turkish version of the BPS. The study included 180 patients with low back pain. For the reliability assessment of the scale, test-retest, and internal consistency analyses were performed. The results of the test-retest analysis were analyzed by Intraclass Correlation Coefficient (ICC) method. For the internal consistency, Cronbach Alpha value was calculated and to construct validity, total points of the BPS were compared with the total points of Roland Morris Disability Questionnaire (RMDQ) and Oswestry Disability Index (ODI) using Pearson correlation coefficient analysis. BPS was found to have high internal consistency (Cronbach alpha value 0.827). Test-retest results were found highly correlated (range from 0.723 to 0.899). Factor analysis indicated that the scale had one factor. BPS is well correlated with RMDQ and ODI (Pearson correlation coefficient with RMDQ 0.576 and with ODI 0.603). The Turkish version of BPS is valid and reliable. 3.

Validation of the shortened Hunter Syndrome-Functional Outcomes for Clinical Understanding Scale (HS-FOCUS)

BackgroundThe rare disease, Hunter Syndrome (mucopolysaccharidosis type II; MPS II), characterized by iduronate-2-sulfatase deficiency, has heterogeneous symptoms often including cognitive impairment (CI). To evaluate physical functioning and daily activity limitations of patients with MPS II, the multidomain shortened Hunter Syndrome-Functional Outcomes for Clinical Understanding Scale (HS-FOCUS) questionnaire was previously developed and preliminarily validated. Here we gather data in a dedicated prospective longitudinal observational study using direct responses to the shortened instrument and assess its psychometric properties further.MethodsInterview data were collected from eligible self-reporting patients (≥ 12 years of age) or caregivers of patients using respective versions of the instrument at baseline and 2–4 weeks later. Internal consistency, test–retest reliability, convergent and discriminant validity, and validity of known groups were assessed. Participants also completed Child Health Questionnaire (CHQ), Health Utilities Index Mark 3, and Global Impression of Severity (GIS) questionnaires.ResultsAll patients were male, consisting of 31 caregiver-reported patients (aged 3–26 years) and 20 self-reported patients (aged 12–58 years). Most (77.4%) caregiver-reported patients had CI. Both questionnaire versions demonstrated good internal consistency and test–retest reliability; Cronbach’s alpha and intra-class correlation coefficients were > 0.70. Spearman’s correlations demonstrated good convergent validity with moderate (> 0.3) to high (> 0.6) correlations of the HS-FOCUS total score with physical functioning, role/social–physical, and bodily pain domains of CHQ. The tool also differentiated between MPS II severity levels based on GIS scores.ConclusionsThe shortened HS-FOCUS questionnaire was found to be a valid and reliable tool to assess the physical functioning impact of MPS II.

ACTIVLIM: adaptación transcultural al castellano y validación en adultos con miopatías hereditarias utilizando el modelo Rasch

IntroductionACTIVLIM is an instrument for the measurement of activity limitations in patients with neuromuscular disorders. The aim of this study is to establish a transcultural adaptation and psychometric validation of the Spanish-language version of ACTIVLIM in a sample of Spanish patients with inherited myopathies. Patients and methodA Spanish-language version of ACTIVLIM was developed using the translation/back translation method. The questionnaire was administered to 135 patients with inherited myopathies. The psychometric properties of the questionnaire were assessed using the Rasch model. Floor and ceiling effects were estimated. Unidimensionality was evaluated with a principal component analysis of the residuals of the model, and using infit and outfit statistics. We estimated reliability with the person separation reliability index and invariance with differential item functioning. External construct validity was tested through correlation with the Brooke scale, the Vignos scale, the Functional Independence Measure scale, and floor-to-stand time. Test-retest reliability was evaluated with the intraclass correlation coefficient and differential item functioning. ResultsThe psychometric analysis of the Spanish-language version of ACTIVLIM demonstrated that floor effect was absent, although a modest ceiling effect was identified. The instrument displayed unidimensionality, good internal consistency, external construct validity, and good test-retest reliability. ConclusionThe Spanish-language version of ACTIVLIM is a valid and reliable measurement nstrument for assessing activity limitations in patients with inherited myopathies.

Development of a Multivariate Prognostic Model for Pain and Activity Limitation in People With Low Back Disorders Receiving Physiotherapy

ObjectiveTo identify predictors for back pain, leg pain, and activity limitation in patients with early persistent low back disorders (LBDs). DesignProspective inception cohort study. SettingPrimary care private physiotherapy clinics in Melbourne, Australia. ParticipantsIndividuals (N=300) aged 18-65 years with low back and/or referred leg pain of ≥6 weeks and ≤6 months duration. InterventionsNot applicable. Main Outcome MeasuresNumeric rating scales for back pain and leg pain as well as the Oswestry Disability Scale. ResultsPrognostic factors included sociodemographics, treatment related factors, subjective/physical examination, subgrouping factors, and standardized questionnaires. Univariate analysis followed by generalized estimating equations were used to develop a multivariate prognostic model for back pain, leg pain, and activity limitation. Fifty-eight prognostic factors progressed to the multivariate stage where 15 showed significant (P<.05) associations with at least 1 of the 3 outcomes. There were 5 indicators of positive outcome (2 types of LBD subgroups, paresthesia below waist, walking as an easing factor, and low transversus abdominis tone) and 10 indicators of negative outcome (both parents born overseas, deep leg symptoms, longer sick leave duration, high multifidus tone, clinically determined inflammation, higher back and leg pain severity, lower lifting capacity, lower work capacity, and higher pain drawing percentage coverage). The preliminary model identifying predictors of LBDs explained up to 37% of the variance in outcome. ConclusionsThis study evaluated a comprehensive range of prognostic factors reflective of both the biomedical and psychosocial domains of LBDs. The preliminary multivariate model requires further validation before being considered for clinical use.

Effects of Sacubitril/Valsartan on Physical and Social Activity Limitations in Patients With Heart Failure

Health-related quality of life (HRQL) of patients with heart failure is markedly reduced compared with that in patients with other chronic diseases, demonstrating substantial limitations in physical and social activities. In the Prospective Comparison of ARNI With an ACE-Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial, sacubitril/valsartan improved overall HRQL compared with enalapril, as determined by the Kansas City Cardiomyopathy Questionnaire (KCCQ). To examine the effects of sacubitril/valsartan on physical and social activities. The PARADIGM-HF trial was a randomized, double-blind, active treatment-controlled clinical trial performed from December 8, 2009, to March 31, 2014, in 8399 patients with New York Heart Association class II to IV disease and a left ventricular ejection fraction of 40% or less at 1043 centers in 38 countries. Data analysis was performed from August 1, 2017, to December 25, 2017. Sacubitril/valsartan, 200 mg twice daily, or enalapril, 10 mg twice daily. Patients completed HRQL assessments using the KCCQ at randomization, 4-month, 8-month, and annual visits. The effect of sacubitril/valsartan on components of the physical and social limitation sections of the KCCQ at 8 months and longitudinally and related biomarkers and clinical outcomes were studied. At baseline, 7618 of 8399 patients (90.7%) (mean [SD] age, 64 [11] years; 5987 [78.6%] male and 1631 [21.4%] female) completed the initial KCCQ assessment. Patients reported the greatest limitations at baseline in jogging and sexual relationships. Patients receiving sacubitril/valsartan had significantly better adjusted change scores in most physical and social activities at 8 months and during 36 months compared with those receiving enalapril. The largest improvement over enalapril was in household chores (adjusted change score difference, 2.35; 95% CI, 1.19-3.50; P < .001) and sexual relationships (adjusted change score difference, 2.72; 95% CI, 0.97-4.46; P = .002); both persisted through 36 months (overall change score difference, 1.69 [95% CI, 0.78-2.60], P < .001; and 2.36 [95% CI, 1.01-3.71], P = .001, respectively). In patients with heart failure with reduced ejection fraction, sacubitril/valsartan significantly improved nearly all KCCQ physical and social activities compared with enalapril, with the largest responses in household chores and sexual relationships. In addition to reduced likelihood of cardiovascular death, all-cause mortality, and heart failure hospitalization, sacubitril/valsartan may improve limitations in common activities in these patients. clinicaltrials.gov Identifier: NCT01035255.

Activity Limitations in Patients with Axial Spondyloarthritis: A Role for Fear of Movement and (Re)injury Beliefs.

To determine whether fear of movement and (re)injury [FOM/(R)I] beliefs, measured with the Tampa Scale for Kinesiophobia 11-item version (TSK-11), influence activity limitations and mediate the relationship between pain severity and activity limitations in axial spondyloarthritis (axSpA). In 173 patients with axSpA, these data were collected: sex, body mass index, disease duration, medication, activity limitations (BASFI; Bath Ankylosing Spondylitis Functional Index), disease activity [Bath Ankylosing Spondylitis Disease Activity Index (BASDAI); BASDAIinf, items 5 and 6; BASDAIpain, items 2 and 3; C-reactive protein and physician's global assessment], spinal mobility (BASMI; Bath Ankylosing Spondylitis Metrology Index), and FOM/(R)I (TSK-11). Scaling assumptions and reliability of TSK-11 were tested with item-to-total correlations, item variances, and Cronbach's alpha coefficient. Hypothesis testing determined TSK-11's construct validity. Multiple linear regression showed the contribution of TSK-11 to BASFI (enter and backward modeling). Mediation by TSK-11 was analyzed (bias-corrected bootstrapping and Sobel test). Adequate scale (Cronbach's alpha = 0.80) and item internal consistency (range item-scale correlations 0.41-0.58, except for item 5, r = 0.23), equal item-scale correlations, and item variances were found for TSK-11. Construct validity was confirmed, except for the hypothesized positive relationship between TSK-11 and BASMI. Regression models (enter method, adjusted R2 range 53-74%) consistently identified TSK-11 as a determinant of BASFI (β range 0.155 to 0.321, p < 0.05), although BASMI (β range 0.441 to 0.537) and disease activity (β range 0.243 to 0.571, p < 0.05) were the largest determinants. TSK-11 partially mediated the BASDAIpain/BASFI relationship (B = 0.107; Sobel test, p = 0.004; bias-corrected CI 0.046-0.197). TSK-11 is a promising and valid tool to assess fearful beliefs in relation to activity limitations in axSpA. Future research applying TSK-11 may reveal FOM/(R)I as a novel treatment target in axSpA.

Novel insights of disability assessment in adult myositis.

To review the novel development of standardized clinical outcome measures used in adult patients with idiopathic inflammatory myopathies (IIMs). A further aim was to determine what aspects of IIM are covered by these outcome measures according to the International Classification of Functioning, Disability and Health (ICF). The sporadic inclusion body myositis functional assessment (sIFA) is the first diagnosis-specific patient-driven patient-reported outcome measure. The adult myositis assessment tool (AMAT) is a new outcome measure assessing physical performance. Also, new criteria to assess response to treatment have been presented for both adults and children with IIM. The ICF provides a standardized frame and structure to report outcome, including functional disability. Using this framework, it is evident that there is a lack of validated patient-reported outcome measures to assess disease aspects important to patient, and that no studies have evaluated life-style factors such as physical activity in these patients. The sIFA will ensure patient-relevant patient-reported assessment of activity limitations in patients with inclusion body myositis. The AMAT is a partly validated tool that needs to be used in clinical trials for further validation. The response criteria will enhance assessment of individual response to different treatments.

Cross-Cultural and Construct Validity of the Animated Activity Questionnaire.

The Animated Activity Questionnaire (AAQ) assesses activity limitations in patients with hip/knee osteoarthritis and consists of video animations; the patients choose the animation that best matches their own performance. The AAQ has shown good validity and reliability. This study aims to evaluate cross-cultural and construct validity of the AAQ. Cross-cultural validity was assessed using ordinal logistic regression analysis to evaluate differential item functioning (DIF) across 7 languages. Construct validity was assessed by testing correlations between the AAQ and a patient-reported outcome measure (PROM) and performance-based tests. Data from 1,239 patients were available. Compared to the Dutch language (n = 279), none of the 17 items showed DIF in English (n = 202) or French (n = 193), 1 item showed uniform DIF in Spanish (n = 99) and Norwegian (n = 62), and 2 items showed uniform DIF in Danish (n = 201). In all these languages, the occurrence of DIF did not influence the total score, which remained comparable with the original Dutch version. For Italian (n = 203) versus Dutch, however, 6 items showed uniform DIF, and 1 item showed nonuniform DIF, indicating some problems with the cross-cultural validity between these countries. With regard to construct validity, the correlations with PROM (0.74) and performance-based tests (0.36-0.68) were partly as expected (>0.60). The AAQ, an innovative tool to measure activity limitations that can be placed on the continuum between PROMs and performance-based tests, showed a good overall cross-cultural validity, and seems to have great potential for international use in research and daily clinical practice in many European countries.

Nonlinear relationship between isokinetic muscle strength and activity limitations in patients with knee osteoarthritis: Results of the Amsterdam-Osteoarthritis cohort.

To investigate whether relationships between upper leg muscle strength and activity limitations are non-linear in patients with knee osteoarthritis, and, if so, to determine muscle strength thresholds for limitations in daily activities. Baseline data were used for 562 patients with knee osteoarthritis in the Amsterdam-Osteoarthritis cohort. Upper leg muscle strength (Nm/kg) was measured isokinetically. Activity limitations were measured with the timed Get Up and Go test and timed Stair Climb Test, subdivided into stair-ascent and stair-descent. Linear and non-linear relationships between muscle strength and activity limitations were evaluated, and thresholds were determined. Non-linear models improved model fit compared with linear models. The improvement in percentage variance accounted for was 5.9, 8.2 and 5.2 percentage points for the timed Get Up and Go, stair-ascent and stair-descent times, respectively. Muscle strength thresholds were 0.93 Nm/kg (95% confidence interval (95% CI) 0.82-1.04), 0.89 Nm/kg (95% CI 0.77-1.02) and 0.97 Nm/kg (95% CI 0.85-1.11) for relationships with timed Get Up and Go, stair-ascent and stair-descent times, respectively. In patients with knee osteoarthritis, relationships between muscle strength and activity limitations are non-linear. Patients with muscle strength below the described thresholds might benefit more from muscle strength training to reduce limitations in daily activities than would patients with muscle strength above the thresholds. Further research is needed to assess the clinical value of the thresholds determined.

Upper-Limb Recovery After Stroke

Background and purpose. This study compared the effect of cyclic neuromuscular electrical stimulation (NMES), electromyographically (EMG)-triggered NMES, and sensory stimulation on motor impairment and activity limitations in patients with upper-limb hemiplegia. Methods. This was a multicenter, single-blind, multiarm parallel-group study of nonhospitalized hemiplegic stroke survivors within 6 months of stroke. A total of 122 individuals were randomized to receive either cyclic NMES, EMG-triggered NMES, or sensory stimulation twice every weekday in 40-minute sessions, over an 8 week-period. Patients were followed for 6 months after treatment concluded. Results. There were significant increases in the Fugl-Meyer Assessment [F(1, 111) = 92.6, P < .001], FMA Wrist and Hand [F(1, 111) = 66.7, P < .001], and modified Arm Motor Ability Test [mAMAT; time effect: F(1, 111) = 91.0, P < .001] for all 3 groups. There was no significant difference in the improvement among groups in the FMA [F(2, 384) = 0.2, P = .83], FMA Wrist and Hand [F(2, 384) = 0.4, P = .70], or the mAMAT [F(2, 379) = 1.2, P = .31]. Conclusions. All groups exhibited significant improvement of impairment and functional limitation with electrical stimulation therapy applied within 6 months of stroke. Improvements were likely a result of spontaneous recovery. There was no difference based on the type of electrical stimulation that was administered.

The association between muscle strength and activity limitations in patients with the hypermobility type of Ehlers–Danlos syndrome: the impact of proprioception

Purpose: The patients diagnosed with Ehlers–Danlos Syndrome Hypermobility Type (EDS-HT) are characterized by pain, proprioceptive inacuity, muscle weakness, potentially leading to activity limitations. In EDS-HT, a direct relationship between muscle strength, proprioception and activity limitations has never been studied. The objective of the study was to establish the association between muscle strength and activity limitations and the impact of proprioception on this association in EDS-HT patients.Methods: Twenty-four EDS-HT patients were compared with 24 controls. Activity limitations were quantified by Health Assessment Questionnaire (HAQ), Six-Minute Walk test (6MWT) and 30-s chair-rise test (30CRT). Muscle strength was quantified by handheld dynamometry. Proprioception was quantified by movement detection paradigm. In analyses, the association between muscle strength and activity limitations was controlled for proprioception and confounders.Results: Muscle strength was associated with 30CRT (r = 0.67, p = <0.001), 6MWT (r = 0.58, p = <0.001) and HAQ (r = 0.63, p= <0.001). Proprioception was associated with 30CRT (r = 0.55, p < 0.001), 6MWT (r = 0.40, p = <0.05) and HAQ (r = 0.46, p < 0.05). Muscle strength was found to be associated with activity limitations, however, proprioceptive inacuity confounded this association.Conclusions: Muscle strength is associated with activity limitations in EDS-HT patients. Joint proprioception is of influence on this association and should be considered in the development of new treatment strategies for patients with EDS-HT.Implications for rehabilitationReducing activity limitations by enhancing muscle strength is frequently applied in the treatment of EDS-HT patients. Although evidence regarding treatment efficacy is scarce, the current paper confirms the rationality that muscle strength is an important factor in the occurrence of activity limitations in EDS-HT patients.Although muscle strength is the most dominant factor that is associated with activity limitations, this association is confounded by proprioception. In contrast to common belief proprioception was not directly associated with activity limitations but confounded this association. Controlling muscle strength on the bases of proprioceptive input may be more important for reducing activity limitations than just enhancing sheer muscle strength.

Nonlinearity and thresholds in the relationship between muscle strength and activity limitations in patients with knee osteoarthritis: results of the amsterdam-osteoarthritis cohort

Nonlinearity and thresholds in the relationship between muscle strength and activity limitations in patients with knee osteoarthritis: results of the amsterdam-osteoarthritis cohort

Cross-cultural validation of the computerized animated activity questionnaire to assess activity limitations in patients with hip and knee osteoarthritis

Purpose: The computerized Animated Activity Questionnaire (AAQ) for assessing activity limitations in hip and knee osteoarthritis (HKOA) consists of video animations from which patients can choose the animation that best matches their own performance. The AAQ has demonstrated good validity and reliability. Application of the AAQ in international studies, requires good cross-cultural validity, i.e., minimal Differential Item Functioning (DIF) across countries. The aim of this study was to evaluate cross-cultural validity. Methods: Patients in 7 European countries patients completed the AAQ on a computer. Ordinal logistic regression analysis was used to evaluate DIF across languages (Dutch versus 6 other languages). DIF is defined as follows: If a patient in a country has the same level of activity limitation as a patient in the Netherlands (the reference country in which the AAQ is developed), they should score the same on each item of the AAQ. If there is a statistical significant difference between countries, there is DIF. We used frequently described criteria in literature to assess DIF between countries. Criteria for non-uniform DIF were set as a statistical significance (p <0.001) pseudo R-square change according to Nagelkerke with a magnitude larger than 0.035 between the AAQ total score and the country variable (with Dutch as the reference group). Criteria for uniform DIF were set as a statistical significant (p <0.001) odds ratio (OR) of the country variable with a magnitude outside the interval 0.53-1.89. Analyses were adjusted for sex, age, weight, height, and affected joint. The influence of each individual item with DIF on the total score was calculated by means of comparing the correlation between AAQ score with and without the DIF item. A Spearman's correlation of 0.95 or less was interpreted as important influence of the DIF of that item on the total AAQ score. Results: Data of 1239 patients were available. Compared to Dutch (n = 279), none of the 17 items showed DIF in English (n = 202) and French (n = 193). Uniform DIF occurred in the activity 'walking outside' for Spanish versus Dutch (OR 0.28) and Norwegian versus Dutch (OR 0.16), with for both countries scores representing slightly worse functioning compared to Dutch. For Danish versus Dutch, DIF occurred in two items (walking outside on uneven terrain; OR 0.45, walking inside; OR 0.43), also representing slightly worse functioning compared to Dutch. In all these languages, the occurrence of DIF did not influence the total score with correlations of 0.98-0.99 in comparing AAQ scores with and without DIF item (s). For Italian (n = 203) versus Dutch, 6 items showed uniform DIF and 1 item showed non-uniform DIF, which makes it difficult to compare scores obtained in those two countries. Conclusions: Different language versions of the AAQ remain comparable with the original Dutch version except for the Italian version. The AAQ seems to have great potential for international use in research and daily clinical practice, especially in patients with low literacy and non-native speakers, because the use of video animations instead of written text. Future research will focus on responsiveness, interpretation of AAQ scores, and should explore explanations for DIF in Italy by means of qualitative research.

Ratings of pain and activity limitation on the visual analogue scale and global impression of change in multimodal rehabilitation of back pain – analyses at group and individual level

Purpose: To evaluate changes in pain intensity and activity limitation, at group and individual levels, and their associations with the global impression of change after multimodal rehabilitation in patients with back pain.Method: Patients with long-term back pain (n = 282) participated in a 4-week programme with a follow-up after 6 months. Visual analogue scales (VAS) were used to rate pain intensity and activity limitation. Global impression of change (GIC) was rated on a 7-category scale. The sign test, the Svensson method and the Spearman rank correlation were used for analyses.Results: Significantly lower ratings in pain and activity limitation at follow-up were found at group level. However, a large individual variability was found by the Svensson method. The correlations between GIC and changes in pain and activity limitation were rs = 0.49 and rs = 0.50, respectively. A rated GIC of at least “much better” on group level showed changes of ≥20 mm on the VAS.Conclusions: At group level, lower VAS ratings were found in patients with back pain. However, a large individual variability in pain and activity limitation was also found resulting in low to moderate associations between GIC and the change in VAS ratings. The large individual variability might be due to the impreciseness in the ratings on the VAS. We have presented a critical discussion of statistical methods in connection with the VAS.Implications for RehabilitationThe use of VAS as a rating instrument may be questioned, especially for perceived pain intensity which is a too complex experience to be rated on a line without any visible categories.Single ratings of pain intensity should preferably be complemented with the ratings of activity limitation in patients with long-term back pain.Global impression of change is a suggested inclusive rating after rehabilitation.The improvement desired by the patient should preferably be determined before rehabilitation.

失語症患者の言語・認知機能障害とコミュニケーション活動制限の経時的変化 ──WAB失語症検査と短縮版CADL検査を用いた検討──

失語症患者の言語・認知機能障害とコミュニケーション活動制限の経時的変化 ──WAB失語症検査と短縮版CADL検査を用いた検討──

How robust is ACTIVLIM for the follow-up of activity limitations in patients with neuromuscular diseases?

This study aims to investigate the clinimetric properties of ACTIVLIM, a measure of activity limitations, when it is used in daily practice in a large nationwide representative cohort of patients with neuromuscular diseases. A cohort of 2986 patients was assessed at least once over 2 years in 6 national neuromuscular diseases reference centers. Successive Rasch analyses were conducted in order to investigate the scale validity, reliability, consistency across demographic and clinical sub-groups and its sensitivity to change. ACTIVLIM confirmed excellent fit to a unidimensional scale, with stable but 3-times more accurate item calibrations compared to the original publication. It showed a good reliability (R = 0.95), an appropriate targeting for 87% of the sample and an excellent invariance across age, gender, language and time. Despite some variations in the item difficulty hierarchy across diagnoses, ACTIVLIM exhibited a good capability to quantify small but significant changes in activity for various diagnostic groups. Overall, ACTIVLIM demonstrated very good clinimetric properties, allowing accurate quantitative measurement of activity limitations in both children and adults with a variety of neuromuscular diseases.