Rasch validation of the German version of the Prosthesis Embodiment Scale for lower limb amputees and proposal of a revised version.

PURPOSE: To perform a detailed psychometric Rasch analysis of the Prosthesis Embodiment Scale (PEmbS) administered in adults with lower limb amputation (LLA). METHODS: A convenience sample of German-speaking adults with LLA (n = 150), recruited from German state agencies' databases, was asked to complete the PEmbS, a 10-item patient-reported scale assessing prosthesis embodiment. RESULTS: The local dependency between two items was resolved by keeping for the global score only the lower score of these two items (#9 and #10). Collapsing the seven response categories to four (two expressing disagreement and two agreement) eliminated disordered thresholds. After that, the PEmbS demonstrated unidimensionality, acceptable item fit, and good reliability indices. A keyform plot was created to transform raw scores into linear measures of prosthesis embodiment, making it possible to compare the individual's item responses with those expected by the Rasch model, and to manage missing responses. CONCLUSIONS: The PEmbS is useful for assessing prosthesis embodiment in people with LLA, both for research and clinical purposes. We propose a revised version of the PEmbS for lower limb amputees; its appropriateness in other LLA contexts requires further investigation.

Prosthesis embodiment has been empirically related to positive clinical outcomes in limb amputees.The Prosthesis Embodiment Scale (PEmbS) is a patient-reported scale that has been recently recommended for use in research on prosthesis embodiment.Rasch analysis showed that the revised version of the German PEmbS is a psychometrically sound instrument for the assessment of prosthesis embodiment in lower limb amputees.The PEmbS thus also allows reliable and valid diagnosis of prosthesis embodiment in clinical and rehabilitation contexts.

Categorization and recommendations for outcome measures for lower limb absence by an expert panel.

BACKGROUND: Understanding the psychometric strengths and limitations of outcome measures for use with people with lower limb absence (LLA) is important for selecting measures suited to evaluating patient outcomes, answering clinical and research questions, and informing health care policy. The aim of this project was to review the current psychometric evidence on outcome measures in people with LLA to determine which measures should be included in a stakeholder consensus process. METHODS: An expert panel was assembled, and a 3-stage review process was used to categorize outcome measures identified in a systematic literature review into 3 distinct categories (recommended for measures with better than adequate psychometric properties; recommended with qualification; and unable to recommend). Panelists were asked to individually categorize measures based on results of a systematic review of identified measures' psychometric properties. Each measure's final categorization was based on ≥70% agreement by all panelists. RESULTS: No outcome measure attained the ≥70% consensus threshold needed to achieve a rating of "recommend." Hence, panelists suggested combining "recommend" and "recommend with qualifications" into a single category of "recommend with qualifications." Using this approach, consensus was reached for 59 of 60 measures. Consensus could not be reached on 1 outcome measure (socket comfort score). Thirty-six outcome measures were categorized as "unable to recommend" based on available evidence; however, 23 (12 patient-reported measures and 11 performance-based measures) demonstrated adequate psychometric properties in LLA samples and were thus rated as "recommend with qualification" by the expert panel. The panel of experts were able to recommend 23 measures for inclusion in the subsequent stakeholder review. A key strength of this process was bringing together international researchers with extensive experience in developing and/or using LLA outcome measures who could assist in identifying psychometrically sound measures to include in a subsequent stakeholder consensus process. CONCLUSION: The above categorizations represent the current state of psychometric evidence on outcome measures for people with LLA and hence may change over time as additional research becomes available. The results will be used to achieve wider consensus from clinicians, health policymakers, health clinic managers, researchers, and end users (i.e., individuals with LLA) on outcome measures for the International Society of Prosthetics and Orthotics lower limb Consensus Outcome Measures for Prosthetic and Amputation ServiceS.

Rasch validation of the German translation of the Prosthetic Limb Users Survey of Mobility short forms in people with lower limb amputation.

BACKGROUND: Prostheses are a primary rehabilitative intervention for people after lower limb amputation. To appropriately measure the effectiveness of prosthetic interventions, valid and reliable measures of prosthetic mobility are required. The Prosthetic Limb Users Survey of Mobility (PLUS-M) is a promising instrument for measuring prosthesis users' mobility. However, German translations of the PLUS-M short forms have not yet been validated. OBJECTIVES: Rasch validation of the German translation of the PLUS-M short forms in people with lower limb amputation. STUDY DESIGN: This study is based on a cross-sectional survey of prosthesis-using lower limb amputees from a nation-wide cohort. METHODS: PLUS-M data (the 7-item and the 12-item shortforms; PLUS-M-7 and PLUS-M-12, respectively) from 194 lower limb prosthesis users were subjected to Rasch analysis, an advanced statistical method for assessing if the measurement properties of a questionnaire comply with a wide spectrum of psychometric requirements. RESULTS: Analysis showed appropriate rating scale functioning, good internal construct validity (item fit), unidimensionality, and good targeting of the PLUS-M-7 and PLUS-M-12 short forms. Moreover, the greater conditional measurement precision of PLUS-M-12 (regarding higher test information and lower standard error of mobility estimates) was quantified. CONCLUSIONS: Rasch analysis of the German translation of both PLUS-M short forms showed good psychometric qualities. In addition, our study showed that test scores from the PLUS-M-12 are more accurate. Therefore, the PLUS-M-12 is recommended for individual-level clinical applications (e.g., classification or change assessment).

Assessing individual-level measurement precision of the Short Physical Performance Battery using the test information function.

The Short Physical Performance Battery (SPPB) is a commonly used tool to assess lower extremity function, composed of three assessments (standing balance, gait speed, and chair stand). While its validity for group-level decisions has been positively demonstrated, the measurement precision at the individual level needs more clarification. We aimed to examine the SPPB's psychometric characteristics including its conditional measurement precision with Rasch methods in a sample of elderly patients admitted to cardiac rehabilitation. We analyzed prospectively collected SPPB data from 637 patients aged ≥75 years, admitted to our cardiac rehabilitation department (January 2018-July 2019). After classical Rasch analysis, we calculated the test information function to examine the measurement precision of the SPPB along the score continuum. The mean SPPB score was 6.3 points (SD 3.4) (potential range 0-12). Our results confirmed the SPPB unidimensionality (variance attributable to the main factor: 84.8%), appropriate functioning of rating scale categories, internal construct validity (infit and outfit mean-square statistics: 0.90-1.09), and no item local dependence (residual correlations <0.2). However, the measurement precision at the individual level was quite limited (SE > 0.94 logits): the confidence intervals for true scores were, at best, about one-third of the score range (four points). This limited measurement precision increases the risk of inappropriate clinical decisions about individuals in diagnostic classification or change assessment. Therefore, further research of high methodological quality is warranted on this point. Moreover, a clearer distinction between group-level vs. individual-level indicators of change is necessary.

Rasch validation and refinement of the Lymphedema Life Impact Scale version 2 in an Italian cohort with secondary lymphedema.

PURPOSE: To produce and validate an Italian version of the Lymphedema Life Impact Scale version 2 (LLISv2-It), a tool measuring the impact of lymphedema on health-related quality of life, and investigate its main psychometric characteristics. METHODS: After translation and cross-cultural adaptation of the LLISv2, we administered it to 156 subjects with secondary lymphedema (upper or lower limb), together with (depending on the limb involved) either the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) or the Lower Extremity Functional Scale (LEFS). We analyzed the performance of LLISv2-It using Classical Test Theory and Rasch methods. RESULTS: Cronbach alpha was 0.89. Item fit statistics indicated that item #12 was underfitting (Infit MnSQ = 1.56; Outfit MnSq = 1.75). Test-retest reliability of the 17-item version (without item #18, not scored, according to the original authors) and of a 16-item version (without #12 and #18-a unidimensional item set) were both excellent (ICC2.1 = 0.93; 95%). The minimum detectable change was 8.9 points. The correlation of LLISv2-It with DASH and LEFS was r = 0.81 and -0.57, respectively. CONCLUSIONS: The Italian version of the LLISv2 is reliable and valid. To make the tool more psychometrically sound, we recommend to not calculate items #12 and #18 in the total score.IMPLICATIONS FOR REHABILITATIONThe Lymphedema Life Impact Scale (LLISv2) is particularly useful as a validated condition-specific health-related quality of life measure for patients with chronic edema/lymphedema. We have validated its Italian version (LLISv2-It).We also examined the psychometric properties of the LLISv2 in individuals with secondary lymphedema of either upper or lower limb, using both classical test theory and Rasch techniques, to provide insights for further refinement of the questionnaire.Based on our results, we recommend not to count item #12 in the total score (besides #18, as already suggested by the original authors). Moreover, we determined that the minimum detectable change of the LLISv2 was 9 points. This information is helpful in clinical practice to understand if the change in score is not due to chance (measurement error).Although further research is warranted, the present validation study of the LLISv2 increases the confidence in the metric quality and clinical utility of the scale to assess lymphedema-specific health-related quality of life in individuals with secondary lymphedema of either upper or lower limb.

Head-to-head Rasch comparison of the Prosthesis Evaluation Questionnaire-Mobility Section and the Prosthetic Mobility Questionnaire 2.0 in Italian lower-limb prosthesis users.

BACKGROUND: The Prosthesis Evaluation Questionnaire-Mobility Section (PEQ-MS) and the Prosthetic Mobility Questionnaire (PMQ 2.0) are two validated self-report questionnaires assessing mobility in people with lower-limb amputation. OBJECTIVE: The aim of this study was to assess and compare the psychometric properties of PEQ-MS and PMQ 2.0 in a sample of 100 Italian lower-limb prosthesis users. METHODS: We conducted a secondary Rasch analysis of data from a prospective single-group observational study, comparing the PEQ-MS and PMQ 2.0 head to head and then cocalibrating them onto a common interval-scaled metric, through common-person equating, to compare their operational range. RESULTS: The PMQ 2.0 showed good measurement qualities. The PEQ-MS had acceptable psychometric properties, despite some weakness in item selection. Cocalibration of the two questionnaires indicated that they assess the same underlying construct (prosthetic mobility), but PMQ 2.0 items have a wider range of difficulty (by one logit). Finally, we created a nomogram allowing to "cross-walk" between scores of the two questionnaires. CONCLUSIONS: Comparison of the two questionnaires showed that the PMQ 2.0 has a better measurement performance and larger operational range than the PEQ-MS, making it more suitable for assessing lower-limb prosthesis users with a large range of locomotor abilities, in particular those with higher mobility levels.

Translation, cross-cultural adaptation, and validation of the Italian version of the Synkinesis Assessment Questionnaire in individuals with peripheral facial palsy.

BACKGROUND: After peripheral facial palsy, the onset of facial synkinesis results in aesthetic disfigurement and local muscle tension or pain, with possible deterioration of patient's well-being and social participation. The availability of valid instruments to evaluate patient-reported severity of facial synkinesis is important to capture the subjective perception of facial impairment. AIM: To generate and validate an Italian version of the Synkinesis Assessment Questionnaire, a patient-reported outcome measure to assess patient-perceived severity of facial synkinesis after peripheral facial palsy. DESIGN: Observational study. SETTING: Outpatient clinic of a Rehabilitation Unit. POPULATION: Seventy-five patients with peripheral facial palsy. METHODS: Through a process of translation and cross-cultural adaptation, we generated the Italian version of the questionnaire (SAQ-IT) and administered it twice to patients with peripheral facial palsy. We evaluated the clinical severity with the Sunnybrook Facial Grading System (SFGS) and the physical and social/well-being function with the two subscales of the Facial Disability Index (FDI-PHY and FDI-SWB, respectively). RESULTS: Cronbach's alpha was 0.87. Item-total correlations ranged from 0.30 to 0.70, while inter-item correlations ranged from 0.15 to 0.82, with an average value of 0.48. Test-retest reliability showed an Intraclass Correlation Coefficient of 0.946 (95% confidence interval: 0.916-0.966). The minimum detectable change (with a 95% confidence level, MDC95) was 13.14 points. The correlation between SAQ-IT and the SFGS synkinesis subscore was rho=0.74, while that with the SFGS composite score was rho=0.25, with the FDI-PHY rho=-0.11 and with the FDI-SWB rho=-0.13. CONCLUSIONS: Our study validates the SAQ-IT in Italian-speaking individuals with peripheral facial palsy, confirming its acceptable psychometric properties, and providing the MDC95. CLINICAL REHABILITATION IMPACT: The availability of a valid instrument for the evaluation of patient-perceived severity of facial synkinesis plays an important role in the definition of tailored rehabilitative interventions after peripheral facial palsy.

Measurement precision of the Pain Catastrophizing Scale and its short forms in chronic low back pain.

The Pain Catastrophizing Scale (PCS) is a widely studied tool to assess pain catastrophizing for chronic low back pain (LBP). Short forms of the PCS exist, but their measurement precision at individual level is unclear. This study aimed to analyze the Rasch psychometric characteristics of the PCS and three of its short forms (two 4-item and one 6-item) in a sample of 180 Italian-speaking patients with chronic LBP, and compare their measurement precision at the individual level. We performed a Rasch analysis on each version of the PCS and calculated test information functions (TIFs) to examine conditional measurement precision. Rasch analysis showed appropriate rating category functioning, unidimensionality, and acceptable fit to the Rasch model for all PCS versions. This represented a prerequisite for performing further advanced psychometric analyses. According to TIFs, the PCS full scale showed-at any score level-higher measurement precision in estimating individual pain catastrophizing than its short forms (which had unacceptably high standard errors of measurement). Our results show acceptable conditional precision of the PCS full scale in estimating pain catastrophizing. However, further studies are needed to confirm its diagnostic accuracy at individual level. On the other hand, the study warns against use of the three PCS short forms for clinical decision-making at the individual level.

Cross-cultural adaptation and validation of the Athlete Fear Avoidance Questionnaire in Italian university athletes with musculoskeletal injuries.

The aim of this study was to translate, culturally adapt and validate an Italian version of the Athlete Fear Avoidance Questionnaire (AFAQ-I). We conducted a cross-sectional evaluation of the psychometric properties of the AFAQ-I in university athletes with musculoskeletal injuries, culturally adapting it in accordance with international standards. Psychometric evaluation included the assessment of structural validity (exploratory factor analysis), internal consistency (Cronbach's alpha and inter-item correlation), test-retest reliability [intraclass correlation coefficient, (ICC) (2,1)], measurement error and minimum detectable change (MDC). To examine construct validity, we compared (Spearman ρ) the AFAQ-I with a numerical pain rating scale (NPRS), the Pain Catastrophizing Scale (PCS) and the Fear Avoidance Beliefs Questionnaire (FABQ) subscales [FABQ-Physical Activity (FABQ-PA) and FABQ-Work (FABQ-W)]. The AFAQ-I was administered to 133 university athletes with musculoskeletal injuries (95 males and 38 females; mean age 25 years, SD 5; mean average pain duration 5.6 months, SD 8.7). Factor analysis revealed an acceptable 1-factor 10-item solution (explained common variance at minimum rank factor analysis: 0.74) although a couple of items (#6 and 9) presented low factor loadings, suggesting the presence of a small secondary dimension. Cronbach's alpha was 0.78 and the average inter-item correlation was 0.27. ICC (2,1) was 0.95 and the MDC was 4.4 points. As hypothesized a priori, the AFAQ-I moderately correlated with NPRS (ρ = 0.42), PCS (ρ = 0.59), FABQ-PA (ρ = 0.40) and FABQ-W (ρ = 0.34). In conclusion, the AFAQ-I is a valid Italian translation of AFAQ that demonstrates acceptable psychometric properties. However, we recommend further analysis of the construct definition of the AFAQ and additional examination of its structural validity.

Rasch Validation of the Mini-BESTest in People With Parkinson Disease.

BACKGROUND AND PURPOSE: The Mini-BESTest is a balance measure with robust psychometric properties widely used in people with Parkinson disease. The aim of this study was to examine-with advanced psychometric techniques-some key properties of the Mini-BESTest (including unidimensionality, functioning of rating categories, internal construct validity, reliability indexes) in a consecutive sample of individuals with Parkinson disease admitted for balance rehabilitation. METHODS: Confirmatory factor analysis and Rasch analysis (partial credit model) were performed on 193 individual raw scores of the Mini-BESTest items. RESULTS: Confirmatory factor analysis fit indices and principal component analysis of the residuals confirmed the scale's unidimensionality. At Rasch analysis, the 3-level rating scale demonstrated appropriate functioning. All items fitted the Rasch model. Item response dependence was negligible. No differential item functioning was found across gender and age groups. DISCUSSION AND CONCLUSIONS: We confirmed and extended the evidence (demonstrated in different populations) on the general psychometric soundness of the Mini-BESTest, even when tested with rigorous statistical methods. In addition, 2 forms were created: (i) to transform raw scores into linear estimates of dynamic balance; and (ii) to compare the individual's item responses with those expected by the Rasch model (thus providing an aid for tailored interventions) and manage missing responses. Further independent studies using advanced psychometric techniques are warranted, also in people with balance disturbances of different etiology. Our study further increases the confidence in using the Mini-BESTest to assess dynamic balance in people with Parkinson disease and provides some useful additional clinical aids for interpreting the results and calculating more precise change scores.See the Supplementary Video, available at: http://links.lww.com/JNPT/A384.

Responsiveness and Minimal Important Change of the Quebec Back Pain Disability Scale in Italian patients with chronic low back pain undergoing multidisciplinary rehabilitation.

BACKGROUND: There is still a lack of information concerning Minimal Important Change (MIC) of the Quebec Back Pain Disability Scale (QBPDS), that limits its use for clinical and research purposes. AIM: Evaluating responsiveness and MIC of the QBPDS in Italians with chronic low back pain (LBP). DESIGN: This is a methodological research based on an observational study. SETTING: Outpatient rehabilitation hospital. POPULATION: Two hundred and one patients with chronic LBP. METHODS: At the beginning and end of a multidisciplinary rehabilitation program, patients completed the QBPDS. At the end of treatment, they completed a 7-level global perceived effect (GPE) scale, which was split to obtain a dichotomous outcome (improved vs. stable). Responsiveness was calculated by distribution-based (effect size [ES]; standardized response mean [SRM]; minimum detectable change [MDC95]) and anchor-based methods (receiver operating characteristics [ROC] curves). ROC curves were also used to compute the MIC (based on QBPDS change score, both absolute and expressed as percentage). Correlations between the change score of the QBPDS and GPE were calculated. RESULTS: The ES was 0.29, the SRM was 0.43, and the MDC95 was 12 points. ROC analysis of the absolute change scores showed a MIC value of 6 points, with an area under the curve (AUC), sensitivity, and specificity of 0.83 (95% CI: 0.77-0.90), 77.7% and 80.8%, respectively. ROC analysis based on the percent change score from baseline revealed a MIC of 18% with an AUC, sensitivity and specificity of 0.85 (95% CI: 0.79-0.91), 80.6% and 80.8%, respectively. Correlation between change score of the QBPDS and GPE was ρ=-0.67. CONCLUSIONS: The QBPDS score change (expressed in both absolute value and percentage from baseline) was sensitive in detecting clinical changes in Italian subjects with chronic LBP undergoing multidisciplinary rehabilitation. In clinical practice, where absolute change is lower than MDC we recommend to rely on the MIC taking into account the percentage change from baseline condition. CLINICAL REHABILITATION IMPACT: The present study investigated the responsiveness and MIC of the QBPDS in a group of patients with chronic LBP. Our findings showed that the QBPDS score may classify with good to excellent discriminatory accuracy subjects who consider themselves as improved. Where examining change, we recommend considering both MICs we provided (expressing score change both in absolute value and as a percentage from baseline), and disregard values lower than MDC95, not being discernible from measurement error.

Lymphedema quality of life questionnaire (LYMQOL): cross-cultural adaptation and validation in Italian women with upper limb lymphedema after breast cancer.

PURPOSE: There is growing interest in measures that assess upper-limb lymphedema after breast cancer. Since no validated Italian version of the Lymphedema Quality of Life Questionnaire for upper limbs (LYMQOL-UL) exists, we aimed to culturally adapt and validate an Italian version (LYMQOL-UL-IT) in order to allow its use in Italian patients. MATERIALS AND METHODS: The LYMQOL-UL-IT was developed by means of forward-backward translation, review by an expert committee and a test of the pre-final version to evaluate its comprehensibility. The psychometric testing included reliability by internal consistency (Cronbach's alpha) and test-retest reliability (intraclass correlation coefficient, ICC(2.1)), measurement error by calculating the minimum detectable change (MDC95), construct validity by confirmatory factor analysis, and evaluation of a priori hypotheses about the correlations between the four LYMQOL-UL domains, single items of the LYMQOL-UL, and measures of health-related quality of life and pain intensity (Spearman's rank correlation coefficient). RESULTS: The consensus-based version of LYMQOL-UL-IT was administered to 139 patients with upper-limb stable secondary iatrogenic lymphedema after breast cancer. The adapted questionnaire was well accepted as it was completed in less than 10 min, without missing answers or comprehension problems. Internal consistency was acceptable (α = 0.92-0.95). Test-retest reliability was good-to-excellent (ICC(2.1) = 0.73-0.96). The MDC95 for the four domains of the questionnaire was as follows: 0.64 scale points for Function, 0.40 for Appearance, 0.53 for Symptoms, and 0.81 for Mood. Factor analysis confirmed a 4-dimensional structure as originally conceived and the a priori hypotheses were met. CONCLUSION: The LYMQOL-UL-IT is reliable, sensitive to change and valid in patients with upper-limb stable secondary iatrogenic lymphedema after breast cancer. It can be used for clinical and research purposes.Implications for rehabilitationLymphedema is a frequently unnoticed clinical condition that not only impacts physical functioning but often restricts the health-related quality of life in breast cancer survivors.The Italian version of the Lymphedema Quality of Life Questionnaire for upper limbs (LYMQOL-UL-IT) is reliable, sensitive to change and valid in patients with upper-limb lymphedema after breast cancer.The LYMQOL-UL-IT tool can be recommended for clinical and research purposes.

Let's Write a Manuscript: A Primer With Tips and Tricks for Penning an Original Article.

ABSTRACT: A group of international researchers and editors summarize how (promptly and easily) an original manuscript can be written using certain tips and tricks. The authors guide novice colleagues with minimal experience using simple hints and straightforward advice in scholarly publishing. The main body of an original article is composed of four parts: Introduction, Methods, Results, and Discussion (the IMRaD format). We make recommendations about how to write these sections. We also make suggestions regarding the title, abstract, key words, and references. In addition, we underline the importance of carefully reading and following general recommendations for the conduct, reporting, editing, and publication of scholarly papers. Specific guidelines are reviewed for improving clarity, accuracy, and transparency, from protocol registration and ethical approval to submission issues, inclusive of rehabilitation specificities. A thorough review of the mission and instructions of the journals under consideration is also critical, inclusive of manuscript preparation guidelines such as word limits of main text, limits in number and style of references, tables and figures, format, checklist, and other specific instructions. Finally, each and every sentence should be iteratively revised for grammar, style, and clarity.

Responsiveness and minimal important change of the Pain Catastrophizing Scale in people with chronic low back pain undergoing multidisciplinary rehabilitation.

BACKGROUND: The Pain Catastrophizing Scale (PCS), a widely used tool to assess catastrophizing related to spinal disorders, shows valid psychometric properties in general but the minimal important change (MIC) is still not determined. AIM: The aim of this study was to assess responsiveness and MIC of the PCS in individuals with chronic low back pain (LBP) undergoing multidisciplinary rehabilitation. DESIGN: Prospective observational study. SETTING: The setting was outpatient rehabilitation hospital. POPULATION: Two hundred and five patients with chronic LBP. METHODS: Before and after an 8-week multidisciplinary rehabilitation program, 205 patients completed the Italian version of the PCS (PCS-I). We calculated the PCS-I responsiveness by distribution-based methods (effect size [ES], standardized response mean [SRM], and minimum detectable change [MDC]) and anchor-based methods [receiver operating characteristic (ROC) curves]. After the program, participants completed a 7-point global perceived effect scale (GPE), based on which they were classified as "improved" vs. "stable." ROC curves computed the best cut-off level (taken as the MIC) between the two groups. ROC analysis was also performed on subgroups according to patients' baseline PCS scores. RESULTS: ES, SRM and MDC were 0.71, 0.67 and 7.73, respectively. ROC analysis yielded an MIC of 8 points (95% confidence interval [CI]: 6-10; area under the curve [AUC]: 0.88). ROC analysis of the PCS subgroups confirmed an MIC of 8 points (95%CI: 6-10) for no/low catastrophizers (score <30, N.=159; AUC: 0.90) and indicated an MIC of 11 points (95%CI: 8-14) for catastrophizers (score >30, N.=33; AUC: 0.84). CONCLUSIONS: The PCS-I showed good ability to detect patient-perceived clinical changes in chronic LBP postrehabilitation. The MIC values we determined provide a benchmark for assessing individual improvement in this clinical context. CLINICAL REHABILITATION IMPACT: The present study calculated - in a sample of people with chronic LBP - the responsiveness and MIC of the PCS. These values increase confidence in interpreting score changes, enhancing their meaningfulness for both research and clinical contexts.

Facial Disability Index in Adults With Peripheral Facial Palsy: Rasch Analysis and Suggestions for Refinement.

OBJECTIVE: To investigate the psychometric properties of the validated Italian version of the Facial Disability Index (FDI), a patient-reported outcome measure widely used to assess individuals with peripheral facial palsy. DESIGN: Methodological research on cross-sectional data from a convenience sample. SETTING: Outpatient university rehabilitation clinic. PARTICIPANTS: A total of 168 (N=168) outpatients (66% female; mean age, 44±15 years) with peripheral facial palsy of diverse etiology (48% postsurgical, 31% Bell palsy, 8% posttraumatic, 3% congenital, 11% other medical conditions) and severity at the first visit. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The 2 FDI subscales, physical function (FDI-PHY) and social/well-being function (FDI-SWB), were separately analyzed using classical test theory methods and Rasch analysis. RESULTS: Cronbach α was 0.79 in FDI-PHY and 0.74 in FDI-SWB, while item-rest correlation ranged from 0.36-0.67 in FDI-PHY and from 0.43-0.68 in FDI-SWB. In the FDI-PHY, we deleted 2 underused response categories, rescoring the remaining ones. In the FDI-SWB, some response categories did not function as expected by the Rasch model: their collapse into a 4-level format solved this problem. In each subscale, all items fitted the Rasch model except item 4 (eye tearing/becoming dry) in FDI-PHY that showed an unexpectedly high response variability. The person separation reliability of both subscales indicated that they are useful only for group-level judgments. In both subscales, principal component analysis of the residuals showed unidimensionality and absence of locally dependent items. No significant differential item functioning concerning sex, age, or time from paralysis emerged. CONCLUSIONS: Our study demonstrated overall positive psychometric characteristics of FDI except for the functioning of the response categories. We propose a refined version with 4 response categories only and related conversion graphs that may improve the interpretability, feasibility, and metric performance of this tool.

Diagnosing sarcopenia: Functional perspectives and a new algorithm from the ISarcoPRM.

Sarcopenia is an important public health problem, characterized by age-related loss of muscle mass and muscle function. It is a precursor of physical frailty, mobility limitation, and premature death. Muscle loss is mainly due to the loss of type II muscle fibres, and progressive loss of motor neurones is thought to be the primary underlying factor. Anterior thigh muscles undergo atrophy earlier, and the loss of anterior thigh muscle function may therefore be an antecedent finding. The aim of this review is to provide an in-depth (and holistic) neuromusculoskeletal approach to sarcopenia. In addition, under the umbrella of the International Society of Physical and Rehabilitation Medicine (ISPRM), a novel diagnostic algorithm is proposed, developed with the consensus of experts in the special interest group on sarcopenia (ISarcoPRM). The advantages of this algorithm over the others are: special caution concerning disorders related to the renin-angiotensin system at the case finding stage; emphasis on anterior thigh muscle mass and function loss; incorporation of ultrasound for the first time to measure the anterior thigh muscle; and addition of a chair stand test as a power/performance test to assess anterior thigh muscle function. Refining and testing the algorithm remains a priority for future research.

Rasch validation and comparison of the German versions of the Locomotor Capabilities Index-5 and Prosthetic Mobility Questionnaire 2.0 in lower-limb prosthesis users.

This study aimed to compare, through Rasch analysis, the psychometric properties of the Locomotor Capabilities Index (LCI-5) and Prosthetic Mobility Questionnaire (PMQ 2.0) in German lower-limb prosthesis users. The questionnaires were concurrently administered to a convenience sample of 98 consecutively recruited individuals with lower limb amputation (LLA) (male/female = 61/37; mean age 57 ± 14 years). LCI-5 showed disordered rating scale thresholds (one response option in three items required collapsing); local dependence between two items (resolved by creating a testlet); underfit of one item ('Get up from the floor'); and presence of a second weak dimension. PMQ 2.0 showed a correctly functioning rating scale; good fit of the data to the model (apart from some overfit); local dependence between two items (absorbed by creating a testlet); and essential unidimensionality. At scale co-calibration onto a common interval-scaled metric, PMQ 2.0 was better targeted than LCI-5 (i.e. the extent of item difficulty was more appropriate for the sample) and its operational range allowed a more precise measurement of higher locomotor abilities. The correlation between LCI-5 and PMQ 2.0 scores was rho = 0.78. In conclusion, LCI-5 revealed some drawbacks, confirming a previous Rasch study; refinement of its rating scale and item selection seems therefore warranted. The PMQ 2.0 demonstrated good overall measurement quality, in line with previous Italian and Slovene studies. The operational range of the PMQ 2.0 makes it more suitable than LCI-5 for assessing people with high locomotor abilities.

Cross-cultural adaptation, reliability and validity of the Fremantle Knee Awareness Questionnaire in Italian subjects with painful knee osteoarthritis.

BACKGROUND AND AIM: Growing attention is being given to utilising physical function measures to better understand and manage knee osteoarthritis (OA). The Fremantle Knee Awareness Questionnaire (FreKAQ), a self-reported measure of body-perception specific to the knee, has never been validated in Italian patients. The aims of this study were to culturally adapt and validate the Italian version of the FreKAQ (FreKAQ-I), to allow for its use with Italian-speaking patients with painful knee OA. METHODS: The FreKAQ-I was developed by means of forward-backward translation, a final review by an expert committee and a test of the pre-final version to evaluate its comprehensibility. The psychometric testing included: internal structural validity by Rasch analysis; construct validity by assessing hypotheses of FreKAQ correlations with the knee injury and osteoarthritis outcome score (KOOS), a pain intensity numerical rating scale (PI-NRS), the pain catastrophising scale (PCS), and the Hospital anxiety and depression score (HADS) (Pearson's correlations); known-group validity by evaluating the ability of FreKAQ scores to discriminate between two groups of participants with different clinical profiles (Mann-Whitney U test); reliability by internal consistency (Cronbach's alpha) and test-retest reliability (intraclass correlation coefficient, ICC2.1); and measurement error by calculating the minimum detectable change (MDC). RESULTS: It took one month to develop a consensus-based version of the FreKAQ-I. The questionnaire was administered to 102 subjects with painful knee OA and was well accepted. Internal structural validity confirmed the substantial unidimensionality of the FreKAQ-I: variance explained was 53.3%, the unexplained variance in the first contrast showed an eigenvalue of 1.8, and no local dependence was detected. Construct validity was good as all of the hypotheses were met; correlations: KOOS (rho = 0.38-0.51), PI-NRS (rho = 0.35-0.37), PCS (rho = 0.47) and HADS (Anxiety rho = 0.36; Depression rho = 0.43). Regarding known-groups validity, FreKAQ scores were significantly different between groups of participants demonstrating high and low levels of pain intensity, pain catastrophising, anxiety, depression and the four KOOS subscales (p ≤ 0.004). Internal consistency was acceptable (α = 0.74) and test-retest reliability was excellent (ICC = 0.92, CI 0.87-0.94). The MDC95 was 5.22 scale points. CONCLUSION: The FreKAQ-I is unidimensional, reliable and valid in Italian patients with painful knee OA. Its use is recommended for clinical and research purposes.

Construct validity of the Quebec Back Pain Disability Scale: a factor analytic and Rasch study.

BACKGROUND: Studies on structural validity of the Quebec Back Pain Disability Scale (QBPDS) showed uncertain unidimensionality. AIM: The aim of this study was to investigate dimensionality and internal construct validity of the QBPDS, using advanced psychometric methods. DESIGN: The design of this study is a secondary analysis of data from a cross-sectional observational study. SETTING: The setting was an outpatient rehabilitation hospital. POPULATION: Analyzed subjects consisted of 201 patients with chronic low back pain (40% men; mean age 48±12 years). METHODS: Confirmatory (CFA) and then Exploratory Factor Analysis (EFA), and Rasch analysis were used. RESULTS: CFA could not provide a satisfactory one-factor solution. Thus, according to a preliminary parallel analysis, two factor structures were examined: 1) a single-factor solution, that showed good model fit according to Goodness of Fit Index and Comparative Fit Index, acceptable fit according to Root Mean Square Error of Approximation, and poor fit according to Standardized Root Mean Square of Residuals; and 2) a bi-factor solution, both showing a good fit in all 4 indices. The Explained Common Variance Index was 0.87. Thus, it was considered appropriate to apply Rasch analysis to our QBPDS data. Four items underfit the Rasch model and showed (two by two) local dependency. Removing these 4 misfitting items resulted in an acceptable fit to the Rasch model of the 16 remaining items. CONCLUSIONS: All results pointed towards an essential unidimensionality of the QBPDS. Thus, we suggest to provisionally use the full QBPDS and its global score, pending further research on scale's construct validity. If the suboptimal performance of 4 items would be confirmed, the deletion of some of them could improve the metric quality of the scale. CLINICAL REHABILITATION IMPACT: This study fills an evidence gap on important measurement properties of the QBPDS (namely, dimensionality and internal construct validity), thus representing a useful step towards the definition of the more suitable outcome measures for research and clinical practice in nonspecific chronic LBP.

Scale Shortening and Decrease in Measurement Precision: Analysis of the Pain Self-Efficacy Questionnaire and Its Short Forms in an Italian-Speaking Population With Neck Pain Disorders.

OBJECTIVE: Short (2- and 4-item) forms of the Pain Self-Efficacy Questionnaire (PSEQ) have been proposed, but their measurement precision at the individual level is unclear.The purpose of this study was to analyze the Rasch psychometric characteristics of PSEQ and its 3 short forms (one 4-item and two 2-item versions) in an Italian-speaking population with neck pain (NP) disorders and compare their measurement precision at the individual level through calculation of the test information function (TIF). METHODS: Secondary analysis of data from a prospective single-group observational study was conducted. In 161 consecutive participants (mean age = 45 years [SD = 14]; 104 women) with NP disorders, a Rasch analysis was performed on each version of the PSEQ (full scale plus 3 short forms), and the TIF was calculated to examine the degree of measurement precision in estimating person ability over the whole measured construct (pain self-efficacy). RESULTS: In all versions of the PSEQ, the rating scale fulfilled the category functioning criteria, and all items showed an adequate fit to the Rasch model. The TIF showed a bell-shaped distribution of information, with an acceptable measurement precision (standard error <0.5) for persons with a wide range of ability; conversely, measurement precision was unacceptably low in each short form (particularly the two 2-item versions). CONCLUSIONS: The results confirm and expand reports on the sound psychometric characteristics of PSEQ, showing for the first time, to our knowledge, its conditional precision in estimating pain self-efficacy measures in Italian individuals with NP disorders. The study cautions against use of the 3 PSEQ short forms for individual-level clinical decision-making. IMPACT: Short scales are popular in rehabilitation settings largely because they can save assessment time and related costs. The psychometric characteristics of the 10-item PSEQ were confirmed and deepened, including its precision in estimating individual pain self-efficacy at different levels of this latent variable. On the other hand, low measurement precision of the 3 PSEQ short forms cautions against their use for individual judgments.