Measurement Properties of the Patient-Specific Functional Scale and Its Current Uses: An Updated Systematic Review of 57 Studies Using COSMIN Guidelines

Chinese version of the Physical Resilience Scale (PRS): reliability and validity test based on Rasch analysis

BACKGROUND

Physical resilience is known to minimize the adverse outcomes of health stressors for older people. However, validated instruments that assess physical resilience in older adults are rare. Therefore, the purpose of this study was to translate the Physical Resilience Scale (PRS) into Chinese and to validate its psychometric properties in a population of community-dwelling older adults following SARS-CoV-2 infection.

METHODS

This study used a cross-sectional design and translated the Physical Resilience Scale into Chinese. A total of 426 older adults who had recovered from SARS-CoV-2 infection were chosen for assessment through convenience sampling. The measurement data were analyzed using the Rasch analysis.

RESULTS

Rasch analysis indicates that the Physical Resilience Scale demonstrates excellent reliability, validity, and unidimensionality. The Infit MNSQ and Outfit MNSQ of each entry were 0.77 ~ 1.19, and the degree of fit of each entry to the scale was good. Person and item separation reliability support the internal consistency of the studied samples and PRS items.

CONCLUSIONS

The Physical Resilience Scale has good reliability and is suitable for the assessment of physical resilience tests in older people. However, the overall difficulty of the scale is not suitable for older adults of all ability ranges, and it is possible to add higher and lower difficulty items and adjust the difficulty spacing between items in a later study.

Psychometric properties of patient-reported outcome measures assessing recovery from hand fractures: a systematic review

PURPOSE

To extensively review Patient Reported Outcome Measures (PROMs) used to assess outcomes in persons with hand fractures in terms of their psychometric properties.

METHODS

A COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodological review was conducted. Six electronic databases were searched (Medline, Embase, Scopus, Web of Science, PsycINFO, CINAHL) for studies evaluating the psychometric properties of PROMs assessing recovery from hand fracture. Titles and abstracts, full text review, quality assessment and data extraction were performed by two reviewers. Any disagreements were resolved after review by a third, expert reviewer. Quality assessment of included studies was performed using the COSMIN checklist.

RESULTS

This COSMIN review found that there were only 4 studies that fulfilled the inclusion criteria in terms of assessing measurement properties of PROMs in hand fractures. Only the construct validity of the Disabilities of the Arm, Shoulder, and Hand (DASH), the Quick DASH (QDASH) and the Duruoz Hand Index (DHI), and the responsiveness of the DASH, the Patient Specific Functional Scale (PSFS), the Patient-Rated Wrist and Hand Evaluation (PRWHE) and the Michigan Hand Outcomes Questionnaire (MHQ) were assessed in these studies. The overall rating of the studies was assessed as insufficient or indeterminate and quality of evidence was assessed as moderate, low, or very low by our team.

CONCLUSIONS

This study identified that there is a lack of evidence in the medical literature with regards to the measurement properties of PROMs in patients with hand fractures. The 4 included studies do not provide good quality data to support the use of these PROMS in patients with hand fractures. There is a need for more studies for more PROMs. This has important consequences for how outcomes will be measured in clinical studies in hand research and in clinical practice.

Brain and muscles magnetic stimulation in a drug-free case of Parkinson's disease: Motor improvements concomitant to neuroplasticty

Noninvasive stimulation of the nervous system is of growing interest in Parkinson's disease (PD) to slow-down motor decline and decrease medication and its side-effects. Repetitive transcranial magnetic stimulation (rTMS) used in PD to modulate the excitability of the primary motor cortex (M1) provided controversial results, in part because of interactions with medication. This warrants to administer rTMS in drug-free patients. Repetitive peripheral magnetic stimulation (rPMS of muscles) has not yet been tested in PD. Its influence on M1 plasticity (as tested by TMS, transcranial magnetic stimulation) and sensorimotor disorders in other health conditions makes it worth be explored in PD. Thus, rTMS and rPMS were tested in a drug-free woman (52 years old, PD-diagnosed 10 years ago) in four different rTMS + rPMS combinations (one week apart): sham-sham, real-real, real-sham, sham-real. rTMS was applied over M1 contralateral to the most impaired bodyside, and rPMS on muscles of the legs, trunk, and arms, bilaterally. M1 plasticity (TMS measures) and motor symptoms and function (clinical outcomes) were measured at different timepoints. The real-real session induced the largest motor improvements, with possible summation of effects between sessions, and maintenance at follow-up (80 days later). This was paralleled by changes of M1 facilitation and inhibition. This sheds a new light on the link between TMS measures of M1 plasticity and motor changes in PD and informs on the remaining potential for neuroplasticity and functional improvement after 10 years of PD with no antiparkinsonian drug. De novo patients with PD (drug-free) should be motivated to participate in future randomized clinical trials to further test the slow-down or delay of motor decline under noninvasive neurostimulation regimens, whatever the stage of the disease.

Restoration of normal central pain processing following manual therapy in nonspecific chronic neck pain

OBJECTIVE

To determine if a 4-week manual therapy treatment restores normal functioning of central pain processing mechanisms in non-specific chronic neck pain (NSCNP), as well as the existence of a possible relationship between changes in pain processing mechanisms and clinical outcome.

DESIGN

Cohort study.

METHODS

Sixty-three patients with NSCNP, comprising 79% female, with a mean age of 45.8 years (standard deviation: 14.3), received four treatment sessions (once a week) of manual therapy including articular passive mobilizations, soft tissue mobilization and trigger point treatment. Pressure pain thresholds (PPTs), conditioned pain modulation (CPM) and temporal summation of pain (TSP) were evaluated at baseline and after treatment completion. Therapy outcome was measured using the Global Rating of Change Scale (GROC), the Neck disability Index (NDI), intensity of pain during the last 24 hours, Tampa Scale of Kinesiophobia (TSK) and Pain Catastrophizing Scale (PCS). Two sets of generalized linear mixed models with Gaussian response and the identity link were employed to evaluate the effect of the intervention on clinical, psychological and psychophysical measures and the association between psychophysical and clinical outcomes.

RESULTS

Following treatment, an increased CPM response (Coefficient: 0.89; 95% credibility interval = 0.14 to 1.65; P = .99) and attenuated TSP (Coefficient: -0.63; 95% credibility interval = -0.82 to -0.43; P = 1.00) were found, along with amelioration of pain and improved clinical status. PPTs at trapezius muscle on the side of neck pain were increased after therapy (Coefficient: 0.22; 95% credibility interval = 0.03 to 0.42; P = .98), but not those on the contralateral trapezius and tibialis anterior muscles. Only minor associations were found between normalization of TSP/CPM and measures of clinical outcome.

CONCLUSION

Clinical improvement after manual therapy is accompanied by restoration of CPM and TSP responses to normal levels in NSCNP patients. The existence of only minor associations between changes in central pain processing and clinical outcome suggests multiple mechanisms of action of manual therapy in NSCNP.

Cross-cultural adaptation and psychometric properties of the Italian version of the Patient-Specific Functional Scale (PSFS) in subjects with shoulder pain

PURPOSE

To cross-culturally adapt the Patient-Specific Functional Scale (PSFS) into Italian and study its classic psychometric properties in subjects with shoulder pain (SP).

MATERIALS AND METHODS

The PSFS was translated into Italian and administered to 109 SP subjects. Acceptability (time to administer, floor and ceiling effects), reliability (internal consistency [Cronbach's alpha], test-retest reliability [Intraclass Correlation Coefficient (ICC)], and measurement error [Standard Error of Measurement (SEM), Minimal Detectable Change, (MDC)]), were assessed. Moreover, construct validity was investigated through a-priori hypothesis testing, comparing the PSFS with the Disability of the Shoulder, Arm and Hand (DASH) scale, 36-item Short Form Health Survey (SF-36) and Numeric Pain Rating scale (NPRS).

RESULTS

The PSFS was successfully adapted into Italian, and its acceptability was satisfied. Internal consistency was high (Cronbach's alpha = 0.925), and test-retest reliability was good (ICC = 0.866, 95% CI = 0.749-0.931). A SEM of 0.7 points and an MDC of 1.9 points were obtained. We observed moderate evidence for construct validity, with 4/6 correlations between other measures being respected.

CONCLUSION

This study provided reliability and validity of the PSFS in a sample of Italian SP subjects. Future studies should assess the responsiveness of using the PSFS as an outcome measure to capture clinical changes after treatment.

Self-Efficacy in Nepali Adults With Musculoskeletal Pain: Measurement Properties of Hard-Copy and Online Versions of the Pain Self-Efficacy Questionnaire

The Pain Self-Efficacy Questionnaire (PSEQ) is commonly used in pain self-efficacy research. Yet its Nepali translation is unavailable, limiting the ability to conduct cross-cultural research on the role of self-efficacy in musculoskeletal pain and its management. This study aimed to 1) translate and culturally adapt the 10-item (PSEQ-10) and 2-item (PSEQ-2) versions of the PSEQ into Nepali, 2) evaluate their measurement properties in Nepali adults with musculoskeletal pain, and 3) evaluate whether the type of administration (ie, hard-copy vs online) affected their measurement properties. The measurement properties of different administrations of the Nepali PSEQ-10 and PSEQ-2 were evaluated in 180 Nepali adults (120 hard-copy and 60 online administrations) with musculoskeletal pain. We conducted confirmatory factor analyses and estimated the measures' internal consistencies, test-retest reliabilities, and smallest detectable changes using standard error of measurement. We planned to conclude that the measures were valid if ≥ 75% of the validity hypotheses were supported. The results supported unidimensionality for the Nepali PSEQ-10. The Nepali PSEQ-2 and PSEQ-10 evidenced excellent internal consistencies (Cronbach alphas = .90-.95) and good to excellent test-retest reliabilities (intraclass correlation coefficient = .61-.85) for both administrations. Construct validity (r's ≥ .20) and concurrent validity (r's ≥ .83) were supported, as hypothesized. Both hard-copy and online administrations of the Nepali PSEQ-2 and PSEQ-10 are similar, reliable, and valid ways to assess self-efficacy in Nepali adults with musculoskeletal pain. The findings should facilitate telehealth and cross-cultural research on pain self-efficacy in Nepal. PERSPECTIVE: This is the first Nepali adaptation of a self-efficacy scale with testing of measurement properties for hard-copy and online administrations. It will facilitate the assessment of pain self-efficacy in clinical practice and research and facilitate a deeper cross-cultural understanding of the role of self-efficacy in musculoskeletal pain.

Effectiveness comparison of genicular nerve ablation for knee osteoarthritic versus post-total knee arthroplasty pain

Background

Genicular nerve radiofrequency ablation (GNRFA) is a popular and effective procedure to treat arthritic knee pain. For refractory arthritic pain that fails conservative treatment, total knee arthroplasty (TKA) has been an excellent option. Unfortunately, 15-30% of people who undergo a TKA continue to experience pain and stiffness in the knee. The treatment options for post-TKA knee pain are limited. Pain providers have been trialing GNRFA on this pain condition. However, convincing evidence of its efficacy in treating post-TKA pain is still lacking.

Methods

This is a retrospective study of 73 patients who had undergone genicular nerve RFA, 46 (63.01%) with osteoarthritic pain, and 27 (36.99%) with post-TKA pain. We compared the outcomes (pain relief, function, and complications) between these two groups at 3 months and 6 months after RFA.

Results

Before RFA, there was no significant difference in initial pain and functional level between these two groups. After RFA, the two groups had comparable pain relief at 3 months (p = 0.68) and 6 months (p = 0.53), and similar functionality at 3 months (p = 0.36) and 6 months (p = 0.65).The overall success rate (≥50% pain relief after RFA) was 80.82%, 95% CI: 70.34%-88.22% (osteoarthritic group 80.43%, 95% CI: 66.83%-89.35%, post-TKA 81.48%, 95% CI: 63.30%-91.82%, P = 0.91) at 3-month follow-up and 56.16%, 95% CI: 44.76%-66.95% (osteoarthritic group 56.52%, 95% CI: 42.25%-69.79%, post-TKA 55.56%, 95% CI: 37.31%-72.41%, P = 0.94) at 6-month follow-up.There were no reported complications in either group.

Conclusions

Genicular Nerve Radiofrequency Ablation (GNRFA) holds the potential to be equally effective for both post-TKA knee pain and osteoarthritic knee pain.

RECITAL: a non-inferiority randomised control trial evaluating a virtual fracture clinic compared with in-person care for people with simple fractures (study protocol)

INTRODUCTION

Most simple undisplaced fractures can be managed without surgery by immobilising the limb with a splint, prescribing medication for pain, and providing advice and early rehabilitation. Recent systematic reviews based on retrospective observational studies have reported that virtual fracture clinics can deliver follow-up care that is safe and cost-effective. However, no randomised controlled trial has investigated if a virtual fracture clinic can provide non-inferior physical function outcomes compared with an in-person clinic for patients with simple fractures.

METHODS AND ANALYSIS

312 participants will be recruited from 2 metropolitan hospitals located in Sydney, Australia. Adult patients will be eligible if they have an acute simple fracture that can be managed with a removable splint and is deemed appropriate for follow-up at either the virtual or in-person fracture clinic by an orthopaedic doctor. Patients will not be eligible if they have a complex fracture that requires a cast or surgery. Eligible participants will be randomised to receive their follow-up care either at the virtual or the in-person fracture clinic. Participants at the virtual fracture clinic will be reviewed within 5 days of receiving a referral through video calls with a physiotherapist. Participants at the in-person fracture clinic will be reviewed by an orthopaedic doctor within 7-10 days of receiving a referral. The primary outcome will be the patient's function measured using the Patient-Specific Functional Scale at 12 weeks. Secondary outcomes will include health-related quality of life, patient-reported experiences, pain, health cost, healthcare utilisation, medication use, adverse events, emergency department representations and surgery.

ETHICS AND DISSEMINATION

The study has been approved by the Sydney Local Health District Ethics Review Committee (RPAH Zone) (X23-0200 and 2023/ETH01038). The trial results will be submitted for publication in a reputable international journal and will be presented at professional conferences.

TRIAL REGISTRATION NUMBER

ACTRN12623000934640.

Study protocol for the validation of a new pictorial functional scale in patients with knee osteoarthritis: the functional activity scoring tool (FAST)

BACKGROUND

Patient-reported outcome measures (PROMs) are required for patient-centred care. There are limited PROMs with good psychometric properties, and limitations to any language-based scale are often constrained by the written words or numerals used. Therefore, we developed the Functional Activity Scoring Tool (FAST), a self-reporting pictorial scale. FAST measures the impact of knee osteoarthritis on essential activities of daily living (ADL) and the significant changes in the self-perceived functional status over time.

OBJECTIVES

This study aims to (1) develop FAST with adaptation from the Wong-Baker FACES pain rating scale, (2) validate FAST against the Patient-Specific Functional Scale (PSFS) and Knee Injury and Osteoarthritis Outcome Score (KOOS) and (3) establish the reliability, validity and responsiveness of FAST in individuals with knee osteoarthritis.

METHODS AND ANALYSIS

The prospective study protocol investigates the validity, responsiveness and reliability of FAST. The PSFS and KOOS will be gold standard comparisons. Participant recruitment will occur at four public polyclinics that offer physiotherapy outpatient services in Singapore. Onsite physiotherapists familiar with the study eligibilities will refer potential participants to the investigators after the routine physiotherapy assessment. After providing written consent, eligible participants will complete outcome measurements with FAST, the PSFS and KOOS during baseline and follow-up assessments. The Global Rating of Change (GROC) scale will determine how the participant's knee status was changed compared with the beginning of the physiotherapy intervention.

ETHICS AND DISSEMINATION

SingHealth Centralised Institutional Review Board approved the study (CIRB reference number: 2022/2602). The final results will be published via scientific publication. FAST will benefit the evaluation and management of those who suffer knee osteoarthritis regardless of English proficiency or language barriers.

TRIAL REGISTRATION NUMBER

NCT05590663.

Reliability, Measurement Error, Responsiveness, and Minimal Important Change of the Patient-Specific Functional Scale 2.0 for Patients With Nonspecific Neck Pain

OBJECTIVE

The Patient-Specific Functional Scale (PSFS) is a patient-reported outcome measure used to assess functional limitations. Recently, the PSFS 2.0 was proposed; this instrument includes an inverse numeric rating scale and an additional list of activities that patients can choose. The aim of this study was to assess the test-retest reliability, measurement error, responsiveness, and minimal important change of the PSFS 2.0 when used by patients with nonspecific neck pain.

METHODS

Patients with nonspecific neck pain completed a numeric rating scale, the PSFS 2.0, and the Neck Disability Index at baseline and again after 12 weeks. The Global Perceived Effect (GPE) was also collected at 12 weeks and used as an anchor. Test-retest measurement was assessed by completion of a second PSFS 2.0 after 1 week. Measurement error was calculated using a Bland-Altman plot. The receiver operating characteristic method with the anchor (GPE) functions as the reference standard was used for calculating the minimal important change.

RESULTS

One hundred patients were included, with 5 lost at follow-up. No floor and ceiling effects were reported. In the test-retest analysis, the mean difference was 0.15 (4.70 at first test and 4.50 at second test). The ICC (mixed models) was 0.95, indicating high agreement (95% CI = 0.92-0.97). For measurement error, the upper and lower limits of agreement were 0.95 and -1.25 points, respectively, with a smallest detectable change of 1.10. The minimal important change was determined to be 2.67 points. The PSFS 2.0 showed satisfactory responsiveness, with an area under the curve of 0.82 (95% CI = 0.70-0.93). There were substantial to high correlations between the change scores of the PSFS 2.0 and the Neck Disability Index and GPE (0.60 and 0.52, respectively; P < .001).

CONCLUSION

The PSFS 2.0 is a reliable and responsive patient-reported outcome measure for use by patients with neck pain.

An Exploration of Physical Therapy Outcomes and Psychometric Properties of the Patient-Specific Functional Scale After an Interdisciplinary Pain Management Program

OBJECTIVES

The Patient-Specific Functional Scale (PSFS) has been used to assess physical functioning in various chronic pain populations. There is a lack of evidence for its use with diverse pain populations who have high-impact chronic pain (HICP). The primary aim of this study was to assess the psychometric properties of the PSFS with a heterogeneous sample of patients with HICP.

MATERIALS AND METHODS

A retrospective observational study of prospective functional outcomes collected before and after participation in an intensive pain management program: PSFS, Disabilities of the Arm, Shoulder, and Hand, Lower Extremity Functional Scale, Neck Disability Index, Oswestry Disability Index, multidimensional patient impression of change, pain intensity, pain limitation, and fear-avoidance from the charts of 509 intensive pain management program completers. The reliability, validity, and responsiveness of the PSFS were analyzed using Cronbach α, Pearson correlations, and receiver operating characteristics.

RESULTS

Statistically significant improvements were found for all outcomes after program participation (all P < 0.0001). Correlations of the PSFS with similar outcomes (convergent validity) were lower than expected ( r = 0.16 to 0.33). A low correlation ( r = -0.12) with an unrelated measure, fear avoidance, supported divergent validity. PSFS change score correlations with similar outcome measures ranged from 0.46 to 0.53. The area under the curve values for the PSFS ranged from 0.801 to 0.857, suggesting a moderate ability for the PSFS to detect improvement.

DISCUSSION

The psychometric properties of the PSFS showed mixed support for construct validity but good support for the responsiveness of the PSFS when used with a heterogeneous sample of patients with HICP.

Reliability, Validity, and Responsiveness of the Patient-Specific Functional Scale for Measuring Mobility-Related Goals in People With Multiple Sclerosis

BACKGROUND AND PURPOSE

This study's purpose was to investigate the reliability, validity, and responsiveness of the Patient-Specific Functional Scale (PSFS) for measuring mobility-related goals in people with multiple sclerosis (MS).

METHODS

Data from 32 participants with MS who underwent 8 to 10 weeks of rehabilitation were analyzed (Expanded Disability Status Scale scores 1.0-7.0). For the PSFS, participants identified 3 mobility-related areas where they had difficulty and rated them at baseline, 10 to 14 days later (before starting intervention), and immediately after intervention. Test-retest reliability and response stability of the PSFS were calculated using the intraclass correlation coefficient (ICC 2,1 ) and minimal detectable change (MDC 95 ), respectively. Concurrent validity of the PSFS was determined with the 12-item Multiple Sclerosis Walking Scale (MSWS-12) and the Timed 25-Foot Walk Test (T25FW). PSFS responsiveness was determined using Cohen's d , and minimal clinically important difference (MCID) was calculated based on patient-reported improvements on a Global Rating of Change (GRoC) scale.

RESULTS

The PSFS total score demonstrated moderate reliability (ICC 2,1 = 0.70, 95% CI: 0.46 to 0.84) and the MDC was 2.1 points. At baseline, the PSFS was fairly and significantly correlated with the MSWS-12 ( r = -0.46, P = 0.008) but not with the T25FW. Changes in the PSFS were moderately and significantly correlated with the GRoC scale (ρ = 0.63, P < 0.001), but not with MSWS-12 or T25FW changes. The PSFS was responsive ( d = 1.7), and the MCID was 2.5 points or more to identify patient-perceived improvements based on the GRoC scale (sensitivity = 0.85, specificity = 0.76).

DISCUSSION AND CONCLUSIONS

This study supports the use of the PSFS as an outcome measure in people with MS to assess mobility-related goals.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A423 ).

Measurement Property Evaluation of the Arabic Version of the Patient-Specific Functional Scale for Patients with Stroke

Neurological disorders refer to disorders that occur due to disease or damage to the nervous system. Stroke is one of the most common neurological disorders in which individuals commonly present with motor and sensory deficits, leading to the limitations on the activities of daily life. Outcome measures are used to assess and monitor patients' condition change. The patient-specific functional scale (PSFS) is an outcome measure used to assess changes in performance levels in participants with a functional disability during daily activities. This study aimed to assess the reliability and validity of the Arabic version of the patient-specific functional scale (PSFS-Ar) in individuals with stroke. A longitudinal cohort study was used to examine the reliability and validity of the PSFS-Ar in patients with stroke. All participants completed the PSFS-Ar in addition to other outcome measures. Fifty-five individuals participated (fifty male, five female). The PSFS-Ar showed excellent test-retest reliability, with ICC2,1 = 0.96, p < 0.001. The SEM and MDC95 of the PSFS-Ar were 0.37 and 1.03, respectively. No floor and ceiling effect was observed in this study. Additionally, the construct validity of the PSFS-Ar showed 100% satisfaction with the pre-defined hypotheses. Since the number of female participants was very small in this study, the findings were established for male individuals with stroke. This study showed that the PSFS-Ar is a reliable and valid outcome measure for male individuals with stroke.

The safety and efficacy of genicular nerve radiofrequency ablation for pain in inferolateral quadrant of the knee

Background

Genicular nerve radiofrequency ablation (RFA) is an effective procedure to alleviate knee pain. This procedure has been proven to be safe, except in the inferior lateral quadrant (ILQ) due to its innervation being near the common fibular nerve (CFN). Given the complexity of this approach, pain physicians do not routinely perform RFA in the ILQ, leading to inadequate pain relief in this region.

Methods

This is a retrospective study of 54 patients who had undergone genicular nerve RFA. Thirty patients had genicular nerve RFA of the knee joint including the ILQ innervated by the inferolateral genicular and recurrent fibular nerves, while 24 patients had RFA of the knee joint without involvement of the ILQ. We compared the outcomes (pain relief, function, and complications) in the patients with and without ILQ RFA at 3 months and 6 months after RFA.

Results

There was no significant difference in initial pain and functional level before RFA between these two groups. After RFA, the two groups had comparable pain relief at 3 months (p ​= ​0.06) and 6 months (p ​= ​0.20), and similar functionality at 3 months (p ​= ​0.29) and 6 months (p ​= ​0.12). There were no reported complications after RFA with or without ILQ RFA.

Conclusions

RFA of the innervation to the ILQ of the knee is as safe and effective as all other anterior quadrants.

Measurement Properties' Evaluation of the Arabic Version of the Patient-Specific Functional Scale in Patients with Multiple Sclerosis

Purpose: The aim of this study was to assess the reliability and validity of the Arabic version of the patient-specific functional scale (PSFS-Ar) in patients with multiple sclerosis (MS) disorder. Materials and Methods: Reliability and validity were examined in patients with multiple sclerosis using a longitudinal cohort study design. One hundred (N = 100) patients with MS were recruited to examine the PSFS-Ar, test-retest reliability (using the interclass correlation coefficient model 2,1 (ICC_2,1)), construct validity (using the hypothesis testing method), and floor-ceiling effect. Results: A total of 100 participants completed the PSFS-Ar (34% male, 66% female). The PSFS-Ar showed an excellent test-retest reliability score (ICC_2,1 = 0.87; 95% confidence interval, 0.75-0.93). The SEM of the PSFS-Ar was 0.80, while the MDC₉₅ was 1.87, indicating an acceptable measurement error. The construct validity of the PSFS-Ar was 100% correlated with the predefined hypotheses. As hypothesized, the correlation analysis revealed positive correlations between the PSFS-Ar and the RAND-36 domains of physical functioning (0.5), role limitations due to physical health problems (0.37), energy/fatigue (0.35), and emotional well-being (0.19). There was no floor or ceiling effect in this study. Conclusions: The study results showed that the PSFS-Ar is a self-reported outcome measure that is useful for detecting specific functional difficulties in patients with multiple sclerosis. Patients are able to express and report a variety of functional limitations easily and effectively, as well as to measure their response to physical therapy. The PSFS-Ar is, therefore, recommended for use in Arabic-speaking countries for clinical practice and research for patients with multiple sclerosis.

Measurement Properties of the Patient-Specific Functional Scale in Rehabilitation for Patients With Stroke: A Prospective Observational Study

OBJECTIVE

This study investigated the validity, reliability, responsiveness, and interpretability of the Patient-Specific Functional Scale (PSFS) in subacute stroke rehabilitation to determine its suitability to measure patient-identified rehabilitation goals.

METHODS

A prospective observational study was designed according to the checklist from Consensus-Based Standards for Selecting Health Measurement Instruments. Seventy-one patients diagnosed with stroke were recruited in the subacute phase from a rehabilitation unit in Norway. The International Classification of Functioning, Disability and Health was used to assess the content validity. Assessment of construct validity was based on hypotheses for correlation of the PSFS and comparator measurements. We assessed reliability by calculating the Intraclass Correlation Coefficient (ICC) (3.1) and the standard error of measurement. The assessment of responsiveness was based on hypotheses for the correlation of change scores between the PSFS and the comparator measurements. A receiver operating characteristic analysis was conducted to assess responsiveness. The smallest detectable change and minimal important change were calculated.

RESULTS

Eighty percent of the PSFS items were classified as activities and participation in the International Classification of Functioning, Disability and Health, indicating satisfactory content validity. The reliability was satisfactory with an ICC of 0.81 (95% CI = 0.69-0.89). The standard error of measurement was 0.70 point, and the smallest detectable change was 1.94 points. Five of 7 hypotheses were confirmed for construct validity, and 5 of 6 were confirmed for responsiveness, indicating moderate construct validity and high responsiveness. Assessing responsiveness with a criterion approach resulted in an area under the curve of 0.74. A ceiling effect was identified for 25% of the participants 3 months after discharge. The minimal important change was estimated to be 1.58 points.

CONCLUSION

This study demonstrates satisfactory measurement properties for the PSFS in individuals undergoing inpatient stroke rehabilitation.

IMPACT

This study supports the use of the PSFS to document and monitor patient-identified rehabilitation goals in patients receiving subacute stroke rehabilitation when applied using a shared decision approach.