Rasch analysis of the 32-item motor function measure in ambulant patients with Duchenne muscular dystrophy.

OBJECTIVE: This study analyzed the 32-item Motor Function Measure in a cohort of ambulatory patients with Duchenne muscular dystrophy using Rasch measurement methods. DESIGN: This is a psychometric study. SETTING: Rehabilitation centre of a large public children's hospital in Shenzhen, China. PARTICIPANTS: Data from 176 genetically confirmed ambulant patients with Duchenne muscular dystrophy (mean age 7.3 years, SD 2.3 years, range 3.1-13.1 years) were analyzed. RESULTS: Rasch analyses supported the Motor Function Measure domain D1 as a reliable (person reliability = 0.88, person separation index = 2.71) and valid (acceptable targeting, little misfit, minimal category disordering) measure in ambulant patients with Duchenne muscular dystrophy. Remodelling the domain D1 by collapsing item 25 from 4 to 3 response categories addressed the problematic disordered thresholds, resulting in a rebuilt domain D1 with enhanced measurement properties. However, findings for domains D2 and D3 did not fulfil most Rasch model expectations. There were disordered thresholds for most items in domains D2 and D3, with low reliability coefficients, item mistargeting and misfit, and large ceiling effects. CONCLUSION: Rasch analyses confirmed that the Motor Function Measure domain D1 was reliable and valid and provided a unidimensional measure for motor function in ambulant Duchenne muscular dystrophy patients. Accuracy of measurement had been enhanced through remodelling, and a rebuilt domain D1 with category collapsing for item 25 was proposed. The analysis revealed multiple limitations of the domains D2 and D3 that certain essential psychometrics were poorly met and, therefore, should be used with caution in this patient group.

Chronic pain, psychological distress, and quality of life in males with Duchenne muscular dystrophy.

AIM: To describe chronic pain in Duchenne muscular dystrophy (DMD) from children's/adolescents' perspectives, explore patient variables associated with self-reported pain, and examine the relationship between chronic pain, psychological functioning, and health-related quality of life (HRQoL). METHOD: This observational study included a paediatric cohort (aged 8-18 years; median age 9 years 4 months) with DMD under multidisciplinary care (n = 45). Clinical data of the latest visit were extracted from the electronic health record and assessment of pain, psychological distress, and HRQoL were performed during the same visit. RESULTS: Thirty-two patients reported pain during the previous 4 weeks, and 18 reported persistent or recurrent chronic pain. Average pain intensity of chronic pain was mild, with regions of the legs (n = 12), lower back (n = 6), hips (n = 6), and shoulder (n = 6) most frequently affected. Older age, higher body mass index, being non-ambulatory, wheelchair dependency, and spinal deformities were contextual variables related to the presence of chronic pain. Furthermore, chronic pain was significantly associated with psychological distress and reduced HRQoL in paediatric patients with DMD. INTERPRETATION: Chronic pain in paediatric DMD is frequent and widespread, highlighting the need for pain to be addressed in the routine care of affected young people. Chronic pain may make a significant contribution to psychological distress and impaired HRQoL in paediatric patients with DMD. WHAT THIS PAPER ADDS: Chronic pain differs in aetiology, scope, and nature compared with acute pain in paediatric Duchenne muscular dystrophy (DMD). Older age, higher body mass index, being non-ambulatory, wheelchair dependency, and spinal deformities are important patient variables. Chronic pain is significantly associated with psychological distress and reduced health-related quality of life in paediatric DMD.

Responsiveness and Minimal Clinically Important Difference of the Chinese Version of the Motor Function Measure-32 in Children and Adolescents with Duchenne Muscular Dystrophy.

PURPOSE: This study aimed to examine the responsiveness and minimal clinically important difference of the Motor Function Measure 32-Chinese version (MFM 32-CN) in children and adolescents with Duchenne muscular dystrophy (DMD). METHODS: This observational, prospective cohort study assessed changes in motor function over 12 months using the MFM 32-CN in 108 pediatric patients with DMD. RESULTS: Moderate to high internal responsiveness was found for MFM total, D1, and D2 scores (SRM = 0.46-0.83). Sufficient external responsiveness was observed in all MFM scores, as determined by a good correlation with the Patient Global Impression of Change (PGIC) ratings (r = 0.54-0.72, p < .01). The estimated MCID values derived from different anchor-based methods ranged from 4.7 to 6.0, with a median of 5.0 points (%). CONCLUSION: The MFM 32-CN demonstrates sufficient internal and external responsiveness as a measure of motor function in children and adolescents with DMD. The present study established the MCID of MFM-32 in pediatric patients with DMD.

Effectiveness of exercise interventions for children with cerebral palsy: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: The results of previous research into exercise interventions for children with cerebral palsy are inconsistent. The aim of this study is to assess the effectiveness of such exercise interventions. DESIGN: Systematic review and meta-analysis. METHODS: Systematic searches of the PubMed, Embase and Cochrane Library databases for randomized controlled trials involving exercise interventions for children with cerebral palsy, from inception to January 2020, were performed. Pooled weighted mean differences (WMDs) with 95% confidence intervals (95% CI) for gross motor function, gait speed, and muscle strength were calculated using random-effects models. RESULTS: A final total of 27 trials, including 834 children with cerebral palsy, were selected for quantitative analysis. Exercise interventions had no significant effect on the level of gross motor function (WMD 1.19; 95% CI -1.07 to 3.46; p = 0.302). However, exercise interventions were associated with higher levels of gait speed (WMD 0.05; 95% CI 0.00-0.10; p = 0.032) and muscle strength (WMD 0.92; 95% CI 0.19-1.64; p = 0.013). CONCLUSION: These results suggest that exercise interventions may have beneficial effects on gait speed and muscle strength, but no significant effect on gross motor function in children with cerebral palsy.