RESUMEN
INTRODUCTION: The paediatric Haemophilia Activities List (pedHAL) was developed to measure activities and participation in children and youth with haemophilia. Results from international studies provide an opportunity to determine which items are universally important. AIM: The aim of this study was to determine which items of the pedHAL are redundant to construct a shorter version of the pedHAL. METHODS: This study is a cross-sectional multicentre secondary analysis on pooled data of published studies using the pedHAL (7 domains, 53 items, optimum score: 100) in children with haemophilia A/B aged 4-18 years. To identify redundant items, the following aspects were evaluated: floor and ceiling effects, proportions of missing and 'not applicable' responses, inter-item correlations, component loadings in an exploratory factor analysis, internal consistency and item-total correlations. RESULTS: Data on 315 patients with haemophilia from 6 studies were evaluated. Median age was 12.2 years) (range 4.0-18.0), 87.3% had severe haemophilia and 80.3% received prophylaxis. Median (IQR) pedHAL sum score was 96.7 (88.0-100). After a stepwise procedure, 31 items were removed, resulting in a pedHALshort of 22 items, representing all original 7 domains. Most remaining items belonged to the domains 'sitting/kneeling/standing' and 'functions of the legs'. The pedHALshort sum score was similar to the original pedHAL sum score, with small differences in 5 domains. CONCLUSION: This clinimetric study resulted in >50% reduction of the length of the pedHAL. The 22-item pedHALshort reduces patient burden and is expected to capture the information on activities and participation. The pedHALshort needs validation in other populations.