The Pediatric Outcomes Data Collection Instrument for a Polish sample with juvenile idiopathic arthritis: psychometric properties of proxy version

AimThe aims of the study were to investigate the psychometric properties of the Pediatric Outcomes Data Collection Instrument (PODCI) for parents of children aged 2-10years, in a Polish sample of juvenile idiopathic arthritis and to compare the results from children with chronic arthritis to the results from a normative sample. MethodsThe sample consisted of the parents of 29 (72.5%) girls and 11 (27.5%) boys. The ages of the children ranged from 2 to 10years (mean 6.50, standard deviation [SD] 2.63). Disease course was classified as oligoarticular (n=26, 65%) and polyarticular (n=14, 35%). Parents who took part in the intrarater reliability study completed the Polish version of PODCI twice. The PODCI consists of the following subscales: Upper Extremity and Physical Function, Transfer and Mobility Tasks, Sports/Physical Functioning, Pain/Comfort, and Happiness. A Global Functioning Scale consists of the mean of the mean of items' values for the first four scales. ResultsThe mean standarized Global Functioning Scale was 81.79 (SD 13.45), whereas the mean normative Global Functioning Scale score equaled 33.65 (SD 18.19). Cronbach's alpha value of the Global Functioning Scale was excellent and equaled 0.81. The effect size concerning the Global Functioning Scale equaled 0.123. Test-retest reliability equaled 0.98, whereas intrarater reliability (intraclass correlation coefficient) equaled 0.99. ConclusionsThe translation and cross-cultural adaptation of the PODCI questionnaire provides a Polish equivalent to assess physical function in children with chronic arthritis.