A psychometric investigation of performance‐based and self‐report measures in a pediatric population with chronic pain: How well do these measures work?

Abstract Background Traditional rehabilitation measures, such as the Functional Independence Measure for Children (WeeFIM II), designed to measure the need for assistance and severity of disability in children with developmental disabilities, may not be an optimal indicator of physical function among pediatric patients with chronic pain undergoing rehabilitation. A better understanding of the ability of physical outcome measures to detect change over time would improve evaluation of patient response to pain interventions such as intensive interdisciplinary pain treatment (IIPT). Objective To investigate the responsiveness to intervention of commonly used functional assessments among pediatric patients with pain undergoing IIPT. Design This retrospective cohort study collected self‐reported and performance‐based measures at admission and discharge from an IIPT program. The institutional review board approved study procedures. Setting IIPT program in an inpatient pediatric rehabilitation unit at a major midwestern children's hospital in the United States. Participants Demographics and clinical outcomes from 210 patients admitted between January 2014 and December 2022 were abstracted from the medical record. Patients were 9–19 years old (average age = 15), 75% were female, and 91% were White. The most common diagnosis was amplified musculoskeletal pain syndrome (26%). Interventions Patients attended an IIPT program for an average of 17 days and completed measures at admission and discharge. Main Outcome Measures Four performance‐based measures, WeeFIM II, Bruininks‐Oseretsky Test of Motor Proficiency (BOT‐2), 30‐second step test (30SST), grip strength, and 6‐minute walk test (6MWT), and one self‐report measure, Canadian Occupational Performance Measure (COPM). Results Self‐reported COPM and performance‐based 6MWT and 30SST scores showed the greatest responsiveness to intervention. The WeeFIM II and BOT‐2 scores were the least responsive to intervention. Conclusions The COPM, 6MWT, 30SST were the most responsive measures to intervention, capturing improvement among children with chronic pain completing an IIPT program; the WeeFIM II and BOT‐2 were the least responsive measures to intervention for this population.