Systemwide routine clinical assessment of functioning based on the ICF in China: Interrater reliability, convergent, known group, and predictive validity of the ICF generic

Abstract

Based on WHO's International Classification of Functioning, Disability and Health (ICF), the ICF Generic-6 is a minimum set of information on functioning to be routinely collected across health conditions and settings. This study aimed to validate the ICF Generic in daily routine clinical practice in Mainland China. Specific objectives were to a) analyse the interrater reliability, b) convergent validity, c) known group validity and d) predictive validity of the ICF Generic. Data from 4,510 patients with various diagnoses from 50 hospitals located in 20 provinces of Mainland China were collected by nurses who applied a 0 (no problem) to 10 (complete problem) numeric rating scale to each of six ICF categories of the ICF Generic at admission and study endpoint. 703 patients were rated independently by two investigators. Interrater reliability was evaluated with intraclass correlation coefficients (ICC). Convergent validity was evaluated with Spearman correlation coefficients between ICF Generic and SF-12 items. Known group-validity was examined by comparing discharge scores between different discharge destinations. Predictive validity was determined by employing ICF Generic baseline scores for estimating length of hospital stay and cost of in-hospital treatment. The interrater reliability of items and score of ICF Generic was good with ICCs ranging from 0.67 to 0.87. Spearman correlation coefficient analysis showed that ICF Generic items were correlated with respective SF-12 items. Discharge scores of patients differed significantly by discharge destination. ICF Generic admission score was a significant predictor of length of stay and treatment cost. The ICF Generic administered in combination with a 0 to 10 numeric rating scale is a reliable and valid tool for the collection of minimal information on functioning across various clinical settings.