Adaptation and Validation of the Washington Group/UNICEF Child Functioning Module in a Nationally Representative Sample of Canadian Children and Youth

Abstract Background: The Washington Group/UNICEF Child Functioning Module (WG/UNICEF CFM) was developed to assess functional difficulties among children and youth in national household surveys. The objective of this study was to examine the latent structure of the WG/UNICEF CFM using a graded response scale in a nationally representative sample of children and youth aged 5-17 years in Canada. Methods: Data for analyses come from the 2019 Canadian Health Survey on Children and Youth (n=33,420). Survey data were collected by Statistics Canada using an electronic questionnaire that was either self-completed online or interviewer-administered by telephone. To assess the latent structure of the WG/UNICEF CFM, analyses were conducted in four linked phases focusing on the following 9 domains: self-care, communication, learning, remembering, concentrating, accepting change, behavior, relationships, and emotions. An exploratory factor analysis was conducted first, followed by, confirmatory factor analysis (CFA), evaluations of measurement invariance across age and sex and external validity using structural equation modeling and instrumental variables. Results: Results indicated that a two-factor model best described the data, χ2(26, N = 16,810) = 619.076, p < .002, CFI = .98, TLI= .97, RMSEA = .037). Factor one represented Cognitive, Behavioural and Interpersonal Functional Difficulties; while Factor two represented Emotional Functional Difficulties. The external validity tests supported the distinction between the two factors by demonstrating stronger associations with instrumental variables measuring similar underlying constructs. Conclusions: The WG/UNICEF CFM has been predominantly evaluated in low-to-middle income countries. This study extends existing evidence by demonstrating the utility of the WG/UNICEF CFM for assessing childhood functional difficulties in a general population sample in a high-income country. The psychometric properties, including demonstrated reliability and validity, in combination with its ease of use and no cost, highlights the applicability of the WG/UNICEF CFM as a promising measure for assessing functional difficulties in in general population health surveys of children and youth.