Assessing the impact of missing data in youth overweight and obesity research: complete case analysis versus multiple imputation

Abstract

ABSTRACT Youth overweight and obesity (OWOB) surveillance often uses body mass index (BMI) derived from self-reported height and weight, but these measures can suffer from high proportions of missing data. Complete case analysis (CCA) is the most common approach to handle missing data, but this approach can introduce bias if missing data are not missing completely at random. Using BMI and related covariate data from 36,546 female and 37,126 male youth aged 12–19 years who participated in the COMPASS study in 2018/19, where approximately 30% of BMI data were missing, results and inference were compared between CCA and multiple imputation (MI) approaches to examine associations with youth BMI. Results of regression joint models showed contrasting findings between MI and CCA, highlighting that appropriate methodological choices in the handling of missing data are essential in youth OWOB research and that choices can impact research inference and thereby associated policy and programming recommendations.