Poor agreement between measured and perceived body weight status, and determinants of misclassification among adults in Cameroon: a cross-sectional study

Body weight misperception can adversely affect obesity prevention and control efforts. Despite rising trends in the prevalence of overweight and obesity in Cameroon, limited evidence exists on the magnitude and determinants of weight misperception. This study aimed to examine the prevalence and drivers of body weight misperception, underestimation and overestimation among adults in Cameroon. We conducted a secondary analysis of cross-sectional data collected in 2016 from 1,139 adults in Buea, a semi-urban town in Cameroon. Objective weight status was ascertained via measured body mass index (BMI), while a questionnaire assessed self-perceived body weight status. We evaluated agreement between both methods using the kappa statistic and fitted Poisson regression models to identify sociodemographic and behavioural factors predicting misperception. The prevalence of any misperception in the total sample was 43.0% (95% CI 40.1–45.9), whereas weight underestimation in those with BMI-defined overweight or obesity was 82.8% (95% CI 79.2–85.9). For individuals with a normal BMI, the prevalence of weight overestimation was 4.9% (95% CI 3.4-7.0). Overall, the agreement between the objective and perceived weight status was poor (κ = 0.13). Any misperception was higher among participants aged 45–54 years and those aged 55 years or older, women, married individuals and those who consumed high amounts of alcohol. Overestimation was more prevalent among those aged 55 years or older and among married persons, while underestimation was more common among smokers and those reporting good-to-excellent health status. We found poor agreement between self-perceived and measured body weight in this study, approximately two in five adults misclassified their weight status, and four in five people underestimated their body weight. Public health strategies are needed to improve awareness of weight status and address the related drivers of misperception to optimise health outcomes in Cameroon.