Framework for Calculating Sample Size to Estimate Disease Prevalence

Abstract

Determining an appropriate sample size is a critical component of medical and veterinary research. In cross‑sectional studies, in particular, an adequate sample size is an essential part of accurately estimating the baseline prevalence of diseases or other health factors in human or animal populations. Proper sample size calculation ensures that the study includes enough humans or animals to estimate the prevalence of a disease, condition, parasite, pathogen, or to establish a baseline with acceptable precision. When sample sizes are too small, studies become underpowered and may fail to identify true effects or accurately characterize disease prevalence. In this paper, we provide a practical and accessible framework for calculating sample size for prevalence in medical and veterinary cross‑sectional research studies.