Comparison of Demographic and Clinical Characteristics of Taiwan Biobank Participants with Nonparticipants

Background: This study investigated fundamental demographic variables within the Taiwan Biobank (TWBB) and compared them with national demographic statistics. Additionally, a matched cohort analysis compared TWBB participants with nonparticipants to uncover disparities in sociodemographic and clinical characteristics. Methods: A total of 128,663 individuals aged 30 to 70 without cancer were recruited within the TWBB, and 514,652 nonparticipants matched by age and sex were randomly selected from the National Health Insurance claims database. Sociodemographic variables, healthcare utilization metrics, underlying medical conditions, and subsequent mortality and cancer risk were analyzed. Results: TWBB participants were more likely to be female, older, married, higher educated, with higher incomes, and urban residency. Healthcare utilization metrics showed minimal differences. Pre-cohort entry, TWBB participants had a higher prevalence of certain medical conditions, such as peptic ulcer disease, osteoarthritis, osteoporosis, and uterine leiomyoma in females. During follow-up periods, elevated mortality rates were observed among TWBB participants but decreased cancer risk. Conclusion: The TWBB cohort exhibits disparities in sociodemographic and healthrelated attributes compared to the general population, comprising older, females, married, higher educated, higher income, and predominantly in urban areas. While mortality rates are slightly elevated within the TWBB cohort, cancer incidence rates are lower. Despite limitations in representativeness, the TWBB's size and exposure measures offer valuable insights into associations between exposures and health conditions.