Comparison of a Medication Inventory and a Dietary Supplement Interview in Assessing Dietary Supplement Use in the...

Although dietary supplement use is common, its assessment is challenging, especially among ethnic minority populations such as Hispanics/Latinos. Using the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) (n = 16,415), this report compares two strategies for capturing dietary supplement use over a 30-day period: a medication-based inventory and a nutrition-based dietary supplement interview. Age-standardized prevalence was calculated across multiple dietary supplement definitions, adjusted with survey/nonresponse weights. The prevalence of dietary supplement use was substantially higher as measured in the dietary supplement interview, compared to the medication inventory: for total dietary supplements (39% vs 26%, respectively), for nonvitamin, nonmineral supplements (24% vs 12%), and for botanicals (9.2% vs 4.5%). Concordance between the two assessments was fair to moderate (Cohen's kappa: 0.31-0.52). Among women, inclusion of botanical teas increased the prevalence of botanical supplement use from 7% to 15%. Supplement assessment that includes queries about botanical teas yields more information about patient supplement use.