Department of Medicine, Division of Geriatric Medicine; Meyers Primary Care Institute
Comparative Effectiveness Research
Health Services Research
Comparative effectiveness research includes cohort studies and registries of interventions. When investigators design such studies, how important is it to follow patients from the day they initiated treatment with the study interventions? Our article considers this question and related issues to start a dialogue on the value of the incident user design in comparative effectiveness research. By incident user design, we mean a study that sets the cohort's inception date according to patients' new use of an intervention. In contrast, most epidemiologic studies enroll patients who were currently or recently using an intervention when follow-up began. We take the incident user design as a reasonable default strategy because it reduces biases that can impact non-randomized studies, especially when investigators use healthcare databases. We review case studies where investigators have explored the consequences of designing a cohort study by restricting to incident users, but most of the discussion has been informed by expert opinion, not by systematic evidence.
Rights and Permissions
This article is a U.S. Government work and is in the public domain in the USA.
DOI of Published Version
Pharmacoepidemiol Drug Saf. 2013 Jan;22(1):1-6. doi: 10.1002/pds.3334. Link to article on publisher's site
Pharmacoepidemiology and drug safety
Johnson ES, Bartman BA, Briesacher BA, Fleming NS, Gerhard T, Kornegay CJ, Nourjah P, Sauer B, Schumock G, Sedrakyan A, Sturmer T, West SL, Schneeweiss S. (2013). The incident user design in comparative effectiveness research. Meyers Primary Care Institute Publications. https://doi.org/10.1002/pds.3334. Retrieved from https://escholarship.umassmed.edu/meyers_pp/599