How good are observational studies in assessing psychiatric treatment outcomes?

摘要

In comparative effectiveness studies, treatment effects are calculated by contrasting outcomes between patients who have been assigned to different treatment groups. While randomized treatment assignments are preferred, constraints on resources, timeliness of results, ethical concerns, low frequency of outcomes, and demands for patient subgroup analyses often lead psychiatric investigators to rely on observational data after patients and their physicians have self-selected their treatments (1). With observational studies, researchers must account for how patients select their treatment to properly adjust estimates of treatment effects that control for these selection biases.