Observational analogs of randomized clinical trials (RCTs) are well accepted in the study of disease risk factors, diagnosis, and prognosis. There is controversy about observational studies when the focus is on the intended benefit due to lack of blinding and poor control for unmeasured confounding. Well-designed randomized clinical trials are costly both in time and money. Therefore, existing databases are used increasingly and are often the only feasible source with which to examine delayed health effects. We reviewed the reasons for possible discrepancies between RCTs and observational studies. There can be different patient populations, differences in therapeutic regimen, control of confounding, follow-up, measuring outcome, and differences arising from the intention-to-treat analysis. Observational studies cannot replace trials, nor do trials make observational studies unnecessary. Both designs are susceptible to particular bias, so neither provides perfect information. (HEPATOLOGY 2006;44:1075-1082.).
Beyond randomized controlled trials: A critical comparison of trials with nonrandomized studies
Sorensen, HT., Lash, T., & Rothman, K. (2006). Beyond randomized controlled trials: A critical comparison of trials with nonrandomized studies. Hepatology, 44(5), 1075-1082.
Abstract
Publications Info
To contact an RTI author, request a report, or for additional information about publications by our experts, send us your request.
Meet the Experts
View All ExpertsRecent Publications
OCCASIONAL PAPER
The Preschool Entitlement
OCCASIONAL PAPER
Culturally informed community engagement
Article
Does the relationship between alcohol retail environment and alcohol outcomes vary by depressive symptoms? Findings from a US Survey of Black, Hispanic and White drinkers
Article