Have last-observation-carried-forward analyses caused us to favour more toxic dementia therapies over less toxic alternatives? A systematic review

摘要

BackgroundIntention-to-treat analysis is used in the analysis of randomized controlled trials to preserve trial power in the presence of missing subject data as well as to control for both known and unknown confounding factors. One form of intention-to-treat analysis is last-observation-carried-forward (LOCF). Concerns exist regarding whether it is appropriate to use LOCF in analyses involving progressive conditions or in situations where missing data are non-random (e.g., subjects drop out because of treatment side effects or differing disease severity).