title: Comparisons between ITT and treatment emergent adverse event analyses.
abstract: Different from the use of intention-to-treat (ITT) analysis for efficacy evaluation, many pharmaceutical companies currently use treatment emergent (TE) analysis for adverse event (AE) safety analysis. In the TE analysis, study period and AEs occurring after a pre-specified post-treatment window will not be included. One consideration for using the TE AE analysis is that including substantial off-drug period and events in the analysis may dilute the power for detecting safety signals especially if after discontinuation residual treatment effect diminishes quickly. We perform quantitative analyses to compare the unbiasedness and power of the ITT and TE AE analyses under several different settings and metrics (difference in rates and relative risk). Results show that unbiasedness and power are not always in the same direction. The choice of an approach for a particular trial should depend on the focus of the analysis. A data example is used to illustrate these points.
authors.affiliation: Biostatistics and Programming, Sanofi-Aventis, BX2-403A, 200 Crossing Boulevard, Bridgewater, NJ 08807, USA. hui.quan@sanofi-aventis.com
authors.forename: Hui
authors.initials: H
authors.lastname: Quan
authors.forename: Qiankun
authors.initials: Q
authors.lastname: Sun
authors.forename: Ji
authors.initials: J
authors.lastname: Zhang
authors.forename: Weichung J
authors.initials: WJ
authors.lastname: Shih
mesh_terms: D000077407:Cilostazol; D002986:Clinical Trials as Topic / Q000379:methods*; D003627:Data Interpretation, Statistical; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D015233:Models, Statistical; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use; D012107:Research Design; D018570:Risk Assessment / Q000379:methods; D013777:Tetrazoles / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D010726:Phosphodiesterase Inhibitors; D013777:Tetrazoles; D000077407:Cilostazol