“…Several guidelines have been published in recent years on the issue of missing data in clinical trials (National Research Council, ; Committee for Medicinal Products for Human Use (CHMP), ; Burzykowski et al, ; Carpenter & Kenward, ) and for CEA in particular (Briggs, Clark, Wolstenholme, & Clarke, ; Burton, Billingham, & Bryan, ; Faria, Gomes, Epstein, & White, ; Manca & Palmer, ; Marshall, Billingham, & Bryan, ). Key recommendations include: - taking practical steps to limit the number of missing observations;
- avoiding methods whose validity rests on contextually implausible assumptions, and using methods that incorporate all available information under reasonable assumptions; and
- assessing the sensitivity of the results to departures from these assumptions.
…”