Benefits of epoetin alfa for cancer patients' quality of life are confirmed after modelling to account for missing data.
Incomplete data are inevitable in quality-of-life (QoL) studies involving cancer patients, since a proportion of patients will not complete the trial. Traditional analyses assume that such data are missing at random, but this assumption may be incorrect. We therefore applied mixed-effects statistical models to determine the effects of non-random missing data. Models were applied to results from a large-scale, randomised study of epoetin alfa versus placebo in 375 patients receiving non-platinum-based chemotherapy. The model suggested that QoL data were not missing at random and that analyses based on an assumption of random missing data gave an over-optimistic impression of QoL changes within treatment groups. However, sensitivity analysis demonstrated that the effectiveness of treatment with epoetin alfa compared to placebo in terms of QoL benefits remained highly significant, confirming the original conclusions of the study.
D000740:Anemia / Q000139:chemically induced / Q000188:drug therapy*; D000970:Antineoplastic Agents / Q000009:adverse effects; D003625:Data Collection; D004311:Double-Blind Method; D000068817:Epoetin Alfa; D004921:Erythropoietin / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000188:drug therapy / Q000503:physiopathology*; D010919:Placebos; D011788:Quality of Life; D011994:Recombinant Proteins
D000970:Antineoplastic Agents; D010919:Placebos; D011994:Recombinant Proteins; D004921:Erythropoietin; D000068817:Epoetin Alfa