✦ LIBER ✦
Biased Estimation of Adjusted Odds Ratios from Incomplete Covariate Data Due to Violation of the Missing at Random Assumption
✍ Scribed by Werner Vach; Sabina Illi
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 788 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0323-3847
No coin nor oath required. For personal study only.
✦ Synopsis
We investigate the possible bias due to an erroneous missing at random assumption if adjusted odds ratios are estimated from incomplete covariate data using the maximum likelihood principle. A relation between complete case estimates and maximum likelihood estimates allows us to identify situations w h m the bias vanishes. Numerical computations demonshate that the bias is most serious if the degne of the violation of the missing af random assumption depends on the value of the outcome variable or of the observed covariate. Implications for the analysis of prospective and retrospective studies are given.