This approach reduced the analysis sample size but resulted in associations with effects that were farther from the null for the SNPs in IL6, NAMPT and NFE2L2. While these findings did not achieve statistical significance after correction for type I error they provide support for the contention that phenotypic misclassification is a major issue reducing power and precision in case-control studies of ALI. Here, NFE2L2 is linked to acute respiratory distress syndrome.