Data Set Error in: Pharmacogenetic Association of the NPPA T2238C Genetic Variant With Cardiovascular Disease Outcomes in Patients With Hypertension

Data Set Error: In the Original Contribution entitled “Pharmacogenetic Association of the NPPA T2238C Genetic Variant With Cardiovascular Disease Outcomes in Patients With Hypertension” published in the January 23, 2008, issue of JAMA (2008;299[3]:296-307), the authors identified an error in the data set used for analyzing the chlorthalidone vs doxazosin associations. The erroneous analytical data set was created at the data coordinating center in Houston, Texas, by merging 2 data files using a simple “merge” STATA command where a “match merge” should have been used. A “match merge” requires equality of the GenHAT participant identifiers from the paired records being merged, the ALLHAT variables being in one file and the genotype data in another. A simple “merge” assumes records from the merging files are in one-to-one correspondence, agreeing in order and number, and no check is done of the corresponding identifiers. The ALLHAT file had more observations than the GenHAT one, resulting in the mismatched pairing of records from the 2 files. This data set was used exclusively for the chlorthalidone vs doxazosin comparisons for the clinical outcomes (Table 4). A data set that was created separately and correctly was used for the baseline data (Table 1), main effects of the genetic variants (Table 2), chlorthalidone vs amlodipine and lisinopril comparisons (Table 3), and change in blood pressure data (Table 5). After reanalyzing the data with a corrected data set, the following changes affect the text of the article: