MCE data recovery and validation

We obtained approval from the NIH Office of Human Research Protection (OHSRP #5743) and collaboration from Robert Frantz to recover, analyze, and interpret de-identified MCE data and study related materials stored on two 9-track magnetic tapes (see appendix fig A) and an extensive collection of paper documents, including numerous green-bar paper files, paper autopsy folders, original and supplementary grant proposals, data collection forms, and FORTAN coding sheets. Part 1 of the appendix describes the methods used to recover data, convert into a useable format, verify accuracy, and merge into a master file. For further validation, we compared each of the recovered MCE datasets with each other and with data reported in the 1989 study publication,¹⁵ the 1981 master’s thesis (Broste S K, Lifetable analysis of the Minnesota Coronary Survey http://www.psych.uic.edu/download/Broste_thesis_1981.pdf),⁷ and 1975 conference proceedings,^{16 17 18} as well as numerous other recovered MCE documents and data sources as described in part 1 of the appendix. Previous mentions of this study, including the recovered documents, refer to the “Minnesota Coronary Survey (MCS)” because prior to randomization there was an observational phase that lasted almost three years. We call it Minnesota Coronary Experiment (MCE) to emphasize that we are using the experimental, randomized controlled trial phase of the MCS.