Data from the main instrument were keyed into appropriate files by a professional data entry firm. A double-entry protocol and standard data-cleaning procedures were followed to ensure accuracy. Data from the main instrument, physical examination, and risk behavior instru- ment for the seven CAWHS sites were merged into a single metafile, later divided into two metafiles, one each for male and female participants, and analyzed for the present report using SPSS Base 16.0 for Windows (SPSS, Inc., Chicago, IL).