Personality was assessed at ages 17 and 24 using the 198-item version of the Minnesota Personality Questionnaire (MPQ30). Alpha estimates for MPQ scales ranged from .78 to .94, with a mean coefficient alpha of .88. MPQ scores at ages 17 and 24 were averaged into a single score for each scale (test-retest intraclass correlation coefficient [ICC] range = .78–.86).
