 The investigators will use data from the Wisconsin Longitudinal Study WLS of graduates from Wisconsin high schools in 1957 to investigate the link between playing high-school football and later life depression and cognitive impairment. The WLS has a number of attractive features that make it well-suited for such a study. First, it records whether study participants participated in high school football and also includes detailed measurements of later-life mental health, psychological well-being, and cognition. Second, it includes a rich set of baseline covariates which the investigators will use to construct matched sets of treated and control individuals, including family background, adolescent characteristics, educational and occupational achievement and aspirations. Third, the WLS is one of the few longitudinal data sets that includes an administrative measure of childhood cognition. In short, the WLS provides a large data set that facilitates comparing the later life mental health and cognitive ability of men who played high school football to those who did not, after carefully controlling for a range of potential confounders. The investigators will compare the primary outcomes of the treated subjects to the primary outcomes of the control subjects, after controlling for baseline covariates via full matching with a propensity score caliper. The primary outcomes are depression modified CES-D score and cognitive functioning average of z-scores for letter fluency and delayed word recall when participants are age 65. Secondary outcomes that include cognitive scores on various domains, the Spielberger anger index, the Spielberger anxiety index and a hostility index will also be analyzed. 