Does a report of neurologic outcomes of 1950s high school football players have any bearing on today's athletes? The short answer is no, but I wouldn't have spent time examining this prospective cohort study if it wasn't worthwhile.
Source: Deshpande SK, Hasegawa RB, Rabinowitz AR, et al. Association of playing high school football with cognition and mental health later in life. JAMA Neurol. 2017;74(8):909-918;. doi:10.1001/jamaneurol.2017.1317. See AAP Grand Rounds commentary by Dr. David Urion (subscription required).
Don't read this study expecting it to help you make a decision on participation in high school football for your child or grandchild. However, except for the authors' puzzling final clause in the abstract of the report, we can learn a great deal from how these researchers approached this problem.
They utilized data from a prospective cohort of male high school students enrolled in the Wisconsin Longitudinal Study. They looked specifically at neurologic and mental health testing of almost 4000 men who graduated from high school in 1957, combing high school yearbook information to determine participation in organized contact sports, including football. They found no differences in cognition or depression outcomes at age 65 in the men who participated in high school football, compared to men who did not play football. (As an important aside, the investigators utilized propensity scoring to try to minimize confounding variables between subjects and controls. This is a bit like trying to make an observational study perform closer to the reliability of a prospective randomized trial, but of course it shouldn't be considered a substitute for such. We're still stuck with all the validity and bias concerns inherent in observational studies.)
You don't need to be too much of a student of medicine or statistics to see the problem with drawing too many conclusions from this study to the present day. Football is a lot different now than in the 1950s. Players are bigger, stronger, and faster now. Equipment is better, but that is a 2-edged sword since better protection, particularly head protection, can lead to more reckless behavior on the field. I tried to find reliable data on what football equipment might have been used in Wisconsin high schools in the 1950s but was unsuccessful. It is likely that by the early 1950s the days of the leather football helmets were long gone, replaced by plastic of varying quality. Face masks, consisting of a single tube in front of the mouth area, were just coming into use at professional levels in the mid-1950s.
So, this study is useful largely for establishing a baseline for neuropsychologic outcomes of high school football players from the 1950s, utilizing a prospective cohort rather than the more common convenience sample or subjects referred for specialty neurologic care, for example. It's a roadmap for study design for this particular outcome question, which is why I was so disappointed to see the end of the last sentence in the abstract: "... this study provides information on the risk of playing sports today that have a similar risk of head trauma as high school football played in the 1950s." How are we to know what would be a similar risk?
