Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Protocol for an Observational Study on the Effects of Playing High
  School Football on Later Life Cognitive Functioning and Mental Health   A potential causal relationship between head injuries sustained by NFL
players and later-life neurological decline may have broad implications for
participants in youth and high school football programs. However, brain trauma
risk at the professional level may be different than that at the youth and high
school levels and the long-term effects of participation at these levels is
as-yet unclear. To investigate the effect of playing high school football on
later life depression and cognitive functioning, we propose a retrospective
observational study using data from the Wisconsin Longitudinal Study (WLS) of
graduates from Wisconsin high schools in 1957.
  We compare 1,153 high school males who played varsity football to 2,751 male
students who did not. 1,951 of the control subjects did not play any sport and
the remaining 800 controls played a non-contact sport. We focus on two primary
outcomes measured at age 65: a composite cognitive outcome measuring verbal
fluency and memory and the modified CES-D depression score. To control for
potential confounders we adjust for pre-exposure covariates such as IQ with
matching and model-based covariate adjustment. We will conduct an ordered
testing procedure that uses all 2,751 controls while controlling for possible
unmeasured differences between students who played sports and those who did
not. We will quantitatively assess the sensitivity of the results to potential
unmeasured confounding. The study will also consider several secondary outcomes
of clinical interest such as aggression and heavy drinking. The rich set of
pre-exposure variables, relatively unbiased sampling, and longitudinal nature
of the WLS dataset make the proposed analysis unique among related studies that
rely primarily on convenience samples of football players with reported
neurological symptoms.

23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph