Table 5.

Estimated Bounds of the Probabilities of Selection Into the Study Among American Football Players, Conditional on CTE Status, Highest Level of Play, and Death, VA-BU-CLF Brain Bank, 2008–2019

Conditional Probability of Selection a	Lower Bound	Upper Bound
		1
		1
		1
		1
		1
		1

Abbreviations: CTE, chronic traumatic encephalopathy; VA-BU-CLF, Veterans Affairs–Boston University–Concussion Legacy Foundation.

^a  P(S|D+, E1, Death) denotes the probability of selection conditional on CTE diagnosis and having played high school football; P(S|D+, E2, Death) denotes the probability of selection conditional on CTE diagnosis and having played college football; and P(S|D+, E3, Death) denotes the probability of selection conditional on CTE diagnosis and having played professional football. P(S|D−, E1, Death) denotes the probability of selection conditional on no CTE diagnosis and having played high school football; P(S|D−, E2, Death) denotes the probability of selection conditional on no CTE diagnosis and having played college football; and P(S|D−, E3, Death) denotes the probability of selection conditional on no CTE diagnosis and having played professional football.