Figure 3. Course of Functioning From Baseline to 12-Month Follow-up by Brain Age Gap.

Global Assessment of Functioning Scale (GAF) scores at baseline and 12-month follow-up among clinically high-risk individuals according to whether their brain age gap scores were in the expected range vs underestimated or overestimated using the mean absolute error of the brain age model as a threshold (underestimated: brain age gap < −1.5; expected: −1.5 ≤ brain age gap ≤1.5 years; and overestimated: 1.5 < brain age gap). Mean GAF scores improved from baseline to follow-up when the brain age gap was within the mean absolute error range (P < .001) but did not improve for individuals with an underestimated or overestimated brain age gap. Clinically high-risk individuals who converted to psychosis were disproportionately represented among those with an overestimated brain age gap (underestimated, n = 0; expected, n = 8; overestimated, n = 9), and a similar pattern was observed even when converters were excluded (eFigure 6 in the Supplement).

^aP < .001, corrected.