Table 2.

Impact of varying probability thresholds: MCSA validation data set^∗

Probability	≥0.7	≥0.6	≥0.5	≥0.4
PPV	83%	79%	69%	64%
Specificity	93%	89%	67%	52%
NPV	60%	61%	73%	80%
Sensitivity	35%	43%	75%	87%
Likelihood ratio positive (95% CI)	5.01 (3.32–7.56)	3.84 (2.77–5.31)	2.25 (1.92–2.65)	1.81 (1.61–2.04)
AUC	64%	66%	71%	69%

Abbreviations: AUC, area under the curve; MCSA, Mayo Clinic Study of Aging; NPV, negative predictive value; PPV, positive predictive value.

^∗Data shown for algorithm using age, recall test z-score, and apolipoprotein ε4 carrier status.