Table 3:

Accuracy of the cognitive charts for identifying participants with dementia in the training sample population (Canadian Study of Health and Aging) (22)

ParameterAt baseline
n = 7569
At 5-yr follow-up
n = 4401
At 10-yr follow-up
n = 2528
Combined*
Sensitivity (95% CI)80 (75 to 84)84 (79 to 88)76 (70 to 81)80
Specificity (95% CI)89 (88 to 90)81 (80 to 82)88 (86 to 89)87
PPV (95% CI)26 (24 to 29)22 (20 to 25)43 (38 to 47)29
NPV (95% CI)99 (99 to 99)99 (98 to 99)97 (96 to 98)99
LR+7.34.46.36.2
LR−0.220.200.270.23
  • Note: CI = confidence interval, LR+ = positive likelihood ratio, LR− = negative likelihood ratio, NPV = negative predictive value, PPV = positive predictive value.

  • * Combined values were obtained by modelling the relation between diagnoses and our classifier using repeated-measures logistic regression analyses. This takes into account the correlation between observations from a single participant; however, estimated sensitivities, specificities and predictive values are the same as if we had taken each individual observation independently. Consequently, we do not present confidence intervals for these combined values.