Table 3.

Combinations of cutoff levels with the three highest Youden indices

Cutoff levels	Sensitivity 95% CI	Specificity 95% CI	Youden index 95% CI
Y ≥2 or M/AL ≥5	0.76 (0.67, 0.84)	0.88 (0.64, 0.99)	0.64 (0.31, 0.82)
Y ≥2 or M/AL ≥3	0.87 (0.79, 0.92)	0.77 (0.50, 0.93)	0.63 (0.29, 0.86)
Y ≥2 or M/AL ≥4	0.79 (0.70, 0.86)	0.82 (0.57, 0.96)	0.61 (0.27, 0.82)

Notes: Youden index =sensitivity +specificity −1. Bold combination best fit with rule of thumb sensitivity > specificity, sensitivity and specificity both in 0.70–0.80 ranges, and Youden index high.

Abbreviations: CI, confidence interval; M/AL, Maybe/A Little; Y, Yes.