Development of a clinical decision tool to reduce diagnostic testing for primary aldosteronism in patients with difficult-to-control hypertension

Table 3 Test characteristics and proportion of patients spared intensive testing

	Cut-off value of the predicted probability
	1.0%	1.5%	2.0%	2.5%
Sensitivity	0.98 (0.96–0.99)	0.97 (0.91–0.99)	0.95 (0.89–0.98)	0.92 (0.83–0.97)
Specificity	0.09 (0.04–0.19)	0.16 (0.07–0.32)	0.25 (0.13–0.43)	0.33 (0.19–0.52)
Positive predictive value	0.05 (0.05–0.06)	0.06 (0.05–0.06)	0.06 (0.05–0.07)	0.07 (0.05–0.08)
Negative predictive value	0.99 (0.98–1.00)	0.99 (0.98–1.00)	0.99 (0.98–1.00)	0.99 (0.97–0.99)
Positive likelihood ratio	1.08 (1.00–1.17)	1.17 (1.01–1.33)	1.28 (1.04–1.52)	1.40 (1.06–1.75)
Negative likelihood ratio	0.18 (0.07–0.39)	0.19 (0.08–0.38)	0.20 (0.08–0.43)	0.24 (0.09–0.49)
Proportion of patients spared intensive testing	8% (4–18)	15% (7–31)	24% (12–41)	32% (18–50)

The positive likelihood ratio tells you how much to increase the probability of having a disease, given a positive test result. The negative likelihood ratio tells you how much to decrease the probability of having a disease, given a negative test result. The proportion of patients spared intensive testing is the proportion of patients with a predicted probability equal to or below the cut-off value. Estimates and corresponding Bootstrap-based 95% confidence intervals are presented for different cut-off values of the predicted probability by the diagnostic tool.

ISSN: 1472-6823