Table 4.

Performance of the PHQ-9 in Detecting Depression in HIV positive patients (n = 413) in North West Province, South Africa

Cut-point	Sensitivity %	Specificity %	Percent correctly classified	LR+	LR-
(≥0)	100.00	0.00	12.59	1.000
(≥1)	100.00	21.05	30.99	1.2667	0.0000
(≥2)	98.08	33.80	41.89	1.4814	0.0569
(≥3)	88.46	49.31	54.24	1.7451	0.2340
(≥4)	84.26	61.22	64.16	2.1819	0.2513
(≥5)	82.69	68.42	70.22	2.6186	0.2530
(≥6)	76.92	77.29	77.24	3.3865	0.2986
(≥7)	71.15	83.93	82.32	4.4287	0.3437
(≥8)	57.69	88.92	84.99	5.2067	0.4758
(≥9)	57.69	92.80	88.38	8.0104	0.4559
(≥10)	48.08	95.57	89.59	10.4874	0.5433
(≥11)	40.38	97.51	90.31	16.1987	0.6114
(≥12)	36.54	98.06	90.31	18.8434	0.6472
(≥13)	28.85	98.06	89.35	14.8764	0.7256
(≥14)	26.92	98.61	89.59	19.4385	0.7410
(≥15)	23.08	99.45	89.83	41.6359	0.7735
(≥16)	17.31	99.72	89.35	62.4808	0.8292
(≥19)	11.54	99.72	88.62	41.6539	0.8871
(≥20)	5.77	99.72	87.89	20.8269	0.9449
(≥21)	3.85	99.72	87.65	13.8846	0.9642
(≥22)	1.92	100	87.65		0.9808
(≥22)	0.00	100	87.41		1.0000
Observations	ROC Area under the curve	Std. Error	95 % Confidence Interval
413	0.8488	0.0293	0.81	0.88