A study of the diagnostic accuracy of the PHQ-9 in primary care elderly

Table 4 Sensitivity and specificity of each screening instrument using a broadened definition of depression*

Instrument and Cutpoint	Sensitivity (%) (95% CI)	Specificity (%) (95% CI)	+ Likelihood Ratio	- Likelihood Ratio
PHQ-9 Cutpoint
≥6	77	69	2.5	0.34
	(56-90)	(63-74)
≥7	77	77	3.3	0.31
	(56-90)	(70-81)
≥8	77	83	4.4	0.28
	(57-89)	(76-87)
≥9	71	87	5.2	0.34
	(51-85)	(80-91)
≥10	59	89	5.1	0.47
	(40-74)	(82-93)
PHQ-2 Cutpoint
≥1	82	67	2.5	0.26
	(62-94)	(61-71)
≥2	71	73	2.6	0.40
	(50-86)	(66-78)
≥3	53	90	5.5	0.52
	(35-67)	(85-95)
≥4	35	98	18.4	0.66
	(21-40)	(94-100)
≥5	18	98	9.2	0.84
	(7-22)	(95-100)
15-item GDS Cutpoint
≥4	94	4	0.98	1.63
	(85-99)	(1-5)
≥5	88	14	1.0	0.93
	(71-96)	(8-16)
≥6	81	62	2.1	0.30
	(60-93)	(55-65)
≥7	56	79	2.7	0.55
	(36-74)	(73-84)
≥8	31	90	3.3	0.76
	(16-46)	(86-95)

* Bolded cutpoints indicate the optimum balance between sensitivity and specificity.
^‡ CI = confidence interval.