Patient Health Questionnaire-9 and 17-item Hamilton Depression Rating Scale for detecting post-stroke depression in cerebral infarction

Table 1 Comparison of general data between two groups, n (%)/mean ± SD/median (interquartile range)

Variable	PSD group (n = 112)	Non-PSD group (n = 233)	t/χ2/Z value	P value
Sex			3.72	0.054
Male	54 (48.21)	138 (59.23)
Female	58 (51.79)	95 (40.77)
Age (years)	65.73 ± 10.24	62.18 ± 11.35	2.816	0.005
Years of education (years)	8.42 ± 3.67	8.89 ± 3.82	1.087	0.278
Marital status			1.03	0.598
Married	89 (79.46)	195 (83.69)
Divorced/widowed	18 (16.07)	31 (13.30)
Single	5 (4.46)	7 (3.00)
Cerebral infarction location			2.15	0.341
Anterior circulation	52 (46.43)	124 (53.22)
Posterior circulation	38 (33.93)	76 (32.62)
Multiple	22 (19.64)	33 (14.16)
NIHSS score (points)	6 (3, 9)	4 (2, 7)	-3.624	< 0.001
BI (points)	65 (45, 80)	80 (60, 95)	-4.518	< 0.001
Assessment time (days)	42 (21, 78)	38 (18, 72)	-1.236	0.216
Comorbidities
Hypertension	71 (63.39)	134 (57.51)	1.103	0.294
Diabetes mellitus	48 (42.86)	72 (30.90)	4.762	0.029
Coronary heart disease	29 (25.89)	51 (21.89)	0.689	0.407

BI: Barthel Index; NIHSS: National Institutes of Health Stroke Scale; PSD: Post-stroke depression.

Table 2 Comparison of scale scores between two groups, median (interquartile range)

Scale	PSD group (n = 112)	Non-PSD group (n = 233)	Z value	P value
HAMD-17	14 (10, 19)	4 (2, 6)	-12.347	< 0.001
PHQ-9	12 (8, 16)	3 (1, 5)	-11.862	< 0.001

HAMD-17: 17-item Hamilton Depression Rating Scale; PHQ-9: Patient Health Questionnaire-9; PSD: Post-stroke depression.

Table 3 Comparison of diagnostic efficacy of two scales at different cutoff values

Scale and cutoff value	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	+LR	-LR	Youden Index	Kappa value
HAMD-17 ≥ 7 points	88.39	79.83	67.81	93.47	4.38	0.15	0.682	0.632
PHQ-9 ≥ 5 points	91.07	68.67	58.29	94.12	2.91	0.13	0.597	0.521
PHQ-9 ≥ 7 points	83.04	81.12	67.88	90.87	4.4	0.21	0.642	0.606
PHQ-9 ≥ 10 points	73.21	89.27	76.64	87.39	6.83	0.3	0.625	0.632

HAMD-17: 17-item Hamilton Depression Rating Scale; NPV: Negative predictive value; PHQ-9: Patient Health Questionnaire-9; PPV: Positive predictive value; +LR: Positive likelihood ratio; -LR: Negative likelihood ratio.

Table 4 Receiver operating characteristic curve analysis results of two scales

Scale	AUC	95%CI	Optimal cutoff (points)	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	+LR	-LR	Youden Index
HAMD-17	0.891	0.854-0.928	7	88.39	79.83	67.81	93.47	4.38	0.15	0.682
PHQ-9	0.867	0.826-0.908	7	83.04	81.12	67.88	90.87	4.4	0.21	0.642

Comparison of area under the curve between two scales, Z = 1.426, P = 0.154. AUC: Area under the curve; HAMD-17: 17-item Hamilton Depression Rating Scale; NPV: Negative predictive value; PHQ-9: Patient Health Questionnaire-9; PPV: Positive predictive value; +LR: Positive likelihood ratio; -LR: Negative likelihood ratio.

Table 5 Agreement analysis between two scales and gold standard diagnosis

Scale and cutoff value	Positive cases	True positive	False positive	True negative	False negative	Kappa value	P value
HAMD-17 ≥ 7 points (optimal cutoff value)	146	99	47	186	13	0.632	< 0.001
PHQ-9 ≥ 5 points	175	102	73	160	10	0.521	< 0.001
PHQ-9 ≥ 7 points (optimal cutoff value)	137	93	44	189	19	0.606	< 0.001
PHQ-9 ≥ 10 points	107	82	25	208	30	0.632	< 0.001

HAMD-17: 17-item Hamilton Depression Rating Scale; PHQ-9: Patient Health Questionnaire-9.