Evaluating the diagnostic properties of the Whooley questionnaire as a case-finding instrument for depression among Chinese women during and after pregnancy

Figures & data

Figure 1. Participant flow chart.

Table 1. Characteristics of participants at antenatal stage and postnatal stage.

	Antenatal stage (n = 107)	Postnatal stage (n = 78)
Age in years, mean (SD)	32.4 (4.3)	32.3 (4.2)
Married, n (%)	101 (94.39)	73 (93.59)
Location of mother birth, n (%)
Hong Kong	62 (57.94)	47 (60.26)
Mainland China	41 (38.32)	28 (35.90)
Other	4 (3.74)	3 (3.85)
Number of years living in Hong Kong, n (%)
<5 years	5 (4.67)	3 (3.85)
5 to = >15 years	41 (38.32)	29 (37.18)
since birth	61 (57.01)	46 (58.97)
Level of education, n (%)
Primary	6 (5.61)	5 (6.41)
Secondary	31 (28.97)	18 (23.08)
University Degree or Above	70 (65.42)	55 (70.51)
Family income in HKD per month, n (%)
<$15,000	12 (11.21)	8 (10.26)
$15,000–$29,999	23 (21.50)	15 (19.23)
=>$30,000	72 (67.29)	55 (70.51)
Anyone else live in your home apart from partner? N (%)
No	47 (43.93)	35 (44.87)
Yes	60 (56.07)	43 (55.13)
Smoked tobacco during pregnancy, n (%)	1 (0.93)	1 (1.28)
Partner currently smoke tobacco, n (%)	18 (16.82)	13 (16.67)
Other at home currently smoke tobacco, n (%)	10 (9.43)	7 (9)
Employment status during pregnancy, n (%)
Full-time	76 (71.03)	58 (74.36)
Part-time	9 (8.41)	6 (7.69)
Casually	1 (0.93)	0 (0)
Did not work	21 (19.63)	14 (17.95)
Weeks of paid maternity leave, n (%)
0	9 (10.71)	6 (9.38)
10	44 (52.38)	29 (45.31)
12	2 (2.38)	2 (3.13)
14	25 (29.76)	23 (35.94)
16	4 (4.76)	4 (6.25)

Table 2. 2 × 2 Contingency table of diagnostic properties for the Whooley questionnaire.

	DSM-IV positive	DSM-IV negative	Sensitivity (95% CI)	Specificity (95% CI)	Positive predictive value (95% CI)	Negative predictive value (95% CI)	Positive likelihood value (95% CI)	Negative likelihood value (95% CI)	Diagnostic Odds Ratio (95% CI)
Antenatal (n = 107)
Whooley positive	15	3	78.9 (54.4–93.9)	96.6 (90.4–99.3)	83.3 (58.6–96.4)	95.5 (88.9–98.8)	23.2 (7.4–72.1)	0.2 (0.1–0.5)	106.3 (22.6–498.7)
Whooley negative	4	85
Postnatal (n = 78)
Whooley positive	10	3	76.9 (46.2–95.0)	86.2 (75.3–93.5)	52.6 (28.9–75.6)	94.9 (85.9–98.9)	5.6 (2.8–10.9)	0.3 (0.1–0.7)	20.74 (5.03–83.94)
Whooley negative	9	56

Table 3. Contingency table for stability of the DSM-IV and Whooley questionnaire.

Tool	Antenatal		Postnatal (% of those at antenatal)		McNemar Test (χ^2, p)
DSM-IV	Cases	14	Cases	4 (29)	χ^2 = 0.05, p = 1.00
			Non-Cases	10 (71)
	Non-Cases	64	Cases	9 (14)
			Non-Cases	55 (86)
Whooley	Cases	13	Cases	6 (46)	χ^2 = 1.8, p = 0.26
			Non-Cases	7 (54)
	Non-Cases	65	Cases	13 (20)
			Non-Cases	52 (80)