Table 4.

Mental health service uptake and GP utilization rates stratified by PHQ-9 and doctor identification status at baseline

Self-reported health service use	12-week follow-up			26-week follow-up			52-week follow-up			Cumulative service uptake/use over 12 months
	n (%)	n (%)	P value	n (%)	n (%)	P value	n (%)	n (%)	P value	n (%)	n (%)	P value
1) Among the entire longitudinal cohort	PHQ+ve	PHQ−ve		PHQ+ve	PHQ−ve		PHQ+ve	PHQ−ve		PHQ+ve	PHQ−ve
Consulted a psychiatrist or psychiatric clinic in last 3 months	40 (13.3%)	73 (2.7%)	<0.001*	44 (16.2%)	90 (3.0%)	<0.001*	77 (19.7%)	116 (3.8%)	<0.001*	97 (21.7%)	178 (5.2%)	<0.001*
Received professional psychological treatment or counselling from GP in last 3 months	31 (10.3%)	34 (1.3%)	<0.001*	17 (6.3%)	18 (0.6%)	<0.001*	13 (3.3%)	14 (0.5%)	<0.001*	52 (11.6%)	60 (1.8%)	<0.001*
Received professional psychological treatment or counselling from psychologist in last 3 months	5 (1.7%)	12 (0.4%)	0.022*	6 (2.2%)	11 (0.4%)	0.002*	10 (2.6%)	14 (0.5%)	<0.001*	16 (3.6%)	30 (0.9%)	<0.001*
Received professional psychological treatment or counselling from social worker in last 3 months	11 (3.6%)	11 (0.4%)	<0.001*	8 (3.0%)	14 (0.5%)	<0.001*	6 (1.5%)	12 (0.4%)	0.012*	18 (4.0%)	32 (0.9%)	<0.001*
Received professional psychological treatment or counselling from other people in last 3 months	4 (1.3%)	9 (0.3%)	0.035*	1 (0.4%)	11 (0.4%)	1.000	6 (1.5%)	5 (0.2%)	0.001*	9 (2.0%)	24 (0.7%)	0.011*
Mean number GP consultations in past 4 weeks, mean (SD)	1.063 (1.439)	0.947 (1.287)	0.142	0.944 (1.307)	0.874 (1.301)	0.396	1.124 (1.646)	0.926 (1.325)	0.023*	1.076 (1.205)	0.919 (1.017)	0.008*
2) Among the PHQ+ve longitudinal cohort	Detected	Not detected		Detected	Not detected		Detected	Not detected		Detected	Not detected
Consulted a psychiatrist or psychiatric clinic in last 3 months	18 (25.0%)	21 (9.3%)	<0.001*	27 (35.5%)	16 (8.3%)	<0.001*	42 (40.4%)	34 (12.0%)	<0.001*	54 (45.0%)	42 (13.0%)	<0.001*
Received professional psychological treatment or counselling from GP in last 3 months	15 (20.5%)	15 (6.6%)	<0.001*	12 (16.2%)	3 (1.6%)	<0.001*	6 (5.8%)	7 (2.5%)	0.120	29 (24.2%)	21 (6.4%)	<0.001*
Received professional psychological treatment or counselling from psychologist in last 3 months	3 (4.1%)	2 (0.9%)	0.095	2 (2.7%)	3 (1.6%)	0.622	6 (5.8%)	4 (1.4%)	0.026*	8 (6.7%)	7 (2.1%)	0.033*
Received professional psychological treatment or counselling from social worker in last 3 months	5 (6.8%)	6 (2.6%)	0.144	4 (5.3%)	4 (2.1%)	0.226	4 (3.9%)	2 (0.7%)	0.045*	9 (7.5%)	9 (2.8%)	0.031*
Received professional psychological treatment or counselling from other people in last 3 months	2 (2.8%)	2 (0.9%)	0.246	0 (0.0%)	1 (0.5%)	1.000	2 (1.9%)	4 (1.4%)	0.660	3 (2.5%)	6 (1.8%)	0.707
Mean number GP consultations in past 4 weeks, mean (SD)	1.452 (2.069)	0.927 (1.146)	0.042*	1.074 (1.399)	0.866 (1.272)	0.293	1.409 (2.062)	1.014 (1.443)	0.074	1.290 (1.543)	0.984 (1.027)	0.046*

Displayed above are counts and percentages of ‘Yes’ respondents among each group. Corresponding values of ‘No’ respondents are omitted. Patients were stratified according to their PHQ-9 screening outcome at baseline, and whether they were detected or not detected with depressive disorder by study doctor at baseline. Cumulative service use for mental health service uptake refers to having reported the particular mental health service use at least once during the 12-month follow-up period. Cumulative service use for GP consultations refers to average number of GP consultations in the past 4 weeks over the three follow-up time points.

*Significant difference (P < 0.05) between groups by chi-square test or Fisher exact test, as appropriate.