Table 4. Impact of intervention on prevalence of ICD-10 CMD at 6 months, by baseline diagnostic group and facility type (secondary analyses).

Diagnostic group at baseline	Type of facility			p-value for effect modification
	All facilities	PHC	GPs
Screen positive cases (n=2429)
Collaborative Stepped Care	354 (28.8%)	196 (27.7%)	158 (29.9%)
Enhanced Usual Care	541 (38.6%)	375 (50.8%)	166 (29.4%)
Risk difference (95% CI)	-9.9% (-19.4%, -0.03%)	-23.1% (-42.1%, -4.2%)	-0.05% (-12.9%, 14.0%)	<0.001
Risk ratio (95% CI)	0.76 (0.57–1.02)	0.54 (0.37–0.81)	1.07 (0.66–1.74)	0.003
P-value	0.06	0.01	0.76
Sub-threshold cases (n=468)
Collaborative Stepped Care	30 (12.7%)	20 (12.4%)	10 (13.0%)
Enhanced Usual Care	77 (25.0%)	49 (31.2%)	28 (19.9%)
Risk difference (95% CI)	-12.3% (-23.5%, -1.1%)	-18.8% (-46.6%, 9.0%)	-6.9% (-19.3%, 5.5%)	0.18
Risk ratio (95% CI)	0.52 (0.29–0.96)	0.40 (0.11–1.38)	0.70 (0.31–1.59)	0.16
P-value	0.04	0.11	0.35