1. Summary of test accuracy at study level.

Study ID	Participants (n)	Primary threshold	Sensitivity (%)	Specificity (%)
Flicker 1997	299*	3.6	87	58
Garcia 2002	103	3.6	92	81
Goncalves 2011	204	4.1	72	67
Hancock 2009	144	3.6	86	39
Harwood 1997	177	3.3	100	78
Jorm 1991	69	3.6	71	80
Knaefelc 2003	323	3.6	94	47
Mackinnon 1998	106	3.6	90	65
Mulligan 1996	76	3.3	100	42
Narasimhalu 2008	576	3.4	86	78
Sikkes 2010	269*	3.3	96	42
Siri 2006	200	3.3	94	88
Tang 2003	189	3.4	88	75

Where multiple thresholds were reported, we used the value closest to 3.3 to populate this table

*Total number of participants adjusted to reflect numbers included in quantitative synthesis