Table 2.

Subgroup analyses of factors associated with 12-month AD prevalence.

Variable	Category	No of prevalence estimates	Mean prevalence, % (95% CI)	p-value
Individual characteristics
Age	0–5	17	16.3 (14.2; 18.8)	Ref
	6–12	81	9.4 (8.2; 10.8)	0.0005
	13–18	41	8.3 (6.6; 10.4)	< 0.0001
	19 +	11	9.3 (6.6; 13.0)	0.0140
Gender	Female	26	11.8 (9.9; 14.0)	Ref
	Male	26	8.2 (6.8; 9.9)	0.0063
Study characteristics
Sampling unit	Health insurance data	19	10.4 (7.7; 13.9)	Ref
	Pre/school	82	10.1 (9.1; 11.2)	0.8304
	Individual	22	7.7 (5.7; 10.3)	0.0847
	Other	4	17.0 (13.7; 20.8)	0.0925
Sampling	Random sampling	164	8.9 (8.0; 9.8)	0.0050
	Other	17	13.9 (11.6; 16.5)	Ref
Response rate	< 70%	19	11.0 (8.6; 13.9)	Ref
	70–79%	9	7.9 (5.7; 10.8)	0.1475
	≥ 80%	59	9.5 (8.1; 11.0)	0.3297
Outcome assessment measure	Self-reported symptoms	156	9.2 (8.3; 10.1)	Ref
	Self-reported ADa	10	7.0 (5.5; 8.8)	0.2066
	Other	24	10.8 (8.3; 14.1)	0.2247
Study configuration
Region	Asia	53	9.0 (6.9; 11.6)	0.9724
	Non-Asia	137	9.3 (8.5; 10.1)	Ref
Study period	1991–2000	85	10.4 (9.5; 11.5)	Ref
	2001–2010	88	7.4 (6.2; 8.8)	0.0004
	2011–2016	10	14.1 (12.5; 15.9)	0.1377

^aDiagnosed by a health care practitioner.