Table 2.

Subgroup analyses by age, sex, research sites and region

Subgroup	Prevalence (%)	95% CI (%)	Heterogeneity
			I2 (%)	P value
Age
60–69	11.98	3.91 to 23.62	98.1	0.000
70–79	26.79	8.71 to 50.36	99.7	0.000
80–89	51.31	47.20 to 96.33	99.6	0.000
≥90	57.53	8.18 to 98.09	99.0	0.000
Sex
Females	8.26	5.88 to 11.00	87.4	0.000
Males	18.65	0.83 to 51.61	99.9	0.000
Research sites
Health examination centre	43.83	19.39 to 69.94	99.8	0.000
Nursing homes	16.26	4.55 to 33.29	93.2	0.000
Community	12.21	3.46 to 25.34	99.8	0.000
Region
Turkey, China	24.34	14.03 to 36.38	99.6	0.000
Norway, Denmark, Britain	8.23	6.36 to 10.35	90.2	0.000