Table 2. Prevalence of benign prostatic hyperplasia in mainland China and subgroup analysis.

Variable		Number of surveys	Sample size	BPH cases	Prevalence (per 100) [95%CI ]	I2 (%)
Overall prevalence		14	25040	8584	36.6 [29.6–43.6]	99.3
Location	Urban	9	17844	6196	41.5 [34.5–48.4]	98.9
	Rural	4	3408	1309	38.6 [22.7–54.6]	99.2
Age	40–49	7	3596	84	2.9 [1.4–4.4]	89.4
	50–59	10	4093	961	29.0 [21.5–36.5]	97.0
	60–69	11	6166	2684	44.7 [37.8–51.6]	96.6
	70–79	8	4044	2274	58.1 [49.5–66.7]	96.8
	80–	8	1268	879	69.2 [59.8–78.6]	92.8
Survey Year	1981–1990	1	647	290	44.8 [41.0–48.7]	NA
	1991–2000	6	11052	3935	35.2 [24.8–45.7]	99.3
	2001–2010	5	7258	2545	41.1 [23.2–58.9]	99.6
	2011–present	2	6083	1814	25.7 [16.3–35.1]	92.7
Quality Score	0–5	2	900	3473	33.1 [10.4–55.9]	99.2
	6–10	12	7684	21567	37.2 [29.4–44.9]	99.3
Survey method	Random	3	4661	1418	33.1 [14.4–51.8]	99.5
	Cluster random	2	8652	2371	25.9 [17.5–34.4]	98.7
	Stratified	3	2352	712	30.3 [16.9–43.8]	97.7
	Multi–stage	6	9375	4083	45.1 [33.1–57.0]	99.3
Diagnostic criteria	A	4	5129	1192	23.7 [20.8–26.6]	78.6
	B	6	13623	4708	39.5 [28.2–50.8]	99.5
	C	4	6288	2684	45.2 [29.8–60.7]	99.3

BPH: benign prostatic hyperplasia; NA: not available; Diagnostic criteria A: Prostate volume > 20 ml and medical history or questionnaire survey.

B: Prostate volume > 20 ml and Qmax < 15 ml/s or10 ml/s and IPSS > 7.

C: Other criteria (criteria from academic conferences in China or the Guideline on diagnosis and BPH from the Chinese Medical Association).