Quality assessment of included studies using the Assessment of Multiple Systematic Reviews (AMSTAR).

<p>(SR) Systematic review; (M) Meta-analysis; (A1…A11) AMSTAR Items (please find in the AMSTAR Checklist in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0140426#pone.0140426.s003" target="_blank">S3 Appendix</a>), scored as 0 or 1; (AMSTAR) AMSTAR Score ranging from 0–11; (NA) Not Applicable</p><p>Quality assessment of included studies using the Assessment of Multiple Systematic Reviews (AMSTAR).</p

Provinces/regions with the highest HIV prevalence amongst key populations in China.

<p>Provinces/regions with the highest HIV prevalence amongst key populations in China.</p

Key partners in a multisectoral SESH program.

<p>Key partners in a multisectoral SESH program.</p

Overview of the dominant current sexual health delivery system and the SESH delivery system.

a<p>The current sexual health delivery approach as exemplified by a public-sector STD service.</p><p>CBO, community-based organization; MARP, most-at-risk population.</p

Individual-level characteristics of individuals at methadone clinics in Guangdong Province (N = 13,270).

<p>Individual-level characteristics of individuals at methadone clinics in Guangdong Province (N = 13,270).</p

Social ecological framework for African migrant patients’ trust of Chinese physicians.

<p>Social ecological framework for African migrant patients’ trust of Chinese physicians.</p

Distribution of delayed HIV and HCV testing rates at methadone clinics in Guangdong, China.

<p>Distribution of delayed HIV and HCV testing rates at methadone clinics in Guangdong, China.</p

Human Sex Ratio Under 16.

<p>Sex ratio is defined as the number of men per 100 women in populations less than 16 years old. Source: Sex Ratio: Central Intelligence Agency 2011, The World Factbook 2011, Washington DC.</p

Summary of results from included studies, focused on examining the relationship between high sex ratio communities and STD risk.

a<p>Sex ratio ranges reported as Mean (M) and Standard Deviation (SD).</p>b<p>Association is summarized as “not significant” if p>0.10.</p

Multivariate analysis of factors associated with delayed HIV testing at methadone clinics (N = 10,046).

*<p>103 individuals who had delayed HIV testing did not undergo HCV testing.</p>**<p>Total number of clients is the only clinic-level variable associated with delayed HIV testing in the multivariate analysis. Other non-significant clinic-level variables are not presented in the table. The complete results of the univariate analysis of clinic-level variables are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0066787#pone.0066787.s002" target="_blank">Table S1</a>.</p