The study cohort consisted of 1211 men aged 16 to 73 years attending a sexual health center for young people (site 1) or a genitourinary medicine clinic (site 2) in the United Kingdom.

• 研究对象包括年纪在16至73岁的1,211名男性，来自英国的青年性教育中心(来源1)或生殖秘尿医学门诊(来源2)。