Table 3. Gay-identifying men eligible for PrEP in Australia, 2015.

	Assumed population proportion		Estimated number of gay men eligible for PrEP in Australia, per specified criteria
	Conservative scenario	Relaxed scenario	Conservative scenario	Relaxed scenario
	% (95% CIg)	% (95% CI)	NE (95% CI)	NE (95% CI)
HR-I: Being a regular sexual partner of an HIV-infected man with whom condoms were not consistently used in the last 3 months (partner has a detectable or unknown viral load)h	0.02% (0.01%-0.03)	0.02% (0.01%-0.03)	22 (11–33)	22 (11–33)
HR-II: At least one episode of receptive CLAIi with a casual male partner in the last 6 months j,k	6.1% (5.6%-6.7%)	15.5% (14.6%-16.4%)	6,640 (6,096–7,294)	16,872 (15,892 = 17,851)
HR-III: Rectal STI diagnosis (Gonorrhoea, Chlamydia or Syphilis) during the last 12 months l,m	4.9% (4.4%-5.4%)	10.6% (9.9%-11.3%)	5,334 (4,789–5,878)	11,538 (10,776–12,300)
HR-IV: Methamphetamine use in the last 3 monthsn	1.4% (1.1%-1.7%)	9.4% (8.7%-10.1%)	1,524 (1,197–1,850)	10,232 (9,470–10,994)
Overall at high risk for HIVo	9.7% (9.0%-10.4%)	28.4% (27.4%-29.5%)	10,558 (9,796–11,320)	30,913 (29,825–32,111)

g—95%CI– 95% Confidence Interval for proportions obtained from the Gay Community Periodic Surveys.

h—Regardless of whether the risk was ongoing.

i—CLAI–condomless anal intercourse.

j–The status of casual partners was not measured in the community samples recruited by GCPS.

k–GCPS assessed sexual practices in preceding 6 months (not in 3 months as required by PrEP eligibility criterion 2).

l–The estimate for behavioural criterion 3 is based any self-reported STI and anal swab, or blood test for Syphilis.

m–GCPS collected self-reported information about STI diagnoses in preceding 12 months (not in preceding 3 months or at screening as required by PrEP eligibility criterion 3).

n—GCPS measured use of crystal and speed. We took into account monthly or more frequent use of these drugs.

o—High risk for HIV was defined as “reporting any of the high risk factors listed below”.