Table 3.

Results of the fully-adjusted multinomial regression model predicting concordant use of pre-exposure prophylaxis (PrEP) with participant on PrEP only as the reference category (n = 3140)

	Partner on PrEP Only		Both Participant and Partner on PrEP		Unknown Partner PrEP Use
Variables	RRR+	95% CI	RRR	95% CI	RRR	95% CI
Age	0.97*	0.94–1.00	0.98*	0.96–1.00	0.98*	0.95–1.00
Sexual orientation identity (Ref: non-bisexual)
Bisexual	2.08*	1.05–4.13	0.46	0.20–1.03	2.83**	1.55–5.18
Straight/other	1.02	0.06–18.31	0.00***	0.00–0.00	4.05	0.39–41.98
Gender (Ref: cisgender male)
Transgender male	0.23	0.02–2.57	0.94	0.16–5.66	0.62	1.16–2.47
Race/ethnicity (Ref: White)
Black	2.26	0.79–6.50	2.81	0.98–8.08	1.78	0.67–4.70
Latino	0.37*	0.17–0.82	0.95	0.52–1.72	1.40	0.79–2.51
Other/multiracial	0.87	0.42–1.82	1.65	0.88–3.08	1.58	0.83–3.00
Education (Ref: less than Bachelor’s degree)
Bachelor’s degree or higher	0.59	0.34–1.02	1.07	0.65–1.74	0.38***	0.23–0.67
Region (Ref: South)
Northeast	0.47*	0.23–0.98	0.85	0.46–1.60	0.61	0.32–1.16
Midwest	0.71	0.33–1.55	0.98	0.49–1.98	0.81	0.40–1.63
West	0.60	0.30–1.19	0.50*	0.27–0.93	0.59	0.32–1.07
Other (e.g., US possession, military overseas)	0.00***	0.00–0.00	1.68	0.24–11.80	0.85	0.09–7.63
Relationship agreement with main partner (Ref: monogamous)
Monogamish	0.75	0.24–2.34	1.61	0.62–4.20	0.34	0.12–1.01
Open	0.97	0.50–1.87	1.58	0.81–3.09	0.18***	0.10–0.35
No agreement	0.78	0.30–1.98	0.49	0.18–1.37	0.98	0.48–2.01
Relationship duration with main partner (Ref: 1–5 years)
Less than 1 year	2.46**	1.34–4.52	1.46	0.83–2.60	2.04*	1.17–3.54
More than 5 years	1.26	0.61–2.60	2.52**	1.41–4.51	1.03	0.51–2.06
Any condomless anal sex with main partner (past 6 months; Ref: no)
Yes	1.34	0.74–2.45	2.56**	1.41–4.66	0.48**	0.29–0.78
Any condomless anal sex with male casual sex partners (past 6 months; Ref: no)
Yes	0.29***	0.16–0.51	0.65	0.38–1.12	0.38***	0.23–0.64
Sexual position identity (Ref: top)
Top	1.90	0.73–4.94	3.55**	1.51–8.34	1.03	0.44–2.41
Versatile	1.99	0.93–4.27	2.37*	1.17–4.80	1.69	0.92–3.10
Any STI diagnosis (past 6 months; Ref: no)1
Yes	1.09	0.42–2.78	2.29*	1.13–4.62	0.51	0.19–1.42
HIV-status (Ref: HIV-negative)
Unknown	4×107***	NR++	--	--	4×107***	NR
Main partner HIV-status (Ref: HIV-negative)
Unknown	0.00***	0.00–0.00	0.00***	0.00–0.00	2.43*	1.22–4.84

Notes: Neither participant nor partner on PrEP category is shown because of redundancy with Table 2. Values with 0.00 are non-zero, rounded numbers.

^*p < 0.05;

^**p < 0.01;

^***p < 0.001.

⁺RRR = relative risk ratio; this is the multinomial logistic regression coefficient exponentiated (i.e., e^b).

⁺⁺NR = not reported due to large values.

^--Values are not reported because of concern of a spurious finding since zero individuals fall within this category (i.e., RRR = 3.46***, 2.16–5.56 95% CI).

¹Sexually transmitted infection diagnoses included chlamydia, gonorrhea, and syphilis.