The average age of study subjects was 36.5 and 75% were
white (with 18% of those being classed as Hispanic), 9.5% African American, and
5% Asian. Fifty-five per cent had education to degree level. Thirteen people in
the study (5.5%) were homeless.
Most people (92.5%) had tested for HIV in the last year – 2.25 times on average. The mean number of sexual partners in the last three months at baseline was 5.25, but condomless anal sex had only happened with one of them on average. Only a third of participants had had condomless
anal sex in the last three months with an HIV-positive or unknown-status
partner. About 10% had used methamphetamine and a third poppers in the last
There were a couple of slight differences between the study arms. More
people in the clinic-testing arm has actually used a home test in the past (ten
vs two individuals), and more of them had had STIs diagnosed (chlamydia and syphilis) in the last year (19% vs 8%). These differences were not significant though.
Men randomised to self-testing took 49% more HIV tests during the
15 months of the study than men in the control arm – 5.3 tests (one every 2.8
months) vs 3.6 tests (one every 4.1 months). This
averages out as an increase of 1.7 tests over the 15 months. Over 75% of
men in the self-testing arm took a test at least once every three months as
recommended, vs 54% in the control arm.
The men randomised to receive self-test kits could also take clinic tests; in fact 49% did, with 41% only taking self-tests, and 10% rejecting self-testing
and opting for clinic testing only. Of the 5.3 tests taken by men in the self-test arm, 1.4 were
actually at a clinic. But they still took more self-tests than the
total number of clinic tests by men in the control arm.
When only tests that could be independently verified were
included, there was a bigger difference between the arms with self-testers
reporting 4.7 verifiable tests in 15 months and control-arm testers 2.5, an 88%
Men in the self-test arm took fewer tests for STIs, however:
2.3 during the 15 months compared with 3.2 in the control arm.
It makes sense that because self-testers did not have to come to a clinic for HIV tests, they took fewer STI tests.
Interestingly, however, fewer self-testers than men in the control arm were
diagnosed with an STI in a screen at the end of the study: 5.4% vs 12.2%.
That was not quite statistically significant, but raises the possibility that
men in the self-test arm could have taken fewer STI tests because they experienced
There was no difference in HIV risk. Although men in the
self-testing arm were slightly more likely to report non-concordant condomless
anal sex, they reported slightly fewer sex partners, and no differences were
The men reported that they expected they would test more
often if they had access to self-tests; the median amount they would be willing
to pay for a test kit was $10 to $20. Twelve per cent said they would only use
self-tests if they were free.
Six men (3.4%) tested HIV positive during the study, four in
the self-testing arm (not a significant difference). This equates to an annual
incidence of 2.75%, compared with 0.4% among the general clinic-using
Seattle gay population.
All four positive men in the self-test arm had used a
self-test within two months of diagnosis. One tested positive at a test he took
at a clinic because his partner had just tested positive. He took a self-test,
which was also positive, between taking his clinic test and
receiving its result.
In the other three cases, none had their first positive
result via a home test. One had taken a negative home test two months prior to the end of the study – where the test he took, at his last clinic visit, was positive. In the
other two cases, they took clinic tests because they had symptoms suggesting
acute HIV infection – in one case only five days after his last negative self-test, and in the other a month after.