The impact of Grindr advertising on attendance and HIV testing by men who have sex with men at a sexual health clinic in northern Sydney.

Grindr is a geolocation smartphone application popular among men who have sex with men (MSM) to find sexual partners. We conducted a study to assess if attendance and HIV testing amongst MSM increased due to advertisements on Grindr that promoted our service. We measured clinic website hits by users clicking through from Grindr; we counted self-reported registrations that nominated referral from Grindr; and we compared new patient attendances and HIV tests in MSM with heterosexual men, for the 18 months preceding the intervention and the 18 months of the intervention. During the intervention the clinic's website received 11,799 unique hits from Grindr users. The average monthly rate of attendances by new MSM increased 70.3% from 19.0 to 32.3, compared with a 5.5% increase among new heterosexual men from 45.6 to 48.1. The average monthly rate of HIV tests among MSM increased 43.6% from 47.0 to 67.6, compared with a 3.9% increase amongst heterosexual men from 40.0 to 41.6. The MSM:heterosexual men rate ratio for new patient attendances changed from 0.42 to 0.67 (