I Want the Kit (IWTK) - What's Your Risk for Having a Sexually Transmitted Infection (STI)?

Background: IWTK (an internet program that tested for chlamydia, gonorrhea, and trichomonas from self-collected genital swabs) has an educational component that informs users about STIs and uses a quiz for sexually active people to estimate their risk of having an STI.  

Methods:  November 2010-2013, IWTK asked users to take a six-question quiz:

• Are you ≤ 25 years old?
• Have you had new or multiple sex partners, last 90 days?
• Do you have more than one current sex partner?
• Have you been told you had, or treated for an STI in the past?
• How many sex partners have you had, last 90 days?
• Do you use a condom with sex?

Points were assigned to responses for each question and scores calculated.  A score of 7-10 was considered very high risk; 4-6, high risk; 2-3, intermediate risk; 0-1, low risk.

Results:  1,168/2,460 females (47.5%) and 841/1,680 males (50.1%) who returned kits provided risk scores.  Of females, 233/1168 (19.9%) were very high risk; 708/1168 (60.6%), high risk; 171/1168 (14.6%), intermediate risk; 56/1168 (4.8%), low risk.  Trend for female infection by risk score category: p<0.001. Of males, 179/841 (21.3%) were very high risk; 407/841 (48.4%), high risk; 198/841 (23.5%), intermediate risk; 57/841 (6.8%), low risk.  Trend for male infection by risk score category:  p=0.001.  Of very high risk females, 42/233 (18.0%) were infected (chlamydia, gonorrhea, and/or trichomonas); high risk, 80/708 (11.3%); intermediate risk, 12/171 (7.0%); low risk, 4/56 (7.1%).  Of very high risk males, 22/179 (12.3%) were infected; high risk, 26/407 (6.4%); intermediate risk, 7/198 (3.5%); low risk, 2/57 (3.5%). There was a higher infection rate in the high risk group in females than males; (11.3% versus 6.4%, p=0.007).

Conclusions:  Risk scores may predict the likelihood of having an STI. The score may help a user decide whether to order a test kit.