Teen Births are the number of births per 1,000 female population, ages 15-19 and this measure is associated with unsafe sexual activity. Teen birth data are readily available and reliable for nearly all counties. We provided both the number of births and birth rates per 100,000 females aged 15 - 19.

Sexually Transmitted Infections (STI) are measured as the chlamydia incidence (number of new cases reported) per 100,000 population. We provided both the rate of Chlamydia cases per 100,000 population and the number of Chlamydia cases.

HIV prevalence measures the number of diagnosed cases of HIV in a county per 100,000 population. HIV is an important marker for a range of risky health behaviors. The County Health Rankings use disease-specific measures for ranking calculations only when no other reliable source for risk factor or outcome data is available. We provided both the HIV prevalence rate per 100,000 population and the number of HIV cases.