CHICAGO (AP) — Fewer than 1 in 4 high school students who've had sex have ever been tested for HIV. That's according to a government study that found the rate didn't budge over eight years, despite recommendations for routine tests.

Young adults fared slightly better, although testing rates have declined in black women, and they're a high-risk group.

The Centers for Disease Control and Prevention and an influential preventive health panel recommend routine HIV testing at least once for teens and adults. They also advise at least yearly screening for high-risk patients including those with multiple sex partners, gay or bisexual boys and men and injection drug users.

Some teens and adults underestimate their risk and some doctors are unaware of the recommendations.

The study was published online Tuesday in the journal Pediatrics.