HOME DRUG TEST RESULTS MAY NOT ADD UP TO TRUTH

Study Shows Many Can Be Manipulated, Give False Positives

Parents, beware of home drug-testing kits being sold on the Internet - a
new study reports they're not always accurate, or even reassuring when they
do work.

"There's actually more information out there on the Web about how to beat
drug testing regimens than there is on how to do them properly," said Dr.
Sharon Levy, a pediatrician who specializes in substance abuse treatment at
Harvard Medical School and Children's Hospital in Boston.

Levy and two colleagues evaluated eight drug-testing kits she found being
sold on the Internet.

Their report appears in the April issue of the journal Pediatrics.

The kits, many of which were sold on multiple Web sites, included breath
and saliva tests for alcohol; a multi-drug hair test; and various lab and
instant urine tests.

Costs of the kits ranged from $2.75 for a single alcohol test to $89 for a
multi-drug screen.

Most of the product sites gave conflicting or incomplete information about
which drugs might be detected by the products being sold.

"Drug testing just isn't like other home medical tests that people use so
widely today," Levy said. "It's very complicated, and you have to know what
you're looking for and how to interpret the results. You can think you're
covering all the bases, and not test for what your child actually turns out
to be using."

Even if a parent does select the right kit, "there are windows of
opportunity for testing depending on the substance," Levy said. "Most have
to be done within 24 to 48 hours of use. So if the test comes back negative
for cocaine, it just means it has been that long since the teen used it,
not necessarily that they don't have a problem with cocaine."

Lab protocols for drug testing are "technically challenging, even for
medical professionals," the doctor said, involving bathrooms with no
running water or even direct observation of sample collection, "neither one
of which is really an option at home."

Tests performed at home tend to have higher error rates, and many parents
may not understand that different drug screens have different error rates.

One product advertised on the Web had false negative rates of 6 percent to
40 percent, depending on the type of drug being tested for.

"False positives are also a problem, as in the case of amphetamines,
especially if the child is using high doses of caffeine or cold medications
using high doses of pseudoephedrine or theophylline," Levy said.

"Similarly, the stories about poppy seeds in bagels and other foods are
true, if the sensitivity threshold of a test is set low enough," she added.

And as far as beating the test, just drinking a lot of fluids beforehand or
adding water to a urine sample can throw off most of the tests reviewed,
Levy said.

She said just having a parent demand that a child take a home drug test may
undermine their relationship, be seen as invasive and a violation of
adolescent rights. "It's better to put a professional in between the parent
and the child in those situations."

Only one of the eight product sites Levy reviewed offered any advice on
testing a child against his or her will, while only half recommended that
parents consult a medical professional if test results were positive.

Levy also found that many of the claims of benefits of home drug testing
made by the Web sites were "unsubstantiated" by any scientific evidence.

The Substance Abuse Policy Research Program of the Robert Wood Johnson
Foundation funded the study.