Smokers' reports of quitting need bio-verification

A VA study found that one in five respondents who reported quitting smoking was actually still using tobacco-according to urine tests turned in by the respondents. The researchers urge routine use of bio-verification in smoking-cessation studies. (Photo: Science Photo Library/Getty)

Smoke screen—A VA study found that one in five respondents who reported quitting smoking was actually still using tobacco—according to urine tests turned in by the respondents. The researchers urge routine use of bio-verification in smoking-cessation studies. (Photo: Science Photo Library/Getty)

Most smoking-cessation studies use urine tests or other lab measures to verify quit rates. But the tests are not always practical or cost-effective. Can researchers rely only on smokers' self-reports, or will they arrive at skewed results that way?

The question has been studied in various populations, but seldom in VA. A new analysis provides guidance for VA researchers.

The analysis was part of a larger study of the Tobacco Tactics smoking-cessation program used in VA.

The new study included nearly 600 Veterans who had taken part in Tobacco Tactics. Six months after the program ended, they were asked to fill out surveys and return urine strips.

Urine tests that measure cotinine—a byproduct of nicotine—are considered the gold standard in biochemical verification of tobacco use or abstinence. The test can show traces of tobacco use up to a few days later.

About one in five Veterans who reported quitting cigarettes was probably not giving an accurate account, according to the urine results. The 21-percent "misclassification" rate in the study was high compared with findings from other smoking-cessation research that compared self-reports versus lab tests in various populations. Research suggests that groups that feel more pressured to quit—for example, those who have lung or heart disease and are under doctors' close supervision—are more likely to misrepresent their smoking status.

The study authors, from the Ann Arbor VA Medical Center, say that notwithstanding the added costs of bio-verification, and the extra burden on study participants, the tests are"helpful in determining true quite rates in VA smoking cessation studies" and should be used routinely.

(Addictive Behaviors, March 2013)