What can interest tell us about uptake of genetic testing? Intention and behavior amongst smokers related to patients with lung cancer

Background: Much of the research examining psychosocial aspects of genetic testing has used hypothetical scenarios, based on the largely untested assumption that hypothetical genetic testing intentions are good proxies for behavior. We tested whether hypothetical interest predicts uptake of genetic testing and whether factors that predict interest also predict uptake.

Methods: Participants (n = 116) were smokers and related to patients with lung cancer, who completed a telephone survey. Interest in genetic testing for lung cancer risk was indicated by responding 'definitely would' to a Likert-style question. Internet-delivered genetic testing for lung cancer risk was then offered. Uptake was indicated by requesting the test and receiving the result.

Results: 63% of participants said they 'definitely would' take the genetic test; uptake was 38%. Participants who said they 'definitely would' take the test were more likely than others to take the offered test (45% vs. 26%, p = 0.035). Interest was associated with attitudes towards genetic testing and motivation to quit smoking. Uptake was associated with motivation, prior awareness of genetic testing, and daily Internet use.

Conclusion: Hypothetical interest only modestly predicts uptake of genetic testing. Interest in genetic testing likely reflects generally positive attitudes that are not good predictors of the choices individuals subsequently make.