Article by Anca Romantan, Robert Hornik, Judith Weiner, Vincent Price, Joseph Cappella, and K. Viswanath in the journal Measures of Exposure (2008).
This paper considers several approaches to survey measurement of incidental exposure to the mass media relevant to cancer communication. HINTS I assessed health media exposure by measures of ‘attention’ and of general media use. Unsure about the best exposure measures to be used in cancer-related survey research, we carried out a study comparing alternative exposure questions to inform the construction of the HINTS II instrument. A nationally representative telephone survey included 800 respondents. We compared measures addressing: general media exposure, exposure to health media, attention to health topics, quantity of health information, general and specific cancer exposure assessed by closed- and by open-ended questions. Controlling for education, gender and age, the strongest predictor of cancer knowledge was the open-ended measure about cancer prevention (9.8%), followed by open-ended measures about diet and exercise and the parallel closed-ended questions (6.7%), attention to health topics (6.2%), quantity of health information (4.1%), and health media exposure (3.7%). General media exposure was not associated with cancer knowledge, although it predicted knowledge about noncancer health issues salient in the media. There may be some bias in using knowledge to validate open-ended exposure measures; their utility might be exaggerated here. We propose that the closed-ended specific questions may be just as useful. Despite its good predictive power, attention may be confounded with involvement.