Cognitive testing of tobacco use items for administration to patients with cancer and cancer survivors in clinical research

BACKGROUND To the authors' knowledge, there are currently no standardized measures of tobacco use and secondhand smoke exposure in patients diagnosed with cancer, and this gap hinders the conduct of studies examining the impact of tobacco on cancer treatment outcomes. The objective of the current study was to evaluate and refine questionnaire items proposed by an expert task force to assess tobacco use. METHODS Trained interviewers conducted cognitive testing with cancer patients aged ≥21 years with a history of tobacco use and a cancer diagnosis of any stage and organ site who were recruited at the National Institutes of Health Clinical Center in Bethesda, Maryland. Iterative rounds of testing and item modification were conducted to identify and resolve cognitive issues (comprehension, memory retrieval, decision/judgment, and response mapping) and instrument navigation issues until no items warranted further significant modification. RESULTS Thirty participants (6 current cigarette smokers, 1 current cigar smoker, and 23 former cigarette smokers) were enrolled from September 2014 to February 2015. The majority of items functioned well. However, qualitative testing identified wording ambiguities related to cancer diagnosis and treatment trajectory, such as "treatment" and "surgery"; difficulties with lifetime recall; errors in estimating quantities; and difficulties with instrument navigation. Revisions to item wording, format, order, response options, and instructions resulted in a questionnaire that demonstrated navigational ease as well as good question comprehension and response accuracy. CONCLUSIONS The Cancer Patient Tobacco Use Questionnaire (C-TUQ) can be used as a standardized item set to accelerate the investigation of tobacco use in the cancer setting.