Using Cognitive Interviewing to Better Assess Young Adult E-cigarette Use.

INTRODUCTION: Characteristics of electronic nicotine delivery systems (ENDS) make assessment of their use a challenge for researchers. Cognitive interviews are a way of gaining insight into participants' interpretations of survey questions and the methods they use in answering them, to improve survey tools.
METHODS: We used cognitive interviews to modify a young adult survey and improve assessment of quantity and frequency of ENDS use, as well as reasons for initiation and use of ENDS products. Twenty-five college students between the ages of 18 and 32 participated in individual cognitive interviews, which assessed question comprehension, answer estimation, retrieval processes, and answer response processes.
RESULTS: Comprehension issues arose discerning between ENDS device types (eg, cigalikes vs. vape pens), and answer estimation issues arose regarding ENDS use as drug delivery systems. These issues appeared to improve when pictures were added specifying the device in question, as well as when specific language naming nicotine as the ENDS product content was added to survey questions. Regarding answer retrieval, this sample of users had problems reporting their frequency of ENDS use, as well as quantifying the amount of ENDS products consumed (eg, volume of e-juice, number of cartridges, nicotine concentration).
CONCLUSIONS: Accurate assessment of ENDS products proved challenging, but cognitive interviews provided valuable insight into survey interpretation that was otherwise inaccessible to researchers. Future research that explores how to assess the wide array of ENDS devices, as well as possible population differences among specific device-type users would be valuable to public health researchers and professionals. IMPLICATIONS: This study extends the current literature by using cognitive interviews to test ENDS assessment questions in a sample of young adults, a population at elevated risk for ENDS use. Problems encountered when answering ENDS use questions underscore the need to develop easily understood ENDS questions that allow for quantification of ENDS use. Future research examining the nature of ENDS product types and different levels of user experience will yield valuable assessment tools for researchers and tobacco control professionals.