Qualitative Interviewing: Testing Health Surveys Among Vietnam War Veterans at the Age of 70 Years

The Vietnam Era Health Retrospective Observational Study (VE-HEROeS) is a nationwide study designed to compare the health of U.S. Vietnam era veterans to age- and sex-matched U.S. residents. Two self-administered mail questionnaires, one for veterans and the other for the U.S. nonmilitary population, were developed using already validated and newly developed items. A pretest was conducted to evaluate item recall and comprehension, new-item response validity, and the overall survey experience (usability of survey materials including the screener questionnaire for nonveterans). Subject recruitment was completed using convenience sampling and a $50 incentive. Cognitive interviewing and usability interviewing, two qualitative research methods, were implemented. Interviews were conducted in two stages (Stage 1, cognitive interviewing, n = 12; Stage 2, usability testing, n = 8) by three experienced methodologists. Concurrent probing techniques, unscripted probes, and retroactive probing were used to elicit response from 14 veterans and six nonveterans (mostly male, White, and aged 65-70 years). Information about the overall survey process was also obtained through observation during usability testing. Results signify that qualitative research is an important part of questionnaire development targeting older veterans due to issues involving comprehension, interpretability, and recall.