Individual in-depth interviews have the advantage of allowing for extensive probes of structured responses, and eliciting confidential information that might be problematic in a group format. An important difference between in-depth interviews and structured individual surveys is the use of open-ended questions. When conducted properly, interviews should provide study participants with the opportunity to determine the most appropriate response to a question, and allow for the collection and exploration of unexpected or emergent findings. These interviews can be readily biased by over-zealous interviewers employing close-ended questions, or probes.
Individual interviews can be conducted in community settings, such as heavily trafficked locales, including shopping centers, movie theaters, hospitals, or other pedestrian high-traffic areas in a metropolitan city or rural county. One common form of individual interviews are intercept interviews, in which people who possess the characteristics of the target audience for the health promotion program, for example, women of a certain racial, ethnic, or age group, are recruited on the spot for short, two- to five-minute interviews. Formal in-depth interviews require more time than intercept interviews, but can also be scheduled to take place in community settings where participants are comfortable and are thus more likely to provide contextual details important to a program evaluation. In both strategies, key questions may concern the person’s familiarity with a health problem, knowledge of the availability of the program and its purpose, or interest in a special program. Probing questions might consist of queries into the source of knowledge or the basis for perceptions about or interest in a program.