The following is a modified excerpt from Applied Qualitative Research Design: A Total Quality Framework Approach (Roller & Lavrakas, 2015, pp. 54-55), a qualitative methods text discussing a quality approach to in-depth interviews, focus group discussions, ethnography, qualitative content analysis, case study, and narrative research.

The in-depth interview (IDI) method has been the method of choice for various purposes across the health care and social sciences. Compared to focus group discussions, IDIs enable a thorough examination of a topic unencumbered by social pressure or influence from a group of individuals. This freedom to speak candidly has made individual interviews (i.e., IDIs) the preferred method for investigating complex, sensitive, and unexplored topics. Whether it is a study concerning the perceptions and behaviors associated with caring for a spouse with early-onset Alzheimer’s disease, environmental hazards, contraception use among urban adolescents, the communication needs among cancer patients, the teaching of children with autism, consumer preference for one product brand over another, or the usability of a company’s website, an IDI approach provides the researcher with a distinct opportunity to try to unravel the experiences and thoughts of an individual that led to particular needs, motivations, and behavior.

In-depth interviews can be particularly effective when the subject matter is sensitive and/or the target population is not easily accessible. This is why, for example, the IDI method is well suited for health and health-care-related issues, such as the attitudes and ways of coping among cancer survivors, patients, and their caregivers.³ The IDI method is often the preferred approach over group discussions for these types of studies, given that (a) people may be more likely to participate in a one-on-one study due to the delicate nature of the research topic (e.g., asking about patients’ experiences with cancer treatment); (b) the particular sensitivity required of the researcher with hard-to-reach and/or vulnerable populations (e.g., people who are physically and emotional affected by their cancer treatment); and (c) the need for a “safe” context or environment that fosters a meaningful conversation about the interviewees’ personal experiences related to the disease. For these reasons, researchers in the medical field have successfully used the qualitative IDI method to examine not only patients’ responses to cancer and its treatments but to a variety of other physical and mental health issues.⁴

The IDI method is also highly relevant to, and widely used in, the social sciences. Researchers in the following, and other social science disciplines, benefit greatly from the one-on-one approach of the IDI research method:

• Education (e.g., to explore school leadership, policy reforms, teaching practices, or minority student issues).
• Psychology (e.g., to understand coping strategies among women who have survived childhood sexual abuse, the emotional effects following a natural disaster, and age-related memory function).
• Communication (e.g., to investigate attitudes toward negative political advertising on television, the impact of magazine content on consumer behavior, online communication networks, and audience perceptions of information bias).
• Social work (e.g., to understand the barriers in disclosing domestic violence, the educational needs within a child welfare program, and the effect of cultural programs on parental well-being).
• Marketing (e.g., to examine shopping preferences among consumers, the corporate financial services needs among executives, the viability of new product lines, the usability of a newly designed retail website, and the effectiveness of communication strategies).

3. There are many examples of IDI studies among cancer survivors, patients, and caregivers, including Leydon et al., 2000; Mancini et al., 2011; Murray et al., 2002; Johansson et al., 2003; Osse et al., 2002.

4. There are many examples of using the IDI method to examine health-related issues outside of those pertaining to cancer: for example, Mollen et al., 2008; Wahl, Gjengedal, & Hanestad, 2002; Veseth, Binder, Borg, & Davidson, 2012; Karp & Tanarugsachock, 2000; Provoost et al., 2010.

Johansson, K., Holmström, H., Nilsson, I., Ingvar, C., Albertsson, M., & Ekdahl, C. (2003). Breast cancer patients’ experiences of lymphoedema. Scandinavian Journal of Caring Sciences, 17(1), 35–42. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/12581293

Karp, D. A., & Tanarugsachock, V. (2000). Mental illness, caregiving, and emotion management. Qualitative Health Research, 10(1), 6–25. https://doi.org/10.1177/104973200129118219

Leydon, G. M., Boulton, M., Moynihan, C., Jones, A., Mossman, J., Boudioni, M., & McPherson, K. (2000). Cancer patients’ information needs and information seeking behaviour: In-depth interview study. BMJ, 320(7239), 909–913. Retrieved from http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=27332&tool=pmcentrez&rendertype=abstract

Mancini, J., Baumstarck-Barrau, K., Simeoni, M.-C., Grob, J.-J., Michel, G., Tarpin, C., … Auquier, P. (2011). Quality of life in a heterogeneous sample of caregivers of cancer patients: An in-depth interview study. European Journal of Cancer Care, 20(4), 483–492. https://doi.org/10.1111/j.1365-2354.2010.01227.x

Mollen, C. J., Barg, F. K., Hayes, K. L., Gotcsik, M., Blades, N. M., & Schwarz, D. F. (2008). Assessing attitudes about emergency contraception among urban, minority adolescent girls: An in-depth interview study. Pediatrics, 122(2), e395–e401. https://doi.org/10.1542/peds.2008-0009

Murray, S. A., Boyd, K., Kendall, M., Worth, A., Benton, T. F., & Clausen, H. (2002). Dying of lung cancer or cardiac failure: Prospective qualitative interview study of patients and their carers in the community. British Medical Journal, 325(7370), 929.

Osse, B. H. P., Vernooij-Dassen, M. J. F. J., Schadé, E., de Vree, B., van den Muijsenbergh, M. E. T. C., & Grol, R. P. T. M. (2002). Problems to discuss with cancer patients in palliative care: A comprehensive approach. Patient Education and Counseling, 47(3), 195–204. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/12088597

Provoost, V., Pennings, G., De Sutter, P., Gerris, J., Van de Velde, A., & Dhont, M. (2010). Patients’ conceptualization of cryopreserved embryos used in their fertility treatment. Human Reproduction, 25(3), 705–713. https://doi.org/10.1093/humrep/dep387

Veseth, M., Binder, P.-E., Borg, M., & Davidson, L. (2012). Toward caring for oneself in a life of intense ups and downs: A reflexive-collaborative exploration of recovery in bipolar disorder. Qualitative Health Research, 22(1), 119–133. https://doi.org/10.1177/1049732311411487

Wahl, A. K., Gjengedal, E., & Hanestad, B. R. (2002). The bodily suffering of living with severe psoriasis: In-depth interviews with 22 hospitalized patients with psoriasis. Qualitative Health Research, 12(2), 250–261. https://doi.org/10.1177/104973202129119874