Background: The viewpoint and special needs of individuals with severe mental illness is crucial in development of mental health nursing. In-depth knowledge of the perspectives of people with severe mental illness is primarily established in dialog with individuals experienced in the phenomenon investigated. To reach trustworthiness of findings in qualitative studies is central and the interview approach used should assure trustworthiness in data collection regarding perspectives of the individual essential in developing nursing research and practice.

Aim: The aim of the paper was to describe and discuss methodological issues related to research interviews involving people with severe and persistent mental illness.

Method: Five qualitative interview studies regarding experiences of different aspects of life among people with severe mental illness were reflected and discussed regarding methodological issues related to the interview situation involving people with severe and persistent mental illness (N=51).

Results: The discussions forming the results revealed three crucial topics in qualitative interview studies with individuals with severe mental illness. Use previous experiences of interactions with persons with mental disabilities with an open mind without prejudices. Balance the interviewee’s need of support and encouragement during the interview without manipulating contents of statements. Comprehend the essential meaning in the interviewee’s statements even when statements are short and narrow.

Discussion: Three crucial topics in qualitative interview studies with individuals with severe mental illness were revealed. Further studies regarding sampling procedures and analysis of collected data are needed to ensure trustworthiness of findings regarding interviews involving people with severe mental illness.