Semi-structured interviews are based on an interview guide. This is a set of clear instructions comprising a list of questions that should be asked and topics that should be covered in the interview. [Box 1](#BOX1], for example, shows an interview guide for use early in a SQUEAC investigation with carers of children in the program.
The exact order and wording of questions may differ from informant to informant and is likely to change as data collection proceeds and the focus of the data-collection effort changes. The interviewer does not have to stick strictly to the questions in the interview guide and may follow ‘leads’ and new topics as they arise in the course of an interview, although all questions and topics outlined in the interview guide should be covered in each interview.
The use of an interview guide helps the interviewer make efficient use of the time available for an interview. This is important when interviewing informants that may not be able or willing to spend a lot of time in an open-ended discussion with the interviewer.
The structure imposed on the interview by the interview guide shows the informant that you are clear about what you want from the interview. This is important when dealing with, for example, clinic staff and government officials.
The flexibility of being able to investigate new ‘leads’ introduced by the informant sets this method apart from simple structured interviews.
Target respondent or source
Semi-structured interviews are conducted with key informants such as:
Community-based informants such as schoolteachers, traditional healers, traditional birth attendants (TBAs), health extension workers, agriculture extension workers, and CBVs
Carers of children in the program
Carers of non-covered, defaulting, and DNA cases
Type of investigation
Two types of semi-structured interview have proved useful in SQUEAC investigations:
Focussed interviews (in-depth interviews). Focussed interviews are used to intensively investigate a single topic. The purpose of a focused interview is to gain a complete and detailed understanding of the topic under investigation. Focussed interviews are very useful toward the end of the data-collection effort to resolve discrepancies in previously collected data or when collecting data from informants with an in-depth knowledge about a single topic (e.g., asking outreach workers, CHWs, and CBVs about probable reasons for non-attendance and defaulting).
Case histories (case studies). A case history is similar to history-taking in clinical medicine, except that the emphasis of the history is less on eliciting a history of symptoms (although this is useful for identifying mismatches between program and community aetiologies/definitions of malnutrition as in Box 1) and more on eliciting the context to a specific situation. Case histories are most useful when you need to understand a situation in depth and when information-rich cases (e.g., carers of defaulting and DNA cases) can be found.