Advantages and Disadvantages of Different Types of Interview Structure
As we saw in section 1 above, research interviews can vary a great deal in their level of structure. The level of structure also has a major influence on the kind of data collected. Highly structured interviews can collect a lot of quantifiable data and can work well in situations where you cannot record the interview in full. However, by focussing on lots of structured questions you may not have the chance to really explore what the interviewee wants to tell you. Less structured interviews work well when you want to give the interviewee the chance to talk and collect primarily qualitative data, but you really need to record such interviews.
A Key Comparison between Structured and Less Structured In-depth interviews is that:
Structured Interviews Emphasise Reliability - How accurately different respondents' answers can be compared
Less Structured, In-Depth Interviews Emphasise Validity - How close answers get to the respondents' real views (Langley, 1987, p. 24).
The following table provides an overview of the key advantages and disadvantages of different types of interview.
Advantages and Disadvantages of Structured and In-Depth Interviews
An important advantage of research interviews is their adaptability. A skilled interviewer can (to varying degrees, depending on the type and purpose of an interview) follow up the thoughts, feelings and ideas behind the responses given, in a way that questionnaire completion cannot capture. Having got access to a person or group of people to interview, you are guaranteed some sort of response (this is in comparison to relying on people's willingness to complete and return a postal or on-line questionnaire, for example). Questionnaire responses have to be taken at face value, whereas responses to interview questions can be clarified and expanded on the spot. Validated structured questionnaires (that is, questionnaires that have already been used and shown to measure what they say they do), which can also be administered as part of an interview, are highly respected for their reliability. Less structured and in-depth interviews allow for more exploration and understanding of responses (they are more likely to elicit valid responses). With a skilled interviewer more open and honest answers can be forthcoming in unstructured interviews, in comparison with structured interviews or postal questionnaires. Structured interviews are generally easier to analyse than in-depth and unstructured interviews.
The most obvious disadvantage of conducting any type of research interview is that they are time consuming, particularly if they are recorded and fully transcribed (ie word for word). As with the advantages of conducting research interviews, disadvantages vary with the type of interview. Structured interviews inevitably limit responses and the data obtained may not be reliable if there are faults in the way questions are asked or understood by the respondent. Structured interviews can be very limiting in terms of allowing any real exploration or understanding of the responses given. In highly structured interviews the key differences, in comparison with postal questionnaire completion by the respondent, are that the researcher can explain questions that the respondent does not understand, or provide prompts to help the respondent answer the question. Consistent prompts are agreed beforehand. The sample size for in-depth and unstructured interviews is generally small and may not be representative of a particular population. Some would argue that it can be difficult to compare the results of in-depth and unstructured interviews in that they may be very specific to a particular interaction (the research interview itself).
In practice many interviews are neither completely structured nor completely in-depth, but somewhere between the two.
Developing an Interview Schedule
Go to the Research Methods Hub and explore the section on Research Interviews in 'Research using primary data', in particular read the sections on 'Developing an Interview Schedule' and look at the example.
Have a go at drafting an interview schedule on a topic that interests you.
Would you record your interview? Would you fully transcribe it?
Estimate the time costs of conducting a one hour recorded and fully transcribed (word-for-word) interview, with a professional located 30 minutes drive from your home or workplace.