Why is this tool used in evaluation?

The interview is an information collection tool which usually takes the shape of a face-to-face discussion between the evaluator and the interviewee. In evaluation, the use of interviews is simple, quick, and affordable, which makes its use inevitable.

Figure 1: Example of the interview's role in evaluation

What use can be made of the interview?

In evaluation, the interview collects different kind of information:

  • Facts and information for the verification of facts
  • Opinions and perspectives
  • Analyses
  • Suggestions
  • Reactions to the evaluator's hypotheses and conclusions

The interview may be used as a quantitative collection tool; however, it is mostly a qualitative device. Information, including facts that can be checked, points of view, analyses and opinions should be clearly distinguished. Three types of interviews can be carried out:

Unstructured interviews
The interviewee expresses himself/herself freely and can discuss unplanned topics, because there is no predetermined set of questions. The evaluator intervenes only to generate and develop questions relating to the interviewee's comments.

This type of interview is particularly interesting at the start of an evaluation, in order to get a global view of the subject, and identify the major topics and issues.

Semi-structured interviews
This type of interviews collects the respondents' testimonies using an interview guideline (flexible framework of topics derived from the evaluation questions). The evaluator modifies the interview guide's instructions with additional questions, in order to develop useful areas of inquiry during the interview.

This type of interview is the most frequently used, particularly when the evaluator knows sufficient about the aims and the main questions to pose during the evaluation.

Structured interviews
The evaluator follows strictly the interview guideline instructions. He/She asks different interviewees the same set of questions and the interviewee is not given the opportunity to express himself/herself freely. The evaluator avoids generating and developing additional questions. Answers to each question tend to be short.

This type of interview is useful when a large number of interviews must be carried out and when the evaluator wants to minimise the risk of bias from the interviewer.

Establish homogeneous interview grids when several teams are responsible for conducting the interviews. Semi-structured interviews are the most commonly used tool in evaluation and are the subject of further guidance.

How is the interview carried out?

How is the interview prepared?

The evaluator should first prepare the list of questions to be asked during the interviews.

The schedule of questions indicates the categories of respondent to be interviewed, within which the evaluator chooses those most capable of providing the information. The evaluator must determine:

  • The real beneficiaries of the policy implemented
  • The people who have played a strategic role
  • The people concerned with programme implementation
  • The people who might have been behind the programme's limitations or unscheduled impacts (such as actors with diverging interests, intervening during the programme's operation, or target groups of the policy or the programme)

Once the categories of respondent are defined, the evaluator can schedule the interviews and try to find a balance between the rational and optimal use of his/her own time and a flexible and "human" vision of the other's time.

Questionnaire grids (the evaluation's strategic questions), and interview guidelines derived from them (questions asked during the interview), vary with the categories of respondent, the latter's links with the evaluated issue and the type of interview (unstructured, semi-structured or structured interviews).

Grids should include all themes and questions which the evaluator wants to discuss with the respondents. The questionnaire grid is an intermediary between the evaluation study's design and its implementation

Interview guidelines provide the interview with a framework which is not binding on the evaluator.

How is the interview conducted?

Stage 1: Establish a rapport

  • To be aware of and respect local habits and customs
  • To anticipate any language difficulties
  • To explain the purpose of the interview
  • To establish the rules, such as the interview's length, the recording of the interview and anonymity

Stage 2: Adjust the respondent's answers to the interview subject

  • The evaluator must adjust to his interlocutor's role and hierarchical rank in the institution and be aware of the specificities of the respondent's answers
  • The evaluator must be flexible while controlling the interview's progress

Stage 3: follow the interview guide and deepen the questioning

  • Show reactivity through the use of contradiction, notification, etc.
  • Make direct observations during the interview, even when it is not planned in the interview guideline

Stage 4: conclude the interview

  • Keep track of all the information: the evaluator should read his notes shortly after the interview, structure them and add, if necessary, non-verbal details
  • Protect the confidentiality of the interview
  • If necessary, validate the content of the interview report with the respondent

What are the preconditions for its use?

Figure 2: the preconditions for its use
The time span The preparation for the interview does not take long.

The number of interviews which can be carried out during the day is limited. In practice, at the interviewee's request, the expert may conduct an interview with several respondents at the same time. This particular use of the interview increases the opportunity of collecting the information required in a relatively short time.

Human resources Interviews must be conducted by a trained professional. The necessary skills are:

  • Thorough knowledge of the major topics and issues addressed in the evaluation
  • Excellent interviewing skills (ability to listen and maintain the momentum of the interview, to be reactive and get to the point quickly, to control the course of the interview)
  • The ability to quickly understand the respondent's perspective in order to be interactive
Financial resources Possible transportation costs

Costs depend on the number of interviews; however, the interview itself does not lead to substantial costs

What are the advantages and limitations of the tool?

Figure 3: The advantages and limitations of the tool
Advantages Quick and easy to use.

Short delays and low costs.

Appropriate tool to meet a limited number of key respondents.

Essential tool to develop analyses and understand the stakeholders' perceptions of the programme.

Limitations At a reasonable cost, only few people can be interviewed.

Problems relating to the respondent's 'representativeness' particularly for social groups and beneficiaries.

The information must be checked and interviews are generally combined with other analytical tools.


Former Capacity4dev Member
last update
7 December 2022

More actions