Nondirective interview or, to use the full term, an in-depth nondirective interview is a research technique known among researchers as IDI (Individual In-depth Interview). It is good to precede the short description of this method with a general statement that illustrates the possibilities of its applications. Qualitative methods (including nondirective interview) allow, as Graham Gibbs writes, to take a closer look at the outside world, as well as to describe, interpret, and sometimes explain social phenomena from an internal perspective (G. Gibbs, „Analyzing Qualitative Data”, Warsaw 2011). There is quite a clear suggestion in this statement about the nature of the qualitative data. They are supposed to enable the researcher, figuratively speaking, to penetrate the world of the examined person. The answer to the question of how to do this lies in the nature of the interviewer-respondent relations.

In the literature on the interview technique, the term „conversation” often appears as a synonym for it. However, we should treat it metaphorically. More precisely, it is rather asymmetrical interpersonal communication. We are dealing with a situation with clearly defined roles – one person asks only questions, while the other only answers them. If, however, to remain in the convention of an interview as a conversation, it can be said, bearing in mind the aforementioned limitation, that it is an uncontrolled conversation. The respondent says what they want and how they want it. They use their own phrases to express their thoughts. Although the questions asked for them impose thematic limitations, there’re no suggested ready-made variants of answers from which they only have to make choices. Moreover, the interviewer adjusts both the content of the questions and the order in which they are asked to the specific research situation. This makes it possible to create a fairly natural interview situation. 
Each in-depth nondirective interview is structured to some extent, as it is an implementation of the plan prepared by the researcher. It’s the intention of the researcher that leads to the achievement of the intended goal. This goal is, of course, information on a specific topic. The plan is usually specified by means of instructions, i.e. guidelines specifying the scope of the sought information. They can be formulated at various levels of generality – from specific to very general. Importantly, they aren’t questions, but declarative sentences, usually beginning with words such as „determine”, „define”, etc. The point is, of course, not to impose ready-made question phrases on the interviewer, but to formulate them according to the respondent and the specific situation in which they are. For the sake of illustration, we will use such an example. So let’s say a researcher wants to get information about a product. They assumed that the IDI study would take into account three dimensions: price, quality, and product availability. They also decided to introduce a comparative perspective in their study, assuming that none of the products function in a vacuum, but are surrounded by other products of the same class. Therefore, they concretized their research need in the form of three dispositions:

1. Establish the respondents’ opinions on the price of the product in comparison with other similar products (can give their names);
2. Establish product quality reviews in comparison with…
3. Establish the respondents’ opinions on the availability of the product in comparison with …

Of course, you can come across situations in which the researcher makes further instances. To refer to our example, it would consist in further extension of each of these three dispositions. That is, indicating to the interviewers the need to obtain more detailed information about each of these three areas. You may also encounter a different strategy. It consists of minimally structuring the interview, i.e. indicating to the interviewers only the topic of the conversation, without introducing any additional suggestions (establishing the respondents’ opinions about product X in comparison with other products of the same class).

It’s also worth remembering that a nondirective interview doesn’t have to consist of just asking questions. It’s possible to imagine a situation when, during its duration, additional research techniques are used, such as tests and techniques typical of focus studies (e.g. Chinese portrait). Although we haven’t encountered such cases in research practice, it seems to be fully legitimate. With the use of each qualitative technique, we strive for the fullest possible knowledge of the opinions of the respondents, and the selection of measures that are to enable this depends only on the imagination of the researcher.

As each IDI is recorded, it’s necessary to transcribe the recording before processing the material. It’s the basis for further analytical work.

The result of developing the materials is a report which, in short, is a summary of the study taking into account the instructions formulated by the researcher.

In-depth nondirective interview (IDI) is a technique that has become a permanent fixture in the UX environment. This is due to the freedom it gives and the possibility of adapting the method to the process of testing, for instance, user paths in prototypes of applications or systems. When using this method, as with any of the quantitative methods, the researcher should take into account all the limitations related to the projection of its results on the recipient population. Therefore, dear Reader, if you have not yet had the opportunity to read my post, which covered this topic, I heartily encourage you to do so.