Types of Interviews in Research and Methods

There’s more types of interviews than most people think. An interview is generally a qualitative research technique which involves asking open-ended questions to converse with respondents and collect elicit data about a subject. The interviewer in most cases is the subject matter expert who intends to understand respondent opinions in a well-planned and executed series of questions and answers. Interviews are similar to focus groups and surveys when it comes to garnering information from the target market but are entirely different in their operation – focus groups are restricted to a small group of 6-10 individuals whereas surveys are quantitative in nature. Interviews are conducted with a sample from a population and the key characteristic they exhibit is their conversational tone.

Fundamental Types of Interviews in Research

A researcher has to conduct interviews with a group of participants at a juncture in the research where information can only be obtained by meeting and personally connecting with a section of their target audience. Interviews offer the researchers with a platform to prompt their participants and obtain inputs in the desired detail. There are three fundamental types of interviews in research:

  • Structured Interviews:

Structured interviews are defined as research tools that are extremely rigid in their operations are allows very little or no scope of prompting the participants to obtain and analyze results. It is thus also known as a standardized interview and is significantly quantitative in its approach. Questions in this interview are pre-decided according to the required detail of information.

Structured interviews are excessively used in survey research with the intention of maintaining uniformity throughout all the interview sessions.

They can be closed-ended as well as open-ended – according to the type of target population. Closed-ended questions can be included to understand user preferences from a collection of answer options whereas open-ended can be included to gain details about a particular section in the interview.

Advantages of structured interviews:

  • Structured interviews focus on the accuracy of different responses due to which extremely organized data can be collected. Different respondents have different type of answers to the same structure of questions – answers obtained can be collectively analyzed.
  • They can be used to get in touch with a large sample of the target population.
  • The interview procedure is made easy due to the standardization offered by structured interviews.
  • Replication across multiple samples becomes easy due to the same structure of interview.
  • As the scope of detail is already considered while designing the interview, better information can be obtained and the researcher can analyze the research problem in a comprehensive manner by asking accurate research questions.
  • Since the structure of the interview is fixed, it often generates reliable results and is quick to execute.
  • The relationship between the researcher and the respondent is not formal due to which the researcher can clearly understand the margin of error in case the respondent either degrees to be a part of the survey or is just not interested in providing the right information.

Disadvantages of structured interviews:

  • Limited scope of assessment of obtained results.
  • The accuracy of information overpowers the detail of information.
  • Respondents are forced to select from the provided answer options.
  • The researcher is expected to always adhere to the list of decided questions irrespective of how interesting the conversation is turning out to be with the participants.
  • A significant amount of time is required for a structured interview.  

Learn more: Market Research

  • Semi-Structured Interviews:

Semi-structured interviews offer a considerable amount of leeway to the researcher to probe the respondents along with maintaining basic interview structure. Even if it is a guided conversation between researchers and interviewees – an appreciable flexibility is offered to the researchers. A researcher can be assured that multiple interview rounds will not be required in the presence of structure in this type of research interview.

Keeping the structure in mind, the researcher can follow any idea or take creative advantage of the entire interview. Additional respondent probing is always necessary to garner information for a research study. The best application of semi-structured interview is when the researcher doesn’t have time to conduct research and requires detailed information about the topic.

Advantages of semi-structured interviews:

  • Questions of semi-structured interviews are prepared before the scheduled interview which provides the researcher with time to prepare and analyze the questions.
  • It is flexible to an extent while maintaining the research guidelines.
  • Researchers can express the interview questions in the format they prefer, unlike the structured interview.
  • Reliable qualitative data can be collected via these interviews.
  • Flexible structure of the interview.

Learn more: Quantitative Data

Disadvantages of semi-structured interviews:

    • Participants may question the reliability factor of these interviews due to the flexibility offered.
    • Comparing two different answers becomes difficult as the guideline for conducting interviews is not entirely followed. No two questions will have the exact same structure and the result will be an inability to compare are infer results.   
  • Unstructured Interviews:

Also called as in-depth interviews, unstructured interviews are usually described as conversations held with a purpose in mind – to gather data about the research study. These interviews have the least number of questions as they lean more towards a normal conversation but with an underlying subject.

The main objective of most researchers using unstructured interviews is to build a bond with the respondents due to which there are high chances that the respondents will be 100% truthful with their answers. There are no guidelines for the researchers to follow and so, they can approach the participants in any ethical manner to gain as much information as they possibly can for their research topic.

Since there are no guidelines for these interviews, a researcher is expected to keep their approach in check so that the respondents do not sway away from the main research motive. For a researcher to obtain the desired outcome, he/she must keep the following factors in mind:

  • Intent of the interview.
  • The interview should primarily take into consideration the participant’s interest and skills.
  • All the conversations should be conducted within permissible limits of research and the researcher should try and stick by these limits.
  • The skills and knowledge of the researcher should match the purpose of the interview.
  • Researchers should understand the do’s and don’ts of unstructured interviews.

Advantages of Unstructured Interviews:

  • Due to the informal nature of unstructured interviews – it becomes extremely easy for researchers to try and develop a friendly rapport with the participants. This leads to gaining insights in extreme detail without much conscious effort.
  • The participants can clarify all their doubts about the questions and the researcher can take each opportunity to explain his/her intention for better answers.
  • There are no questions which the researcher has to abide by and this usually increases the flexibility of the entire research process.

Disadvantages of Unstructured Interviews:

  • As there is no structure to the interview process, researchers take time to execute these interviews.
  • The absence of a standardized set of questions and guidelines indicates that the reliability of unstructured interviews is questionable.
  • In many cases, the ethics involved in these interviews are considered borderline upsetting.

Learn more: Qualitative Market Research

Methods of Research Interviews:

There are three methods to conduct research interviews, each of which is peculiar in its application and can be used according to the research study requirement.

Personal Interviews:

Personal interviews are one of the most used types of interviews, where the questions are asked personally directly to the respondent. For this, a researcher can have a guide online surveys to take note of the answers. A researcher can design his/her survey in such a way that they take notes of the comments or points of view that stands out from the interviewee.


  • Higher response rate.
  • When the interviewees and respondents are face-to-face, there is a way to adapt the questions if this is not understood.
  • More complete answers can be obtained if there is doubt on both sides or a particular information is detected that is remarkable.
  • The researcher has an opportunity to detect and analyze the interviewee’s body language at the time of asking the questions and taking notes about it.


  • They are time-consuming and extremely expensive.
  • They can generate distrust on the part of the interviewee, since they may be self-conscious and not answer truthfully.
  • Contacting the interviewees can be a real headache, either scheduling an appointment in workplaces or going from house to house and not finding anyone.
  • Therefore, many interviews are conducted in public places, such as shopping centers or parks. There are even consumer studies that take advantage of these sites to conduct interviews or surveys and give incentives, gifts, coupons, in short; There are great opportunities for online research in shopping centers.
  • Among the advantages of conducting these types of interviews is that the respondents will have more fresh information if the interview is conducted in the context and with the appropriate stimuli, so that researchers can have data from their experience at the scene of the events, immediately and first hand. The interviewer can use an online survey through a mobile device that will undoubtedly facilitate the entire process.

Telephonic Interviews:

Telephonic interviews are widely used and easy to combine with online surveys to carry out research effectively.


  • To find the interviewees it is enough to have their telephone numbers on hand.
  • They are usually lower cost.
  • The information is collected quickly.
  • Having a personal contact can also clarify doubts, or give more details of the questions.


  • Many times researchers observe that people do not answer phone calls because it is an unknown number for the respondent, or simply already changed their place of residence and they cannot locate it, which causes a bias in the interview.
  • Researchers also face that they simply do not want to answer and resort to pretexts such as they are busy to answer, they are sick, they do not have the authority to answer the questions asked, they have no interest in answering or they are afraid of putting their security at risk.
  • One of the aspects that should be taken care of in these types of interviews is the kindness with which the interviewers address the respondents, in order to get them to cooperate more easily with their answers. Good communication is vital for the generation of better answers.

Email or Web Page Interviews:

Online research is growing more and more because consumers are migrating to a more virtual world and it is best for each researcher to adapt to this change.

The increase in people with Internet access has made it popular that interviews via email or web page stand out among the types of interviews most used today. For this nothing better than an online survey.

More and more consumers are turning to online shopping, which is why they are a great niche to be able to carry out an interview that will generate information for the correct decision making.

Advantages of email surveys:

  • Speed in obtaining data
  • The respondents respond according to their time, at the time they want and in the place they decide.
  • Online surveys can be mixed with other research methods or using some of the previous interview models. They are tools that can perfectly complement and pay for the project.
  • A researcher can use a variety of questions, logics, create graphs and reports immediately.

Undoubtedly, the objective of the research will set the pattern of what types of interviews are best for data collection. Based on the research design, a research can plan and test the questions, for instance, if the questions are the correct and if the survey flows in the best way.

In addition there are other types of research that can be used under specific circumstances, for example in the case of no connection or adverse situations to carry out surveyors, in these types of occasions it is necessary to conduct a field research, which can not be considered an interview if not rather a completely different methodology.

To summarize the discussion, an effective interview will be one that provides researchers with the necessary data to know the object of study and that this information is applicable to the decisions researchers make.

Learn more: Quantitative Research