Structured vs. unstructured interviews: A complete guide

When researching a specific subject, interviews can be extremely helpful. Researchers use semi-structured, unstructured, and structured interviews or focus groups to glean vital insights into a topic.

Interviews can help you understand the context of a subject, eyewitness accounts of an event, people's perceptions of a product, and more.

In some instances, semi-structured or unstructured interviews can be more helpful; in others, structured interviews are the right choice to obtain the information you seek.

In some cases, structured interviews can save time, making your research more efficient. Let’s dive into everything you need to know about structured interviews.

Structured interviews are also known as standardized interviews, patterned interviews, or planned interviews. They’re a research instrument that uses a standard sequence of questions to collect information about the research subject. 

Often, you’ll use structured interviews when you need data that’s easy to categorize and quantify for a statistical analysis of responses.

Structured interviews are incredibly effective at helping researchers identify patterns and trends in response data. They’re great at minimizing the time and resources necessary for data collection and analysis.

What types of questions suit structured interviews?

Often, researchers use structured interviews for quantitative research. In these cases, they usually employ close-ended questions. 

Close-ended questions have a fixed set of responses from which the interviewer can choose. Because of the limited response selection set, response data from close-ended questions is easy to aggregate and analyze.

Researchers often employ multiple-choice or dichotomous close-ended questions in interviews. 

For multiple-choice questions, interviewees may choose between three or more possible answers. The interviewer will often restrict the response to four or five possible options. An interviewee will likely need help recalling more, which can slow down and complicate the interview process. 

For dichotomous questions, the interviewee may choose between two possible options. Yes or no and true or false questions are examples of dichotomous questions.

Open-ended questions are common in structured interviews. However, researchers use them when conducting qualitative research and looking for in-depth information about the interviewee's perceptions or experiences. 

These questions take longer for the interviewee to answer, and the answers take longer for the researcher to analyze. There's also a higher possibility of the researcher collecting irrelevant data. However, open-ended questions are more effective than close-ended questions in gathering in-depth information.

Sometimes, researchers use structured interviews in qualitative research. In this case, the research instrument contains open-ended questions in the same sequence. This usage is less common because it can be hard to compare feedback, especially with large sample sizes.

Researchers conduct structured interviews face-to-face, via telephone or videoconference, or through a survey instrument. 

Face-to-face interviews help researchers collect data and gather more detailed information. They can collect and analyze facial expressions, body language, tone, and inflection easier than they might through other interview methods. 

However, face-to-face interviews are the most resource-intensive to arrange. You'll likely need to assume travel and other related logistical costs for a face-to-face interview. 

These interviews also take more time and are more vulnerable to bias than some other formats. For these reasons, face-to-face interviews are best with a small sample size.

You can conduct interviews via an audio or video call. They are less resource-intensive than face-to-face interviews and can use a larger sample size. 

However, it can be difficult for the interviewer to engage effectively with the interviewee within this format, which can inject bias or ambiguity into the responses. This is particularly true for audio calls, especially if the interviewer and interviewee have not met before the interview. 

A video call can help the interviewer capture some data from body language and facial expressions, but less so than in a face-to-face interview. Technical issues are another thing to consider. If you’re studying a group of people that live in an area with limited Internet connectivity, this can make a video call challenging.

Survey questionnaires mirror the essential elements of structured interviews by containing a consistent sequence of standard questions. Surveys in quantitative research usually include close-ended questions. This data collection method can be beneficial if you need feedback from a large sample size.

Surveys are resource-efficient from a data administration standpoint but are more limited in the data they can gather. Further, if a survey question is ambiguous, you can’t clear up the ambiguity before someone responds. 

By contrast, in a face-to-face or tele-interview, an interviewee may ask clarifying questions or exhibit confusion when asked an unclear question, allowing the interviewer to clarify.

Structured interviews are relevant in many fields. You can find structured interviews in human resources, marketing, political science, psychology, and more. 

Academic and applied researchers commonly use them to verify insights from analyzing academic literature or responses from other interview types.

However, one of the most common structured interview applications lies outside the research realm: Human resource professionals and hiring managers commonly use these interviews to hire employees.

A hiring manager can easily compare responses and whittle down the applicant pool by posing a standard set of closed-ended interview questions to multiple applicants. 

Further, standard close-ended or open-ended questions can reduce bias and add objectivity and credibility to the hiring process.

Structured interviews are common in political polling. Candidates and political parties may conduct structured interviews with relatively small voter groups to obtain feedback. They ask questions about issues, messaging, and voting intentions to craft policies and campaigns.

The tools you need to conduct a structured interview vary by format. But fundamentally, you will need: 

• A participant

• An interviewer

• A pen and pad (or other note-taking tools)

• A recording device

• A consent form

• A list of interview questions

While some interviewees may express qualms about you recording the interview, it’s challenging to conduct quality interviews while taking detailed notes. Even if you have a note-taker in the room, note-taking may introduce bias and can’t capture body language or facial expressions. 

Depending on the nature of your study, others may wish to review your sources. If they call your conclusions into question, audio recordings are additional evidence in your favor.

To record, you should ask the interviewee to sign a consent form. Check with your employer's legal counsel or institutional review board at your academic institution for guidance about obtaining consent legally in your state. 

If you're conducting a face-to-face interview, a camcorder, digital camera, or even some smartphones are sufficient for recording.

For a tele-interview, you'll find that today's leading video conferencing software applications feature a convenient recording function for data collection.

If a survey is your method of choice, you'll need the survey and a distribution and collection method. Online survey software applications allow you to create surveys by inputting the questions and distributing your survey via text or email. 

In some cases, survey companies even offer packages in which they will call those who do not respond via email or text and conduct the survey over the phone.

If you're planning a face-to-face interview, you'll need to take a few steps to do it efficiently. 

First, prepare your questions and double-check that the structured interview format is best for your study. Make sure that they are neutral, unbiased, and close-ended. Ask a friend or colleague to test your questions pre-interview to ensure they are clear and straightforward.

Choose the setting for your interviews. Ideally, you'll select a location that is easy to get to. If you live in a city, consider addresses accessible via public transportation. 

The room where your interview takes place should be comfortable, without distraction, and quiet, so your recording device clearly captures your interviewee's audio.

If you're looking to interview people with specific characteristics, you'll need to recruit them. Some companies specialize in interview recruitment. You provide the attributes you need, and they identify a pool of candidates for a fee. Alternatively, you can advertise to participants on social media and other relevant avenues. 

If you're looking for college students in a specific region, look at student newspaper ads or affiliated social media pages. 

You'll also want to incentivize participation, as recruiting interview respondents without compensation is exceedingly difficult. It’s best to include a line or two about requiring written consent for participation and how you’ll use the interview audio.

When you have an interview participant, discuss the intent of your research and acquire their consent. Ensure your recording tools are working well, and begin your interview. 

Don't rely on the recordings alone: Note the most significant insights from your participant, as you could easily forget them when it's time to analyze your data.

You'll want to transcribe your audio at the data analysis stage. Some recording applications use AI to generate transcripts. Remove filler words and other sounds to generate a clear transcript for the best results. 

A written transcript will help you analyze data and pull quotes from your audio to include in your final research paper.

Typically, you'll find researchers using at least one of these other common interview types:

Semi-structured interviews

As the name suggests, semi-structured interviews include some elements of a structured interview. You’ll include preplanned questions, but you can deviate from those questions to explore the interviewee's answers in greater depth.

Typically, a researcher will conduct a semi-structured interview with preplanned questions and an interview guide. The guide will include topics and potential questions to ask. Sometimes, the guide may also include areas or questions to avoid asking.

Unstructured interviews

In an unstructured interview, the researchers approach the interview subjects without predetermined questions. Researchers often use this qualitative instrument to probe into personal experiences and testimony, typically toward the beginning of a research study. 

Often, you’ll validate the insights you gather during unstructured and semi-structured interviews with structured interviews, surveys, and similar quantitative research tools.

Focus group interviews

Focus group interviews differ from the other three types of interviews as you pose the questions to a small group. Focus groups are typically either structured or semi-structured. When researchers employ structured interview questions, they are typically confident in the areas they wish to explore. 

Semi-structured interviews are perfect for a researcher seeking to explore broad issues. However, you must be careful that unplanned questions are unambiguous and neutral. Otherwise, you could wind up with biased results.

A structured interview consists of standard preplanned questions for data collection. These questions may be close-ended, open-ended, or a combination. 

By contrast, an unstructured interview includes unplanned questions. In these interviews, you’ll usually equip facilitators with an interview guide. This includes guidelines for asking questions and samples that can help them ask relevant questions.

Relative to other interview formats, a structured interview is usually more time-efficient. With a preplanned set of questions, your interview is less likely to go into tangents, especially if you use close-ended questions. 

The more structure you provide to the interview, the more likely you are to generate responses that are easy to analyze. By contrast, an unstructured interview may involve a freewheeling conversation with off-topic and irrelevant feedback that lasts a long time.

A structured question is any question you ask in an interview that you’ve preplanned and standardized.

For example, if you conduct five interviews and the first question you ask each one is, "Do you believe the world is round, yes or no?" you have asked them a structured question. This is also a close-ended dichotomous question.