What Are IDIs? Explaining In-depth Interviews in Market Research

Wish you could have a detailed conversation with key customers or target prospects to gather feedback about your brand, products, or services?

In-depth interviews (IDIs) are an excellent type of market research to accomplish this goal.

Keep reading to learn more about IDIs including the definition and the process you can expect when partnering with a third-party market research company.

Defining and explaining in-depth interviews (IDIs)

Choosing a Methodology: Explore or Measure?

As a market research company serving organizations from coast to coast, we know all about IDIs and can walk you through everything you need to know about this market research methodology.

We also know choosing a research methodology can be tough if you are new to research or unsure about the benefits of different research methodologies.

The decision on what methodology to use in a market research study is often based on two factors:

  • What are your objectives?
  • What is your timeline?

First, it's important to understand the objectives of the study.

Market research companies such as Drive Research guide clients through the process of choosing qualitative or quantitative methodologies and discuss the benefits of each.

Quantitative research methodologies are best for measuring while qualitative is best for exploring. 

Second, it's important to understand the timeline or when the results from the study are needed by.

Typically, it's safe to say an online survey project can be completed faster than phone surveys.

For more context, learn more about how long different market research methodologies take.

What are In-Depth Interviews (IDIs)?

Before diving into the process, let's quickly discuss a quick definition of in-depth interviews or IDIs for short.

What is the definition of IDIs?
An IDI is a conversation led by a market research interviewer with another individual. Typically, these conversations last between 20 to 30 minutes and are done over the phone or in person. IDIs are great for exploring new concepts like products/services, the reasoning behind decision-making, and more.

Common FAQs About IDIs

How long do IDIs take?

The length of a market research interview often depends on the objectives of the research.

For example, if an organization wanted to get insight on customers' user experience (UX) on its website, the IDIs may be completed through online screen-sharing software and could take upwards of 45 minutes.

However, a conversation about an organization merger and a re-brand could take anywhere from 20 to 30 minutes.

The budget available can also play a role in the length of an in-depth interview. For example, a 90-minute interview will likely require a higher incentive for people to participate. It could also take longer to find people who can find the time to join that lengthy of a discussion.

All of these types of factors play a role in higher market research costs.

How many IDIs are needed?

Of course, it always depends on the objectives of the study, but market research companies usually recommend anywhere from 8 to 14 interviews depending on how difficult the audience is to reach.

After roughly 8 interviews, our team often hears repeat information and common themes in the interviews.

IDIs vs. phone surveys: What's the difference?

Here is a question we hear a lot. The guide for an IDI is looser and interviewers are trained to dig deeper throughout the conversation. It is a two-way communication where an interviewer can probe more detailed responses.

Phone surveys, however, only take a few minutes to complete, ask mainly close-ended questions, and limit follow-up questions.

Additionally, phone surveys are much more rigid than IDIs which don't allow too much wiggle room to ask follow-up questions throughout the entire survey.

Conducting IDIs with a Third-Party Research Firm

Oftentimes this research methodology uses a third-party research company to lead a conversation.

Here's an inside look at the IDI process.

Step #1: Kickoff Meeting

It all starts with the kickoff meeting. Here is where market research pros will walk clients through the finer details of the project. This includes reviewing the objectives, timeline, interview criteria, honorariums, and more.

Learn more about market research kickoff meetings and what should be covered.

Step #2: Recruiting

The recruiting process is when the market research team will start seeking interview candidates. Depending on how specific the interview criteria are, this process could last a week or less, or several weeks.

Safe to say recruiting general consumers within a target market is faster than CEOs that work for Fortune 500 companies.

Learn more about our detailed qualitative recruiting process.

Step #3: Fieldwork

The fieldwork stage is when the actual interviews take place. Qualified market research interviewers like to think of themselves as gold miners who try to find pieces of information to help clients drive future strategy.

Learn more about what makes a great research interviewer.

Step #4: Reporting

In this step, the market research team takes the findings from all of the interviews and presents them in an IDI market research report. Audio files can also be included in the report package so clients are able to go back and listen to interviews if needed.

Step #5: Debrief 

After the report has been delivered, the market research team will review the findings. The discussion will cover the background and methodology of the study briefly and then focus on the key findings from the research.

Contact Drive Research to Conduct IDIs

Drive Research is a full-service market research company specializing in in-depth interviews. We work with brands from across the country to execute IDIs whether it be in person, via phone, or through video conferencing.

Our market research firm offers related services to offer end-to-project management such as finding and scheduling participants, interview design guide, interviewing, reporting, and more.

To learn more about our services or contact our team for a quote, reach out through one of the four ways below.

  1. Message us on our website
  2. Email us at [email protected]
  3. Call us at 888-725-DATA
  4. Text us at 315-303-2040

emily taylor about the author

Emily Taylor

As a Senior Research Analyst, Emily is approaching a decade of experience in the market research industry and loves to challenge the status quo. She is a certified VoC professional with a passion for storytelling.

Learn more about Emily, here.

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