12 Common Qualitative Interview Mistakes That Weaken Research Findings

Qualitative interview mistakes quietly weaken dissertation findings, and nobody notices them until the transcripts are coded. In 12 years of guiding students, I have read a great many interview transcripts, and the pattern repeats: a student completes 12 interviews, gets thin answers, and then cannot build themes worth defending. The participants are rarely the problem, because how the questions were asked usually is.

Below are the 12 qualitative interview mistakes I see most often, each with a weak and an improved question. At the end, there is a 10-minute transcript audit that you can run on your own data.

Common Mistakes in Qualitative Interviews at a Glance

Qualitative interview mistakes are errors in question wording, probing, listening, or preparation that push participants towards shallow, biased, or inconsistent answers, so the themes you build from their transcripts become harder to defend in front of a supervisor or examiner.

Here are the 12 common qualitative interview mistakes, in the order I explain them:

1. Asking leading questions
2. Asking multiple questions together
3. Failing to probe
4. Over-relying on scripted questions
5. Asking closed questions that collect superficial responses
6. Talking too much and rushing silences
7. Using jargon or abstract wording
8. Skipping the pilot interview
9. Rushing rapport
10. Showing approval or reacting to answers
11. Keeping a guide disconnected from your research questions
12. Poor recording and no reflection after the interview

Two terms you will meet in your methodology chapter: a semi-structured interview uses a prepared guide but allows flexible follow-up questions, and thick description means detailed, context-rich accounts that show what happened, how it felt, and why.

Why Qualitative Interview Mistakes Matter More Than You Think

In a survey the question is fixed, so it cannot lead anyone, but in an interview you are the instrument and your habits become part of the data. That is why qualitative interview mistakes weaken credibility, one of the four trustworthiness criteria described by Lincoln and Guba (1985), alongside transferability, dependability and confirmability.

How Interview Quality Shapes Your Themes

Thematic analysis, as set out by Braun and Clarke (2006), can only work with what exists in the transcript. Thin answers produce descriptive themes such as “workload” or “stress”, while leading questions produce themes that quietly repeat your own assumptions. In both cases, qualitative interview mistakes made in week two show up as weak findings in month six.

What Supervisors and Examiners Notice

Some examiners read appendix transcripts early, and in vivas a common question is, “How did you make sure your questions did not lead participants?” A pilot, a reflexive journal and clean transcripts let you answer that question calmly, whereas without them your answer sounds like guesswork.

Mistakes 1 to 4: Leading Questions in Qualitative Research and How You Ask

Mistake 1: Asking Leading Questions

A leading question in qualitative research contains an assumption, or hints at the expected answer, so the participant responds to your view instead of describing their own experience. A single word such as “improve” or “stressful” can be enough to do this.

Effect on findings: Participants agree to be polite, and your theme then reflects your own opinion, which your audit trail and your examiner will both be able to see.

Mistake 2: Asking Multiple Questions Together

A double-barrelled question asks about two or more things in one sentence, so the participant cannot tell which part to answer and you cannot tell which part they actually answered. It is one of the quickest qualitative interview mistakes to fix once you can recognise it.

Effect on findings: Participants answer the last or easiest part, so your coding has gaps that you cannot explain later.

Mistake 3: Failing to Probe

Failing to probe is one of the qualitative interview mistakes that costs students the most marks, because a participant says something important in one line and the researcher moves on. Look at the difference:

Effect on findings: Without probes you collect labels instead of thick description, and your themes stay at surface level. I explain exact techniques in the probing section below.

Mistake 4: Over-Relying on Scripted Questions

A semi-structured guide is a map, not a script. If a participant mentions her manager in passing and you still read question 7, you miss the lead; follow it for two or three minutes, then return to the guide.

Effect on findings: Rigid interviews miss unexpected insights, which is usually the reason you chose a qualitative design in the first place, and small follow-ups within approved topics are normally fine, but see the ethics answer in the FAQ.

Qualitative Interview Probing Techniques That Actually Work

Good probing fixes several qualitative interview mistakes at once, so it deserves its own section before we continue with the rest of the list.

What Is Probing in a Qualitative Interview?

Probing means asking short, neutral follow-up questions that invite a participant to clarify, expand, or illustrate what they have just said, without adding any idea of your own. A good probe asks for more of the participant’s experience, never for agreement with your assumption.

These qualitative interview probing techniques work in almost every discipline:

• Clarify: “What do you mean by stressful?”
• Elaborate: “Can you tell me more about that?”
• Ask for an example: “Can you recall one specific time?”
• Contrast: “How was that different from your previous job?”
• Reflect back: “So the handover felt rushed. Did I understand that right?”
• Use silence: Wait three to five seconds after an answer, because people often add the real point after a pause.

How Many Probes Are Too Many?

There is no official number, but my own rule of thumb is two or three follow-ups per main question, and fewer on sensitive topics. Stop when answers start repeating or when the participant looks uncomfortable with the topic.

What If a Participant Gives One-Word Answers?

Slow down and try these steps in order:

1. Switch from “why” to “tell me about a time when”.
2. Ask about one specific day or event.
3. Check if the question itself was closed (mistake 5).
4. Check your rapport (mistake 9).

Mistakes 5 to 8: Conversation Style and Preparation

Mistake 5: Closed Questions That Collect Superficial Responses

Effect on findings: Closed questions are among the most common qualitative interview mistakes in first-time dissertations, because a “yes” gives you nothing to code and your findings chapter becomes a list of one-liners. Thin interviews also make it hard to judge when you have enough data, so read about determining how many qualitative interviews are needed.

Mistake 6: Talking Too Much and Rushing Silences

Effect on findings: Your voice fills the transcript and the participant’s voice shrinks, and my rough benchmark, which is not a published rule, is to check your habits if your lines take up more than a quarter of the words.

Mistake 7: Using Jargon or Abstract Wording

Effect on findings: Participants guess what you mean and hand your own vocabulary back to you, which is not the data you went out to collect.

Mistake 8: Skipping the Pilot Interview

Skipping a pilot is one of the easiest qualitative interview mistakes to avoid. Run one or two pilots with people similar to your participants, ask which questions confused them, and rewrite those.

Effect on findings: Without a pilot, you discover that a question is confusing only after you have used up some of your scarce participants.

Mistakes 9 to 12: Rapport, Bias and Follow-Through

Mistake 9: Rushing Rapport

Effect on findings: Without rapport, participants give safe, polished answers. This is called social desirability bias, which means people answer in ways they think look acceptable.

Mistake 10: Showing Approval or Reacting to Answers

Effect on findings: Participants adjust their answers to please you, which is called the interviewer effect. This is one of the qualitative interview mistakes you cannot easily see in yourself, so use reflexivity, which means openly examining how your background, beliefs and reactions may shape the data you collect and how you read it.

Mistake 11: Keeping a Guide Disconnected from Your Research Questions

Write each interview question next to the research question it serves, and remove any question with no match. Also check that interviews suit your aim in the first place, because “how many” questions belong to a survey. See choosing an appropriate research design and identifying a clearly defined research gap.

Effect on findings: A disconnected guide is one of the qualitative interview mistakes that only shows at analysis stage, when you hold interesting transcripts that cannot answer your research questions.

Mistake 12: Poor Recording and No Reflection After the Interview

Effect on findings: Lost audio and lost context cannot be recovered at the analysis stage, however carefully you code. If you are planning original interviews, read about collecting primary research data first.

Qualitative Interview Questions Examples: Weak vs Improved

These pairs fix the qualitative interview mistakes covered above, so use them as templates for your own guide.

A Simple Rule for Rewriting Any Weak Question

1. Remove the assumption (words like “improve”, “stressful”, “poor”).
2. Keep one idea per question.
3. Ask for a story or example, not a yes or no.

How Qualitative Interview Mistakes Affect Coding and Credibility

This table shows where each of the qualitative interview mistakes hurts you at the analysis stage.

Two Short Case Studies from My Practice

Both cases below show qualitative interview mistakes that repeat across disciplines. They are composites, with details changed to protect privacy.

Case 1: UK MSc nursing student. She interviewed 10 nurses about night shifts and asked, “How tiring was night shift for you?” in almost every interview, and all 10 transcripts produced a “fatigue” theme. Her supervisor asked whether any nurse raised fatigue without being prompted, and none had. She wrote a limitation and re-interviewed four nurses with neutral questions.

Case 2: US MBA student. He interviewed eight managers about hybrid working and asked mostly yes or no questions, so most answers ran to two or three lines. After we added probes such as “Can you give me an example?”, three re-interviews produced a new theme: invisible workload.

What Popular Guides Say About Qualitative Interview Mistakes, and Where I Disagree

I read the common guides before writing this, and here is my honest opinion on each.

• Grad Coach. It lists five costly mistakes and begins with a clear interview strategy, with questions linked to your research aims. I agree with that “golden thread”, but five mistakes is too few, and drifting between interviews is not always a flaw when a deliberately unstructured design is justified in the methodology.
• dscout (People Nerds). The author listens to every full session afterwards and scores herself with a template, a habit that mistake 12 borrows. My critique is that it is written for UX researchers and that self-scoring has a blind spot, because you grade yourself with the same bias that caused the error, so ask your supervisor to listen to one pilot.
• The Farnsworth Group. It suggests warm-up questions and a neutral third-party interviewer. The warm-up advice is sound, but a third-party interviewer is a market research luxury that students rarely have, so your substitute is reflexivity and supervisor review.
• The Qualitative Report (2015). A novice researcher analysed her own first interviews and found that she lost track, steered participants, and lacked clarity, so her voice drowned out theirs. I admire the honesty and it matches my experience, but it is one researcher using unstructured interviews, so treat it as a warning and not as proof.
• Listen Labs. It lists weak probing among its 12 mistakes and promotes AI-moderated interviews at scale. Scale solves sample size and not question quality, because five hundred leading questions still give biased data, and the source is a vendor with a product to sell.

For deeper reading, I suggest Kvale and Brinkmann’s InterViews (3rd ed., 2015) alongside the Braun and Clarke paper linked above.

How to Improve Qualitative Interview Quality: A 7-Step Checklist

Use this checklist to prevent qualitative interview mistakes before they enter your data.

1. Link every question to a research question. Delete any question without a link.
2. Decide how many interviews you need. Plan how you will recognise that you have enough data, and justify it in your methodology.
3. Recruit with care. Taking only easy-to-reach friends affects credibility, so read about the limitations of convenience sampling.
4. Write open, single, plain questions. Add two or three probes under each one.
5. Pilot twice, then rewrite.
6. Interview with a calm, neutral stance. Let silence work.
7. Listen back after every interview. Note your talk time and write a short reflexive memo.

The 10-Minute Transcript Audit

Run this audit on one transcript to spot qualitative interview mistakes quickly. Use the table below as your on-page transcript audit sheet.

Online Interview Tips (Zoom and Teams)

Online interviews add their own qualitative interview mistakes, and two common ones are interrupting a pause that was only a weak connection and trusting auto-transcripts without checking them. Test audio beforehand, keep sessions shorter, confirm recording consent on the call, and correct every transcript against the audio.

Already Collected Your Data? How to Salvage It

If you find qualitative interview mistakes after data collection, do not panic. Follow these three steps:

1. Mark every leading or double-barrelled question in your transcripts.
2. Count the thin answers.
3. Decide whether to re-interview a few participants or to report the issue as a limitation.

How to Write It in Your Methodology and Limitations

Describe the qualitative interview mistakes you found, what you did about them, and how you interpreted the affected extracts, for example: “Review of the first three transcripts showed that some questions assumed fatigue, so I flagged the affected extracts, conducted four follow-up interviews using neutral wording, and interpreted the original extracts with caution.” Pair this with your reflexive journal, and see documenting research procedures in your methodology chapter.

When Is It Worth Re-Interviewing?

Re-interview when the mistakes touch your main research question, or when most of your transcripts are thin. If the problem is minor and affects only a few extracts, disclosure is usually enough, and your supervisor can help you decide.

Next Steps: From Interviews to Thematic Analysis

Cleaner transcripts also make analysis faster, because fewer qualitative interview mistakes means fewer ambiguous extracts to explain. Transcribe verbatim, check automated text against the audio, and then begin coding with the Braun and Clarke phases. Prepare a reflexivity statement too, for example: “As a former nurse, I recognise that my own night-shift experience may have shaped my probing, so I kept a journal after each interview to record my reactions.”

Get Expert Eyes on Your Interview Guide

A second reader often spots qualitative interview mistakes that you cannot see in your own guide, and that is completely normal. Statssy’s dissertation expert support can review your interview guide, transcripts and methodology wording before your supervisor does. You can start with the signs you need a dissertation expert or how to find a dissertation writing mentor.

Frequently Asked Questions

What are the most common qualitative interview mistakes?

The most frequent qualitative interview mistakes are leading questions, asking several questions at once, failing to probe, and following the script too rigidly. Talking too much and skipping a pilot come next, and each one reduces the depth and credibility of your findings.

What are probing questions in a qualitative interview?

Probing questions are short, neutral follow-ups such as “Can you give me an example?” or “What do you mean by that?” They turn one-line replies into material you can code.

How do I avoid bias in a qualitative interview?

Use neutral wording, avoid reacting with approval, and keep a reflexive journal. Pilot your guide and ask your supervisor to review one recording, because you cannot remove bias fully but you can show how you managed it.

How long should a qualitative interview last?

Many dissertation interviews run 30 to 60 minutes, and some topics need longer. Depth matters more than length, so plan time for rapport, main questions and probes.

What is the difference between structured, semi-structured and unstructured interviews?

Structured interviews use the same fixed questions in the same order, and semi-structured interviews use a guide but allow follow-up questions. Unstructured interviews have only a broad topic and follow the participant’s lead, and most qualitative dissertations choose semi-structured.

What are the key principles of a good qualitative interview?

There is no single official list, but here is the six-point list I use: a clear purpose, open questions, a neutral stance, active listening, probing, and careful recording.

Can I change my interview questions after ethics approval?

Small wording changes and extra probes within approved topics are usually acceptable, but new topics, sensitive questions or changes to consent normally need an amendment. The British Sociological Association’s ethics guidance is a useful starting point in the UK, and in the US your IRB follows rules overseen by the Office for Human Research Protections. Psychology students can also check the British Psychological Society or American Psychological Association codes, and you should always ask your own ethics committee first.

Can I still use my data if I made these mistakes?

Often yes. Audit your transcripts, mark the weak questions, decide whether to re-interview a few participants, and describe the issue openly in your methodology or limitations section.

Can pilot interviews be included in my sample?

Usually not, because the guide changes after a pilot. If your guide stays the same and your supervisor agrees, some researchers include them, but you must say so clearly.

How many interviews do I need?

It depends on your design, your topic, and when new interviews stop adding new ideas, which is called saturation. Plan this early, justify it in your methodology, and see my guide to how many qualitative interviews are enough.

Final Thoughts

Most qualitative interview mistakes are habits and not talent problems, and habits can be fixed. Rewrite your guide, pilot it, probe more, and talk less, and your findings chapter will show the difference.

About the author: Siddharth Gupta is an independent analyst with 12 years of experience guiding dissertation and research students.

References

• Braun, V. and Clarke, V. (2006) ‘Using thematic analysis in psychology’, Qualitative Research in Psychology, 3(2), pp. 77-101.
• Gesch-Karamanlidis, E. (2015) ‘Reflecting on novice qualitative interviewer mistakes’, The Qualitative Report, 20(5), pp. 712-726.
• Kvale, S. and Brinkmann, S. (2015) InterViews: Learning the Craft of Qualitative Research Interviewing. 3rd edn. Thousand Oaks, CA: SAGE.
• Lincoln, Y.S. and Guba, E.G. (1985) Naturalistic Inquiry. Newbury Park, CA: SAGE.