Structured and unstructured interviews are two different approaches used in employee selection. The main difference is the degree to which the questions, topics, evaluation criteria, and interview procedures are predetermined and consistently applied to candidates.
A structured interview uses a planned set of questions and evaluation criteria, allowing candidates to be assessed more consistently. An unstructured interview gives the interviewer greater flexibility to determine the questions and direction of the conversation during the interview.
The effectiveness of each approach is therefore closely related to how consistently candidates are assessed, how relevant the questions are to job performance, and how much subjective judgment influences the final decision.
What Is a Structured Interview?
A structured interview is an interview in which the interviewer follows a predetermined format. Candidates are generally asked the same or substantially similar questions, and their responses are evaluated using predefined criteria.
The standardized format makes it easier to compare candidates because each candidate is assessed against a relatively consistent set of questions and requirements.
Structured interviews can also incorporate scoring systems, behavioral questions, situational questions, or other job-related assessment techniques.
What Is an Unstructured Interview?
An unstructured interview does not follow the same level of standardization as a structured interview.
The interviewer may decide which questions to ask based on the candidate's previous answers, background, impressions, or the direction of the conversation.
This flexibility can make the conversation feel more natural, but it can also make comparisons between candidates more difficult because different candidates may receive different questions and evaluation criteria.
Structured vs. Unstructured Interviews
| Aspect | Structured Interview | Unstructured Interview |
|---|---|---|
| Questions | Predetermined or standardized | Flexible and developed during the interview |
| Evaluation | Based on predefined criteria | More dependent on interviewer judgment |
| Candidate comparison | Generally easier | More difficult |
| Consistency | Higher level of standardization | Lower level of standardization |
| Flexibility | More limited | Greater |
| Risk of subjective judgment | Can be reduced through standardization | Generally greater |
| Usefulness for selection | Useful when consistent assessment is required | Can provide conversational flexibility but may reduce comparability |
Why Are Structured Interviews Often More Effective?
One of the major advantages of structured interviews is that candidates can be evaluated using a common framework.
When candidates receive comparable questions and are assessed using consistent criteria, organizations can make more systematic comparisons between candidates.
Structured interviews can therefore reduce some of the subjectivity associated with informal interviewing.
They can also improve the consistency of information collected from different candidates, particularly when interviewers receive appropriate training and use clearly defined scoring criteria.
Interview Validity and Selection Effectiveness
Interview validity concerns the extent to which interview information provides meaningful evidence about characteristics or capabilities that are relevant to job performance.
An interview should not simply produce an impression of whether an interviewer likes or dislikes a candidate. The assessment should provide evidence that is relevant to the requirements of the position.
Validity can therefore be improved when interview questions are clearly connected to job requirements and when candidates are evaluated using appropriate criteria.
Structured Interviews and Candidate Comparability
Candidate comparability is one of the strongest practical advantages of a structured interview.
Suppose five candidates are applying for the same position. If each candidate is asked completely different questions, it becomes difficult to determine whether differences in their answers reflect actual differences in capability or simply differences in the questions they received.
A structured approach can reduce this problem by asking candidates comparable questions and evaluating their responses against predefined standards.
Behavioral Interviews
A behavioral interview asks candidates to describe how they handled situations or demonstrated competencies in the past.
For example, a candidate may be asked to describe a situation in which they:
- solved a difficult problem;
- demonstrated leadership;
- handled conflict;
- worked under pressure;
- persuaded another person; or
- worked as part of a team.
The underlying idea is that evidence from previous behavior may provide useful information about how a candidate has demonstrated relevant competencies.
Situational Interviews
A situational interview asks candidates how they would respond to a hypothetical situation.
For example:
"What would you do if a member of your team repeatedly failed to meet an important deadline?"
The candidate's answer can provide information about their reasoning, judgment, problem-solving approach, and understanding of the role.
However, what a candidate says they would do in a hypothetical situation may not always be identical to what they would actually do in a real workplace situation.
Behavioral vs. Situational Interviews
| Feature | Behavioral Interview | Situational Interview |
|---|---|---|
| Focus | Past behavior | Hypothetical future behavior |
| Typical question | "Tell me about a time when..." | "What would you do if..." |
| Evidence | Actual previous experience | Proposed response to a situation |
| Purpose | Explore demonstrated behavior | Assess reasoning and potential responses |
Common Interview Bias
Interview bias occurs when irrelevant or subjective factors influence the evaluation of a candidate.
Bias can affect both structured and unstructured interviews, although greater standardization can help reduce some forms of subjective judgment.
1. Expectancy Effect
The expectancy effect occurs when an interviewer develops an expectation about a candidate before or during the interview and subsequently interprets information in a way that supports that expectation.
For example, positive information in an application may cause an interviewer to approach the interview with an unusually favorable expectation.
2. Primacy Effect
The primacy effect occurs when information received early in an interview has a disproportionately strong influence on the interviewer's overall judgment.
An interviewer may form an early impression and then interpret later information through the lens of that initial judgment.
3. Contrast Effect
The contrast effect occurs when the evaluation of one candidate is influenced by the performance of another candidate interviewed immediately before them.
A strong candidate may therefore make an average candidate appear weaker, while a weak candidate may make an average candidate appear stronger.
4. Similar-to-Me Effect
The similar-to-me effect occurs when an interviewer responds more positively to a candidate because they share similar backgrounds, interests, attitudes, or characteristics.
This can result in an evaluation that is based partly on personal similarity rather than job-related evidence.
5. Personal Liking Bias
Personal liking bias occurs when an interviewer develops a favorable or unfavorable impression based on personal preferences or non-job-related similarities.
For example, sharing the same hobbies or interests should not automatically result in a higher assessment of a candidate's professional suitability.
6. Physical Cue Bias
Physical characteristics or presentation can sometimes influence impressions even when they are not relevant to job performance.
Such judgments can reduce the objectivity of the interview process when they influence the assessment without a legitimate job-related basis.
7. Quota Effect
The quota effect may occur when interviewers are working toward a predetermined number of candidates to select.
If the expected number of successful candidates has already been reached, later candidates may be evaluated differently even when their performance is comparable.
Why Unstructured Interviews Can Be More Subjective
The flexibility of an unstructured interview can create opportunities for subjective judgment.
Because questions may differ from one candidate to another, the interviewer may unintentionally focus on different information when assessing each candidate.
The interviewer may also spend more time discussing topics that create a favorable impression while spending less time exploring evidence related to actual job requirements.
This makes systematic candidate comparison more difficult.
Can Structured Interviews Eliminate Interview Bias?
No. Structured interviews cannot completely eliminate interview bias.
However, standardization can reduce some sources of unnecessary subjectivity by giving candidates comparable questions and establishing consistent evaluation criteria.
Other safeguards can include interviewer training, multiple assessors, predefined scoring criteria, job-related questions, documentation of evidence, and periodic review of selection outcomes.
Structured Interviews and the Recruitment and Selection Process
Interviews are one component of the broader recruitment and selection process. They should therefore be considered alongside other selection methods and the specific requirements of the position.
An organization may use interviews together with application screening, work samples, skills assessments, references, tests, or other appropriate methods.
For a broader explanation of why organizations need an effective recruitment and selection process, see recruitment and selection process.
How to Improve the Effectiveness of Structured Interviews
1. Define Job Requirements
Interview questions should be based on the knowledge, skills, abilities, competencies, and other characteristics that are genuinely relevant to successful job performance.
2. Use Consistent Questions
Ask candidates comparable core questions so that their responses can be evaluated more systematically.
3. Establish Scoring Criteria
Define what constitutes a strong, moderate, or weak response before conducting interviews.
4. Train Interviewers
Interviewers should understand the purpose of each question, how to evaluate responses, and how to avoid irrelevant subjective judgments.
5. Record Evidence
Document relevant evidence from candidate responses rather than relying entirely on memory or general impressions.
6. Use Multiple Sources of Evidence
When appropriate, combine interview information with other job-related selection evidence.
7. Evaluate the Process
Organizations should periodically evaluate whether their interview process produces useful, consistent, and job-related hiring information.
Advantages of Structured Interviews
- greater consistency between candidates;
- easier comparison of responses;
- clearer evaluation criteria;
- reduced dependence on interviewer intuition;
- better documentation of selection decisions;
- greater alignment between questions and job requirements; and
- potentially improved reliability of candidate assessment.
Limitations of Structured Interviews
Structured interviews also have limitations.
- They may feel less conversational.
- Interviewers have less freedom to explore unexpected topics.
- Poorly designed questions can still produce poor assessments.
- Standardization does not automatically eliminate bias.
- Interview effectiveness depends on the quality of job analysis and evaluation criteria.
Advantages of Unstructured Interviews
Unstructured interviews can provide greater flexibility and allow interviewers to explore information that emerges naturally during the conversation.
They may be useful for exploratory conversations or situations where the interviewer needs flexibility to understand a candidate's background.
However, their flexibility should not be confused with higher selection validity. When candidates receive different questions and are assessed using inconsistent standards, candidate comparison can become more difficult.
Limitations of Unstructured Interviews
- greater interviewer subjectivity;
- inconsistent questions between candidates;
- difficulty comparing responses;
- greater opportunity for personal bias;
- difficulty recalling all candidate information; and
- potentially weaker connection between questions and job requirements.
Frequently Asked Questions
What is the difference between structured and unstructured interviews?
Structured interviews use predetermined questions and evaluation criteria, while unstructured interviews allow greater flexibility in the questions and direction of the conversation.
Which is more effective, structured or unstructured interviews?
Structured interviews are generally more suitable when organizations need consistent candidate comparison and job-related evaluation because they provide greater standardization.
What is interview validity?
Interview validity refers to the extent to which interview information provides meaningful evidence about characteristics or capabilities relevant to job performance.
What is a behavioral interview?
A behavioral interview asks candidates to describe actual past experiences and behaviors related to competencies required for the position.
What is a situational interview?
A situational interview asks candidates how they would respond to hypothetical situations related to the job.
What is interview bias?
Interview bias occurs when irrelevant personal impressions, expectations, similarities, or other subjective factors influence the evaluation of a candidate.
Can structured interviews eliminate bias?
No. Structured interviews can reduce some sources of subjectivity through standardization, but interviewer training, job-related criteria, documentation, and other safeguards are also important.
Why are structured interviews easier to compare?
Because candidates can receive comparable questions and be evaluated using predefined criteria, their responses can be assessed more systematically.
Conclusion
The effectiveness of structured and unstructured interviews depends largely on how the interview is designed, conducted, and evaluated.
Structured interviews generally provide greater consistency because candidates can be assessed using comparable questions and predefined criteria. Unstructured interviews provide greater conversational flexibility but can create greater difficulty when comparing candidates and controlling subjective judgment.
Behavioral and situational approaches can be incorporated into structured interviews when their questions are linked to relevant job requirements.
Organizations should also recognize common sources of interview bias, including expectancy effect, primacy effect, contrast effect, similar-to-me effect, physical cues, personal liking bias, and quota effects.
Ultimately, an effective interview should not be treated as an isolated activity. It should function as one evidence-based component of a broader recruitment and selection process designed to identify candidates whose capabilities are relevant to the requirements of the position.