The primary difference between a survey and a structured interview lies in their data gathering methods, particularly concerning the type of data collected and the nature of the questions asked.
Surveys and structured interviews are both common methods used in research, market analysis, and social science to collect information from individuals. While they both involve asking questions, they differ significantly in their approach, flexibility, and the type of data they typically yield.
Core Distinction: Quantitative vs. Qualitative and Question Types
Based on expert analysis, the fundamental difference is:
The difference between a survey and a structured interview is that a survey is a quantitative method of gathering data and usually involves closed-ended questions. Meanwhile, a structured interview is a qualitative method of gathering data and usually involves open-ended questions.
This distinction is crucial for researchers deciding which method is most appropriate for their study objectives.
- Quantitative data focuses on numerical measurements and statistical analysis, allowing for broad comparisons and identification of trends across a large sample.
- Qualitative data focuses on in-depth understanding of experiences, opinions, and perspectives, providing rich, detailed insights that can explain why certain patterns exist.
Comparing Surveys and Structured Interviews
Here's a breakdown of the key differences:
| Feature | Survey | Structured Interview |
|---|---|---|
| Primary Data Type | Quantitative | Qualitative |
| Typical Question Type | Primarily Closed-ended Questions | Primarily Open-ended Questions |
| Administration | Self-administered (online, paper) or researcher-administered (phone, in-person) | Typically researcher-administered (in-person, phone, video call) |
| Flexibility | Low (standardized questions and order) | Moderate (standardized questions, but flexibility in probing) |
| Sample Size | Can handle very large samples | Typically involves smaller samples |
| Depth of Information | Limited (focuses on breadth) | High (focuses on depth) |
| Cost per Response | Generally lower | Generally higher |
| Time per Response | Shorter | Longer |
| Data Analysis | Statistical analysis of numerical data | Thematic analysis of text/audio data |
Detailed Look at Each Method
Surveys
Surveys are a highly efficient way to collect data from a large number of people. They typically use a predetermined set of questions presented in a standardized format.
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Characteristics:
- Often distributed widely (online, mail, phone, in-person).
- Relies heavily on closed-ended questions (e.g., multiple-choice, rating scales, yes/no).
- Ideal for measuring opinions, attitudes, behaviors, and characteristics across a population.
- Results are often presented statistically (percentages, averages, correlations).
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Examples:
- Customer satisfaction questionnaire with rating scales.
- Political poll asking for voting intentions.
- Demographic survey collecting age, income, and education.
Structured Interviews
Structured interviews follow a strict script of questions that are asked in a specific order to every participant. While the questions are standardized, the interaction allows for more in-depth responses than typically found in surveys.
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Characteristics:
- Conducted face-to-face, over the phone, or via video call.
- Uses a set of standardized, pre-written questions.
- Often includes open-ended questions that encourage participants to elaborate on their answers.
- The interviewer records responses, sometimes verbatim.
- While structured, the interviewer can sometimes use pre-approved probes to ask for clarification or more detail within the scope of the question.
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Examples:
- A job interview using a standard set of behavioral questions.
- A clinical assessment using a fixed questionnaire about symptoms.
- A market research interview asking consumers about their experiences with a product, following a script.
Choosing the Right Method
The choice between a survey and a structured interview depends on the research goals:
- Use a survey when you need to collect data from a large sample, quantify attitudes or behaviors, identify patterns across a population, and need results quickly and cost-effectively.
- Use a structured interview when you need detailed insights into individual experiences, understand the why behind responses, require high response rates (especially in specific populations), and can invest more time per participant.
In practice, researchers sometimes use a mixed-methods approach, perhaps starting with a survey to identify trends and then conducting structured interviews with a subset of participants to explore specific issues in greater depth.
