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Survey and questionnaire studies

A survey study gathers standardized responses from a defined population using a sampling and measurement plan suited to its research question.
NHMRC EVIDENCE LEVEL · 2009Not yet classifiedProvisional design classification. Study quality and certainty of findings require separate appraisal.
Why this level?Specify the research question: intervention, diagnostic accuracy, prognosis, aetiology, or screening intervention. Other question types are outside this hierarchy. NHMRC 2009 source

A survey is a way to gather responses, not a fixed causal design. The sampling frame and response process determine who the findings describe; repeated surveys and surveys embedded in trials have additional design requirements.

What question does this help answer?

What do people report about their symptoms, experiences, knowledge or practices, and how do those reports vary? A questionnaire is the measurement instrument; the study also needs a defensible plan for whom to invite and what responses can represent.

When to use it

Use a survey when the needed information can reasonably be reported by participants and a suitable recruitment route exists. Distinguish a one-time snapshot, repeated samples and follow-up of the same respondents, since their analyses and limitations differ.

When not to use it

Do not rely on self-report when the question requires measurements respondents cannot supply reliably. An open web link can describe its respondents but does not automatically estimate prevalence in the wider patient or clinician population. A cross-sectional association also needs care about temporal ordering.

Start by choosing the instrument

Search for a suitable existing instrument before writing new items. Check evidence for the intended construct, population, language and use, plus permissions and scoring rules. Reliability describes consistency; it does not establish that the score measures the construct you need. A translated or shortened instrument needs evidence for that version.

If questions need to be developed or adapted

Map items to the construct, involve relevant participants and experts, and use cognitive interviewing to examine how respondents understand the questions. Pilot wording, response options, branching and burden before launching. A few favorable pilot comments are not a complete validation study.

Key assumptions and design requirements

  • Define the target population and sampling frame, and describe whom the recruitment approach misses.
  • Prespecify the invitation and follow-up process, response denominators and handling of duplicate or ineligible submissions.
  • Use the instrument's scoring rules and distinguish unanswered items from a whole missing questionnaire.
  • State assumptions about nonresponse and item missingness; consider imputation or weighting only when their supporting information and assumptions are defensible.
  • Account for sampling weights and clusters when applicable, and for repeated responses from the same people in longitudinal surveys.

From target population to respondents

From target population to respondents. The sampling frame misses part of the target population, the drawn sample differs from the frame by chance, and nonresponse removes more people, so the respondents can differ from the population the question is about at every step.From the population in the question to the people who answeredTarget populationSampling frameNot in the frame: coverage errorSample drawnDiffers by chance: sampling errorRespondentsDid not respond: nonresponseA large number of responses does not repair a poor frame or selective participation: a precise estimateabout the wrong people is still wrong.
Conceptual diagram. It shows the structure of the idea, not data from any study.

Clinical example

A hospital wants to understand discharge instructions across language groups. It first checks an appropriate experience instrument and its translated versions, then samples eligible discharges and offers accessible response modes. It reports invited and responding patients by relevant characteristics, checks missing items and considers how people unreachable after discharge might differ. A satisfaction score among respondents is not automatically a hospital-wide estimate.

What to watch out for

A large number of responses does not repair a poor sampling frame, selective participation or an unsuitable questionnaire. Reliability alone does not establish validity, and weighting cannot guarantee that respondents represent nonrespondents.

How to report it

CROSS is the guideline for survey studies, and CHERRIES covers surveys administered over the internet. They ask how respondents were sampled and recruited, how the response rate was defined or calculated, whether the questionnaire was pretested, and how non-response was addressed. A reporting guideline is not a design manual: use it to make the study transparent, not as a substitute for careful design. Check the target journal's own requirements as well, which this page cannot know.

Before using this in your workspace

Record the population, instrument and version, scoring, sampling frame, recruitment dates and missing-data plan beside the aim. If the purpose is to develop a new scale, make measurement validation an explicit objective with its own design.

Recent studies that used this
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Sources & further reading
  1. A Consensus-Based Checklist for Reporting of Survey Studies (CROSS) (opens in a new tab) · J Gen Intern Med · doi 10.1007/s11606-021-06737-1
  2. Developing questionnaires for educational research: AMEE Guide No. 87 (opens in a new tab) · Med Teach · doi 10.3109/0142159X.2014.889814
  3. Translation and Cross-Cultural Adaptation: A Critical Step in Multi-National Survey Studies (opens in a new tab) · J Korean Med Sci · doi 10.3346/jkms.2024.39.e336
  4. Improving the quality of Web surveys: the Checklist for Reporting Results of Internet E-Surveys (CHERRIES) (opens in a new tab) · J Med Internet Res · doi 10.2196/jmir.6.3.e34
Prepared with AI assistance; source records rechecked 2026-09-09. Publication follows agent methodological review under the owner’s expansion request; no independent professional approval is claimed. CROSS supports reporting. The questionnaire guide focuses on educational research; instrument selection and validation must be justified for the clinical construct and intended respondents.
Last source review: 2026-09-08
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Mallard uses reputable methodological and reporting sources, but this material may contain errors or omit important context. Verify important methodological decisions with the cited sources and, when appropriate, a qualified research methodologist or statistician.