Convenience sampling recruits people or selects cases because they are readily accessible. It is a non-probability approach: access does not give everyone in the population a known chance of selection. It can help with a small exploratory project, but a large convenient sample is not automatically representative.
A worked example: a campus library survey
Suppose you want to investigate students’ experience of quiet study space. You stand at the main library entrance between noon and 2pm and invite passing students to complete a questionnaire. This is a convenience sample because recruitment depends on who passes your location at those times and agrees to participate.
This is an invented planning example, not a completed study. Even if 200 students answer, the design can miss evening users, distance learners, people studying off campus and students who avoid the library because it is inaccessible. Those absences are relevant to the question itself.
| Design choice | Who may be missed | Practical improvement |
|---|---|---|
| One daytime location | Evening and off-campus students | Use several times and recruitment channels. |
| Only a voluntary web link | Students with little interest or access | Record how the invitation was distributed. |
| Recruit only friends | People outside your social network | Use a broader invitation route approved for the project. |
What you can responsibly conclude
You can describe what the participating students reported, explain patterns within that dataset and identify questions for further study. You should not claim that the same percentage applies to all students merely because you collected many responses. Recruitment determines which experiences can appear in the data.
If 140 of your hypothetical 200 respondents prefer longer opening hours, write “70% of respondents preferred longer hours,” with the recruitment limitation. Do not silently turn that into “70% of the university’s students want longer hours.” The arithmetic is the same; the population claim is different.
A transparent methods paragraph
Participants were recruited through a convenience sample at the main library entrance during two lunchtime sessions. Eligible participants were currently enrolled students who chose to respond. This approach was feasible within the project timetable, but it may underrepresent evening users and students studying off campus. Findings are interpreted as the views of respondents rather than estimates for the whole university.
Adapt this model only to what actually happened. Add your real eligibility criteria, dates, invitation process, numbers invited where known, responses and ethics arrangements. Do not describe recruitment as random unless you used an actual probability selection procedure.
Convenience or purposive?
If you deliberately seek participants with experience relevant to a defined question, you are using a purposive rationale. If you mainly recruit whoever you can reach, convenience is central. A project can combine both: select a relevant group but access it through a convenient route. Report both decisions instead of choosing the more impressive label.
Checklist before collecting data
- Define the population you want to discuss.
- Write down who your recruitment route can and cannot reach.
- Check consent and ethics requirements.
- Record refusals and missing responses when feasible.
- Plan wording that keeps conclusions within the evidence.
Methodological background: Renjith and colleagues, Qualitative Methods in Health Care Research. The campus scenario and reporting paragraph above are original teaching examples.
Related: Purposive sampling, compare the two approaches, and sampling methods for student research.