This article is part of the Iris Ethics Knowledge Base; you can find a directory of all articles here.
The requirement for voluntary participation
The National Statement states that "a person's decision to participate in research is to be voluntary, and based on sufficient information and adequate understanding of both the proposed research and the implications of participation in it" (NS 2.2.1). Voluntary participation is a fundamental ethical requirement, not a procedural formality.
NS 2.2.9 is explicit: "No person should be subject to coercion or pressure in deciding whether to participate. Even where there is no overt coercion or pressure, consent might reflect deference to the researcher's perceived position of power, or to someone else's wishes." A person should be included as a participant only where their consent is voluntary in this fuller sense, not merely where they have not been overtly compelled.
Sources of coercion
Coercion may arise from various sources in applied research and evaluation settings:
- Authority relationships: where a researcher, evaluator, or the commissioning organisation holds a position of authority over potential participants (employer, teacher, healthcare provider, government official), the relationship may make declining difficult even if participation is formally described as voluntary. The National Statement addresses dependent or unequal relationships specifically in Chapter 4.4 and requires particular attention to consent processes in these contexts (NS 3.1.17(d)).
- Incentives: excessive payments or incentives can constitute undue inducement, making it difficult for participants to make a free decision about participation. The National Statement requires researchers and reviewers to consider whether any payment, to participants or to others involved in recruitment, could pressure people to consent, particularly where the research involves more than a lower risk of harm (NS 3.1.21; NS 2.2.10–2.2.11). See Payments and incentives.
- Institutional pressure: in organisational research, including employee surveys and workplace evaluation, pressure from employers or institutions to participate, even informal pressure, undermines voluntary participation. Participation rates should not be monitored or reported in ways that may generate social pressure to take part.
- Relationship-based referral: where existing participants are asked to refer people in their networks, the referred individual may feel a social obligation to participate because of their relationship with the referrer. This falls short of overt coercion but can still affect the voluntariness of a decision to take part; see Snowball sampling.
- Lack of information about alternatives: participants must understand they have a genuine right to decline without disadvantage. NS 2.2.19 states that people who decline need not give reasons for their decision and should suffer no disadvantage as a result.
Managing coercion risks
Strategies for managing coercion risks include: independent administration of research in organisational settings (for example, using a third-party survey platform rather than a manager collecting responses directly); clear information about the right to decline and withdraw at any stage; avoidance of participation tracking that could expose who has and has not taken part; separation between researchers and authority figures where possible; and, for referral-based recruitment, minimising the information shared about a potential participant and giving them a clear, immediate way to opt out of contact.
Reviewers assess coercion risk in the context of the specific relationship and setting, not against a general assumption that any authority relationship makes participation involuntary. The relevant question is whether the design of the project, taken as a whole, gives potential participants a genuine and unpressured choice (NS 2.2.9; NS 3.1.20).
What reviewers look for
Reviewers assess coercion risk against the specific relationship structure and setting described in the application, not against a checklist. In market research and program evaluation, reviewers typically look for: who is delivering the invitation to participate, and whether that person has authority over the potential participant; whether declining is described as consequence-free, and whether that is credible given the setting; whether payment levels are proportionate to burden (see Payments and incentives); and whether the application anticipates specific dependent relationships relevant to the population, such as employer-employee, teacher-student, or service provider-client. Applications that acknowledge these relationships and describe concrete mitigations, rather than simply asserting that participation is voluntary, are easier to assess and approve.
Related resources
- Payments and incentives: where incentives risk becoming undue inducement
- Recruitment strategies: designing an approach to participants that supports voluntary participation
- Snowball sampling: relationship-based pressure in referral recruitment
- When consent can be waived: alternatives where standard consent processes are not practicable
This page was last updated on 16 September 2026.
Was this helpful? We'd appreciate your feedback!
This article makes reference to the National Statement on Ethical Conduct in Human Research 2025. It is intended as practical guidance and does not constitute legal advice.
AI Disclosure: Resources in this library were prepared using Large Language Models with input from Iris Ethics staff who guided the scope and design. Subsequent revisions and final versions were developed and approved by Iris Ethics staff.