The fixed practical

This practical uses an interview, a research method where a researcher asks participants questions and records their responses as psychological data. It must take place in the context of health and well-being. This method–context pairing is fixed: an interview practical cannot be moved to human development, human relationships, or learning and cognition.

The minimum sample is:

• one participant for an individual interview; or
• three to eight participants in one focus group.

Simply having a conversation isn’t enough. A defensible practical starts with a psychological question, then uses a suitable interview format and an appropriate sample. It also needs an ethical, sufficiently consistent procedure. Any conclusions must stay within the limits of what the interview evidence can support.

Choosing the interview format

A structured interview is an interview in which every participant receives the same predetermined questions, usually in the same order and with limited deviation. Because the procedure is standardized, responses are easier to compare and there is less variation caused by the interviewer. However, unexpected but relevant answers may go unexplored.

A semi-structured interview is an interview guided by prepared questions, but the interviewer may ask follow-up questions or change the order when clarification is needed. This gives some consistency while allowing greater depth. On the other hand, different follow-up questions can make responses less directly comparable and give the interviewer more influence.

A focus group is an interview conducted with several participants together. Responses develop through the researcher’s questions and through interaction among group members. This can reveal agreement, disagreement and contrasting perspectives efficiently. Group dynamics can also cause problems: dominant participants may steer the discussion, quieter people may contribute less, and participants may hide sensitive information in front of others.

The psychological question should determine the format. If the question requires comparable responses, a structured interview may work best. If it explores how a participant understands an experience, a semi-structured format may be more suitable. A focus group fits when interaction can reveal useful views, as long as the topic is appropriate for group discussion.

Question wording forms part of measurement, the process of representing a psychological characteristic or experience through recorded evidence. Questions should be clear and relevant, not leading, double-barrelled or built around an unspoken assumption. Asking why an experience was harmful, for example, presupposes that harm occurred. A more open question first lets the participant characterize the experience.

Distinguishing interviews from other research methods

Choose the method because it suits the question, not simply because it is convenient.

• A case study is an intensive investigation of one case or a small bounded set of cases using detailed evidence. It can offer contextual depth, although unusual cases may not represent a wider population.
• A correlational study is a research method that measures the relationship between variables without manipulating them. It can identify an association, but the association alone does not establish a causal relationship.
• A survey or questionnaire is a research method in which participants respond to a standardized set of written or digitally presented items. It can reach many people efficiently, while an interview usually allows more clarification and elaboration.
• An observation is a research method that records behaviour as it occurs instead of relying primarily on participants’ reports. A naturalistic observation takes place in the usual setting, while a controlled observation occurs under researcher-arranged conditions. In an overt observation, participants know they are being observed; in a covert observation, they do not. A participant observation involves the researcher joining the activity being studied, whereas a non-participant observation keeps the researcher outside it.
• An experiment is a research method in which the effect of an independent variable on a dependent variable is investigated under specified conditions. A true experiment assigns participants to conditions through a random process, whereas a quasi-experiment uses a pre-existing characteristic or grouping that the researcher cannot randomly assign.

Interviews are especially useful when investigating reported meanings, perceptions and experiences. Unlike experiments, they normally don’t manipulate an independent variable or control alternative explanations strongly enough to demonstrate causation.

Sampling

A sample is the group of participants from whom research data are collected. Sampling choices shape who is represented and which perspectives are missing. They also affect how far findings can reasonably extend beyond the people interviewed.

• Random sampling is a sampling technique in which each member of the target population has a known and equal chance of selection. It can reduce systematic selection bias, but it requires access to an adequate population list. With a small sample, chance may still produce an unbalanced group.
• Stratified sampling is a sampling technique that selects participants from defined population subgroups in planned proportions. This can improve representation of relevant subgroups, but the researcher must know the population structure and decide which characteristics matter.
• Opportunity sampling is a sampling technique that recruits people who are available and accessible to the researcher. It is practical, though accessibility may create a narrow or systematically biased sample.
• Self-selected sampling is a sampling technique in which people choose to participate after encountering an invitation. It respects voluntary participation and can attract interested participants. However, volunteers may differ from people who do not respond.
• Snowball sampling is a sampling technique in which initial participants help identify or recruit further participants. It may give access to populations that are difficult to reach. However, the resulting participants often belong to connected social networks and may be unusually similar.

Meeting the numerical minimum does not automatically make the sample representative. A one-person interview can provide depth, but it cannot show how common that person’s account is. A focus group includes several perspectives, yet its participants still make up a small, socially interactive sample.

Ethics in a health and well-being interview

Ethical considerations are principles used to protect participants, researchers and others affected by psychological research. They shape recruitment, the questions that may be asked and the way responses are recorded and reported.

Participants should volunteer on the basis of adequate information and understand that they may withdraw. They must also be protected from unnecessary distress. Researchers should handle private information confidentially and remove details that could identify a participant when reporting it. Recording requires clear agreement, and participants should receive an appropriate explanation when their participation ends.

Such protections can change the research design. A researcher might remove a highly intrusive question even if it could produce interesting data. Participants should be free to skip questions, although the resulting missing responses can reduce comparability. The interviewer may also need a plan to pause or end the interview if a participant shows discomfort.

Focus groups need an extra warning. A researcher can promise to handle information responsibly, but cannot guarantee that other participants will keep the discussion confidential. Participants should be told about this limitation beforehand. Questions about health and well-being must therefore suit a group setting rather than simply being transferred from an individual interview schedule.

Bias and reflexivity

A bias is a systematic influence that shifts evidence or conclusions away from an adequately balanced representation. A difference of opinion is not automatically a bias.

Researcher bias is a systematic influence arising from the researcher’s expectations, decisions or behaviour. An interviewer’s tone of voice can shape an interview, as can selective follow-up questions or greater attention to answers that match an expectation.

Participant bias is a systematic change in participants’ responses caused by their interpretation of the research situation or their wish to present themselves in a particular way. During a health and well-being interview, a participant might minimize or exaggerate an experience. They might also agree with the interviewer or give an answer viewed as socially acceptable.

Reflexivity is the process through which researchers examine how their own position, expectations and decisions may influence the research. It helps them check for unconscious bias instead of pretending that an interviewer can be completely neutral.

In practice, a researcher could record why each question was phrased in a particular way and note when follow-up questions departed from the plan. They should also consider whether the interviewer reacted differently to different answers. Reflexivity should produce an honest evaluation of influence; merely acknowledging bias does not remove it.

External variables and causal conclusions

An external variable is a factor outside the relationship of primary interest that may influence the data. In an interview, this could include the setting, time available, presence of other people, interviewer manner, participant mood and perceived privacy.

Keeping the procedure consistent can reduce some of this variation. Using the same introduction, a similar setting, a consistent recording method and neutral prompts makes it less likely that responses differ just because the interviews were conducted differently. Complete standardization is not possible in semi-structured interviews or focus groups, so important differences should be documented.

Causality is a relationship in which a change in one factor produces a change in another. Interview evidence can suggest explanations or perceived influences, but a participant’s belief that one event caused another does not establish causality. An unmeasured third factor may be involved, the direction of influence may be unclear, or the participant’s memory may be inaccurate. Conclusions should describe accounts, perspectives or possible relationships rather than claim a demonstrated cause.

Validity and reliability

Validity is the extent to which evidence and conclusions adequately represent what the research claims to investigate.

• Internal validity is the extent to which a study supports its conclusion about what produced the observed result. In an interview, it is limited when external variables or alternative explanations remain uncontrolled.
• External validity is the extent to which findings apply beyond the particular research conditions. An artificial setting or unusually formal interaction may make interview responses less representative of other settings.
• Content validity is the extent to which the questions adequately cover the relevant parts of the topic. An interview about well-being may have weak content validity if it focuses on only one narrow aspect.
• Face validity is the extent to which a measure appears, on reasonable inspection, to address what it claims to measure. Questions that are clear and obviously relevant can support it, although appearance alone does not establish stronger forms of validity.
• Construct validity is the extent to which a method adequately represents the psychological construct it is intended to investigate. The interview questions and their interpretation must match the meaning of the construct rather than measure a convenient substitute.

Reliability is the extent to which a method produces consistent evidence when the relevant conditions are repeated or when different researchers handle the same material. Reliability can improve through structured questions, a consistent procedure, accurate recording and clear decision rules. Still, very rigid standardization may reduce the depth that makes interviews valuable. Reliability and richness need to be balanced rather than treated as the same goal.

Validity and reliability are connected, but they are not interchangeable. A consistently leading question may produce similar answers and therefore seem reliable, while still failing to measure participants’ views validly.

Generalizability, transferability and credibility

Generalizability is the extent to which findings from a sample can be applied to a wider population or set of contexts. It depends on the sampling method and sample composition, as well as the sample size, research setting and consistency of the pattern found. The small minimum sample required for this practical makes broad statistical generalization especially difficult.

Before applying findings to another population or context, consider whether the people and setting are sufficiently similar. Social expectations and the meaning of health and well-being also matter. A conclusion drawn from one participant should not be written as though it automatically describes everyone.

Transferability is the extent to which findings may be relevant to another population or context after similarities and differences between the original and new situations have been examined. Instead of claiming universal application, the researcher gives enough contextual detail to support a reasoned judgment about whether the account transfers.

Credibility is the extent to which an interpretation is well supported by the evidence and presents a convincing account of participants’ perspectives. Researchers can strengthen it by keeping an accurate record and grounding interpretations in what participants actually said. They should also consider responses that do not fit the main pattern, document research decisions and use reflexivity to examine bias.

Generalizability and transferability address different questions. Generalizability asks how far a finding extends across a wider population or context. Transferability asks whether insight from one setting can meaningfully apply to another after the contexts have been compared.

What a defensible write-up contains

A write-up of an interview practical should show the chain of reasoning clearly:

1. identify the psychological question within health and well-being;
2. justify the choice of structured interview, semi-structured interview or focus group;
3. state the sample and sampling technique, showing that the required minimum was met;
4. describe the questions, procedure and recording method clearly enough for the process to be understood;
5. explain how ethical considerations affected the design;
6. present conclusions that remain grounded in the interview material;
7. evaluate bias, reflexivity, external variables, validity and reliability; and
8. judge generalizability or transferability without making claims that exceed the sample and method.

The strongest accounts connect each decision to what it changes. Identical questions, for example, may improve reliability and comparability but limit elaboration. Flexible follow-ups can deepen understanding, though they also increase interviewer influence. Don’t just label an advantage or limitation—explain its effect on this particular interview design.