Types of interviews

Interviews are a form of self-report where researchers ask questions to collect detailed information from participants. They can vary in structure, allowing for different levels of flexibility in the questioning process.

Structured interviews

Structured interviews involve a fixed set of pre-prepared questions that every participant receives in the same order.

Evaluation of structured interviews:

• Strength - Increases reliability because all participants answer identical questions, making comparisons straightforward.
• Weakness - Limits participants' ability to elaborate on answers, potentially missing nuanced insights.

Unstructured interviews

Unstructured interviews have no pre-set questions; instead, the discussion develops naturally based on participants' responses.

Evaluation of unstructured interviews:

• Strength - Provides flexibility to explore topics in depth, allowing researchers to gain unexpected insights without being constrained by a rigid format.
• Weakness - Carries a higher risk of researcher bias, as the interviewer's preconceptions might influence the direction of questions.

Semi-structured interviews

Semi-structured interviews combine elements of both structured and unstructured approaches, with some pre-prepared questions alongside opportunities for open-ended discussion.

Evaluation of semi-structured interviews:

• Strength - Balances standardisation with flexibility, enabling researchers to gain insight into the area.
• Weakness - Still susceptible to researcher bias, particularly in the unstructured portions, which can affect the objectivity of the data.

Methods of accessing participants for interviews

The way researchers conduct interviews can influence participation rates, data quality, and practicality. Common methods include telephone and face-to-face approaches, each with unique advantages and challenges related to accessibility and interaction.

Telephone interviews

Telephone interviews involve conducting the conversation over the phone, without visual contact.

Evaluation of telephone interviews:

• Advantages - Often quicker and more cost-effective, as no travel is needed; suitable for reaching participants in remote locations.
• Disadvantages - Some participants may feel uncomfortable discussing sensitive topics without face-to-face rapport, leading to less in-depth responses; lacks non-verbal cues like facial expressions, which can reduce the richness of data.

Face-to-face interviews

Face-to-face interviews occur in person, allowing direct interaction.

Evaluation of face-to-face interviews:

• Advantages - Enables observation of non-verbal communication, such as gestures and posture, which can provide additional insights into emotional states and increase the validity of the data.
• Disadvantages - May be impractical for participants with limited mobility or transport options, potentially excluding certain groups and introducing sampling bias.

Evaluating interviews

Interviews can yield rich data but also face challenges related to bias and participant responses.

Links between interviews and psychological studies

Interviews have been used in various studies to gather post-experiment insights or supplementary data.

Examples of interviews in psychological studies:

• Milgram's obedience study - Conducted interviews with participants afterwards to explore their reasons for obeying authority figures.
• Dement and Kleitman's sleep and dreams study - Occasionally interviewed participants after dream recall to gather details about their experiences.

Introduction to psychometric tests

Psychometric tests are standardised tools designed to measure aspects of the mind, such as personality, aptitude, knowledge, or skills. They assess individual differences by comparing a person's scores to established norms. Standardisation involves testing large samples to determine average scores, creating a normal distribution where scores range from very low to very high. This allows researchers to rank individuals relative to the population.

However, some tests fail to differentiate effectively between people, leading to issues like ceiling effects or floor effects.

Ceiling and floor effects in psychometric tests

• Ceiling effect - Occurs when most scores are very high, preventing further differentiation as participants cannot score higher; this reduces validity by limiting ranking.
• Floor effect - Happens when most scores are very low, similarly restricting differentiation and validity; for example, an intelligence test that is too difficult would create a floor effect.

To avoid these, tests must be appropriately challenging - not too easy (to prevent ceiling effects) or too hard (to prevent floor effects).

Evaluating psychometric tests

Psychometric tests provide objective data but can be influenced by external factors.

Links between psychometric tests and psychological studies

Psychometric tests are often integrated into studies to measure specific traits or abilities.

Examples of psychometric tests in psychological studies:

• Baron-Cohen et al.'s Eyes Test study - Used the Revised Eyes Test as a psychometric tool to assess theory of mind, which is the ability to understand others' mental states.
• Perry et al.'s personal space study - Employed the Interpersonal Reactivity Index to measure empathy levels, helping to correlate empathy with personal space preferences.