Validity (AQA A-Level Psychology): Revision Notes
Validity
What is validity?
Validity refers to whether a psychological test, observation, or experiment produces results that are legitimate and meaningful. It addresses two key questions: does the research measure what it claims to measure, and can the findings be applied beyond the specific research context?
Validity is distinct from reliability. A study can produce consistent results (high reliability) but still lack validity.
Examples of Reliability Without Validity:
Faulty Scales: Scales might consistently show someone's weight as 7lbs heavier than their actual weight - the readings are reliable but not valid.
IQ Testing: An IQ test might consistently measure someone's familiarity with test formats rather than their actual intelligence.
Types of validity
Face validity
Face validity represents the most basic form of validity assessment. Researchers examine whether a measure appears to assess what it claims to measure at surface level. This involves scrutinising the measuring instrument or having an expert review it.
Face Validity Assessment: Does an anxiety questionnaire actually look like it measures anxiety symptoms? An expert would review the questions to ensure they appear relevant to anxiety measurement.
Concurrent validity
Concurrent validity examines how closely a new psychological measure correlates with existing, established measures of the same construct. When developing a new intelligence test, researchers would compare participants' scores with their performance on well-established tests like the Stanford-Binet test.
High concurrent validity is indicated when the correlation between the two sets of scores exceeds +0.80, showing strong agreement between measures.
Ecological validity
Ecological validity concerns whether research findings can be generalised from the study setting to real-world, everyday situations. This type of external validity is often misunderstood by students who assume that more natural settings automatically produce higher ecological validity.
Common Misconception: The naturalness of the setting alone doesn't determine ecological validity. The key factor is mundane realism - whether the task participants perform resembles activities they would encounter in daily life.
Mundane Realism in Practice: A laboratory study using everyday tasks (like remembering a shopping list) may have higher ecological validity than a field study using artificial tasks.
Temporal validity
Temporal validity addresses whether research findings remain applicable across different historical periods. Some psychological concepts may reflect the cultural and social context of their time rather than universal truths.
Early conformity studies like Asch's experiments may have reflected particularly conformist attitudes in 1950s America, whilst some of Freud's theories about gender differences may reflect Victorian social attitudes rather than timeless psychological principles.
Internal validity
Internal validity refers to whether the observed effects in an experiment can be attributed to the manipulation of the independent variable rather than other confounding factors. A major threat to internal validity occurs when participants respond to demand characteristics - acting in ways they believe are expected rather than behaving naturally.
Demand Characteristics in Research: Critics of Milgram's obedience studies argued that participants may have been 'playing along' with the experimental situation rather than genuinely believing they were administering electric shocks, thus responding to the perceived demands of the situation.
Improving validity
Experimental research
Several techniques can enhance validity in experimental studies:
- Control groups allow researchers to determine whether changes in the dependent variable result from the independent variable manipulation rather than other factors
- Standardised procedures minimise the impact of participant reactivity and investigator effects
- Single-blind procedures prevent participants from knowing the study's aims, reducing demand characteristics
- Double-blind procedures involve a third party conducting the investigation without knowing its main purpose, eliminating both demand characteristics and investigator effects
Questionnaires and psychological tests
Validity in questionnaires can be improved through several methods:
Key Techniques for Questionnaire Validity:
- Lie scales assess the consistency of respondents' answers and help control for social desirability bias
- Anonymity assurances encourage more honest responses by guaranteeing confidentiality
These measures help researchers identify participants who may be responding in socially acceptable ways rather than truthfully.
Observational research
Observational studies can achieve high ecological validity when researchers minimise their intervention. Covert observations are particularly valuable as the behaviour observed is likely to be natural and authentic.
Researchers must ensure that behavioural categories are clearly defined and not too broad, overlapping, or ambiguous, as poorly defined categories can negatively impact the validity of collected data.
Qualitative research methods
Qualitative approaches often demonstrate higher ecological validity than quantitative methods because they capture the depth and detail of participants' experiences through techniques like case studies and interviews, which better reflect participants' reality.
Researchers must establish interpretive validity - ensuring their interpretation of events matches participants' own understanding. This can be achieved through:
- Coherence between the researcher's reporting and participants' actual words
- Direct quotes from participants within research reports
- Triangulation - using multiple sources of evidence (interviews with friends and family, personal diaries, observations) to verify findings
Key Points to Remember:
- Validity concerns whether research measures what it claims to measure and whether findings can be generalised beyond the study context
- Four main types exist: face validity (surface appearance), concurrent validity (comparison with established measures), ecological validity (generalisation to real-world settings), and temporal validity (generalisation across time periods)
- Internal validity focuses on whether observed effects are due to the independent variable manipulation rather than confounding factors
- Ecological validity depends on mundane realism (everyday-like tasks) rather than just natural settings
- Multiple techniques can improve validity, including control groups, standardisation, blinding procedures, and triangulation in qualitative research