Validity

Validity

The extent to which an observed effect is genuine.

Does it measure what it was supposed to, and can it be generalised beyond the research setting where it was found?

Concurrent validity

The extent to which a psychological measure relates to an existing similar measure

Ecological validity

The extent to which findings from a research study can be generalised to other settings and situations.

A form of external validity

Face validity

A form of validity where a measure is scrutinised to determine whether it appears to measure what it is supposed to measure.

E.g. does a test of anxiety look like it measures anxiety.

Temporal validity

The extent to which findings from a research study can be generalised to other historical times and eras.

A form of external validity

How to improve validity

Experiments

Questionnaires

Observations

Qualitative research

Experiments

Using a control group makes a researcher better able to assess whether changes in the dependent variable were due to the effect of the IV.

Experimenters may also standardise procedures to minimise the impact of participant reactivity and investigator effects on the validity of the outcome.

Using a single-blind or double-blind procedure is designed to achieve the same aim

Single-blind - Participants are not aware of the aims until they take part.

Double-blind - 3rd party conducts the investigation without knowing the main purpose. Reduces demand characteristics and investigator effects and improves validity.

Questionnaires

Many of these and psychological tests have a lie scale in the questions to assess the consistency of the respondent’s answers and controls for social desirability bias.

Validity can be enhanced by assuring that the respondent’s data is anonymous.

Observations

May produce findings that have high ecological validity as there may be minimal intervention by the researcher. This is true if there is a covert observation so the behaviour of those observed is likely to be natural and authentic.

Behavioural categories that are too broad, overlapping or ambiguous may have a negative impact on the validity of the data collected

Qualitative research

May be higher in ecological validity than quantitative or less interpretive methods of research. This is because the depth and detail associated with case studies and interviews is better able to reflect a participant’s reality.

A researcher may have to determine interpretive validity of their conclusions - The extent to which the researcher’s interpretation of events matches that of their participants. This can be demonstrated through such things as the coherence of the researcher’s narrative and the inclusion of direct quotes from participants in the report.

Validity is further enhanced through triangulation - the use of a number of different sources as evidence, e.g. data compiled through interviews with family and friends.