Validity

• Validity

  Whether a psychological test/observation measures what it is designed to measure
• Internal validity

  The degree to which the effects observed in an experiment are due to the independent variable and not confounds and whether the researchers managed to measure what they intended.
• External validity

  Extent to which we can generalise findings to real-world settings. Relates to factors outside of the investigation: generalising to other settings, other populations of people and other eras.
• Ecological validity


  Concerns generalising findings from one setting to the other settings- most particular to 'everyday life'. However, tasks of the experiment are also important and if the task that is used to measure the dependent variable is not like everyday life (low mundane realism), there is low ecological validity.
• Temporal validity

  The issue of whether findings from a particular study or concepts within a particular theory hold true over time.
• Face validity

  Measures whether a test looks like it tests what it is supposed to test and whether a test, scale, measure appears 'on the face of it' to measure what it is supposed to measure.
• Concurrent validity

  When a particular test/scale demonstrates very close, or matched, results to a well-recongised and established test.
• Improving validity in Experimental research

  control group can help assess whether changes in the dependent variable were due to the effect of the independent variable. Standardised procedures can also be used to minimise the impact of ppt reactivity and investigator effects on the validity of an outcome. This can additionally be achieved by single-blind and double-blind trials as demand characteristics are reduced.
• Improving validity in Questionnaires

  The use of lie scales and anonymity can assess the consistency of a responsdent's answers and reduce social desirability.
• Improving validity in Observations

  Obserbational research has good ecological validity as there may be minimal intervention from the researcher. Findings may be even more authentic in covert observations

  Qualitative methods. But, behavioural categories that are too broad, overlapping or ambiguous can negatively impact the validity.
• Improving Validity in qualitative methods

  Researchers still have to show interpretive validity of their conclusions : extent to which researchers' interpretations of events match those of their ppts. This can be demonstrated through things like coherence of the researchers reporting and the inclusion of direct quotes from ppts. Depth and detail may increase validity but further enhanced through triangulation, a use of a number of sources for ecidence which increases validity.