Validity

• Internal validity

  • Refers to how true and accurate study is in what it is meant to study
• External validity

  • Refers to whether study is accurate or true within the real world allowing generalisations
• Issues of internal validity:

  • Demand characteristics: participants aware of aims so alter behaviour to prove or disprove study
  • Researcher bias: What investigator does either directly or indirectly affecting preformance
  • Social Desirability bias: respond in a favourable manner
  • Confouding variables
• Issues of external validity

  • Ecological validity: Can we generalise the findings to real life
  • Population validity: Generalise to target population