reliability

• Reliability

  This is a measure of consistency. If a particular measurement is repeated and the same result is obtained then that measurement is described as being reliable.
• Ways of assessing reliability

  Test retest - test the same person twice

  Inter observer - compares observations from different observers.

  Correlation - in test retest and inter observer reliability, the two sets of scores are correlated.The correlation coefficient should exceed +0.8 for reliability.
• Improving reliability

  Questionnaires - researcher can replace open questions with closed questions which may be less ambiguous

  Interviews - Use the same interviewer each time but if this is not possible then all interviewers should be trained.

  Observations - Operationalised behavioural categories and must be measureable.

  Experiments - Standardised procedures should be used.