Meta-analysis (AQA AS Psychology)

Meta-analysis

• A meta-analysis is a quantitative research method which takes data from published studies

  • Other researchers have conducted the research and published the results e.g.

    • a meta-analysis of 133 studies to investigate cultural variations in conformity

    • a meta-analysis of 32 cross-cultural replications of the Strange Situation

• A meta-analysis procedure involves a statistical calculation of the numerical findings of lab experiments, correlational studies and questionnaire-based research

  • The meta-analysis may use data from only one method e.g. lab experiments or from more than one method

• Researchers combine the findings from these multiple studies to draw an overall conclusion about the topic

• The results of a meta-analysis are expressed in terms of effect size

  • effect size refers to the strength of the relationship between two variables on a numeric scale e.g.

    • the effect size for cognitive behavioural therapy as a treatment for anxiety is 0.92 which is a large effect size

• A meta-analysis allows for trends/patterns to be identified by combining the data of lots of smaller studies

• Such trends would not be identifiable if only one study at a time was analysed

Evaluation of meta-analysis

Strengths

• There is less chance of bias confounding the results due to the use of secondary data

  • The researchers have not carried out the research themselves so they cannot have influenced the outcome in any way

  • This increases the reliability of the findings as a large number of studies analysed statistically increases the robustness of data (known as statistical power)

• It is possible to generalise the findings to a wider population due to the number of studies included in the meta-analysis

  • This increases the external validity of the findings

Limitations

• The use of secondary data means that the researchers cannot be 100% confident as to the degree of precision exercised by the original researchers

  • They have no control over how key variables are operationalised

  • This limits the reliability of the findings to some extent

• It may be difficult for the researcher to access relevant studies

  • This means that the process can be time-consuming and rather onerous

  • This could lead to the researcher abandoning the research which is a limitation as valuable insight into a topic could then be lost