Types of Data

  • Quantitative: Numerical

  • Qualitative: Non-numerical

    • For example, some quantitative data in the Milgram experiment would be how many subjects delivered a lethal shock. In contrast, some qualitative data would be asking the subjects afterwards how they felt about delivering the lethal shock.

  • Primary data: Original data collected for the study

  • Secondary data: Data from another study previously conducted

Content analysis:

  • Although the detail of qualitative data may be valuable, this level of detail can also make it hard to objectively or mathematically analyse. Content analysis is a way of analysing qualitative data. The process is as follows:

    • A sample of qualitative data is collected

      • E.g. A bunch of unstructured interviews on the topic of childhood

    • Relevant coding units are identified and operationalised

      • E.g. Discussion of traumatic events, happy memories, births, and deaths

    • The data is analysed according to these coding units to produce quantitative metrics

      • For researchers listen to the unstructured interviews and count how often traumatic events are mentioned

What is a meta-analysis?

  • It is a study of studies. It involves taking several smaller studies within a certain research area and using statistics to identify similarities and trends within those studies to create a larger study.

    • Examples: Van Ijzendoorn’s meta-analysis of several strange situation studies and Grootheest et al’s meta-analysis of twin studies on OCD.

  • A good meta-analysis is often more reliable than a regular study because it is based on a larger data set, and any issues with one single study will be balanced out by the other studies.