Summary

Psychologists carry out research using experimental and non-experimental methods

Experiments are more scientific, but they lack ecological validity

Questioning people can be a useful way to measure opinions.

An interview would allow more depth than a questionnaire, but a questionnaire is easier to administer.

The observational method allows observations of naturally occurring behaviour.

The presence of an observer can change participants’ behaviour.

Case Studies are used when more detail is required or when looking at an unusual case. They are time consuming and lack generalisability.

A correlation indicates whether there is a relationship between 2 variables, but it does not establish cause and effect.