A wide range of research methods are used in psychology. These methods vary by the sources of information that are drawn on, how that information is sampled, and the types of instruments that are used in data collection. Methods also vary by whether they collect qualitative data, quantitative data or both.
Qualitative psychological research is where the research findings are not arrived at by statistical or other quantitative procedures. Quantitative psychological research is where the research findings result from mathematical modeling and statistical estimation or statistical inference. Since qualitative information can be handled as such statistically, the distinction relates to method, rather than the topic studied.
There are three main types of psychological research:
The following are common research designs and data collection methods:
Research designs vary according to the period(s) of time over which data are collected:
Research in psychology has been conducted with both animals and human subjects: