Following on from the common theories in psychology listed in my previous post, this post will summarise the research methods and techniques used in Psychology, according to Psychology by Carlson, Martin and Buskist (2004).
Psychology uses the scientific method, containing three core types of research: observation (in natural environment, e.g. Darwin); correlational studies (observation with formal measurements and examination of relationships between measurements); and experiments (making things happen and observing the results).
Experiments are seen to be the most rigorous, and five stages are described for all research of this nature:
- Identifying the problem and creating a cause-effect hypothesis
- Design the experiment – define the independent and dependent variables
- Conduct the experiment – record observations
- Examine data collected and evaluate hypothesis
- Communicate the results
While observations are commonly used in psychology, it is experimentation that quantifies behaviours and is the only method that can determine whether theories are correct (although the importance of qualitative research has increased since the 1970s). Experiments are likely to include an ‘experimental group’ on which the study is aimed, and a ‘control group’ which is used for comparison and uses techniques such as administering placebos to replicate the conditions of the experimental group (when the research knows who is receiving a placebo, this is called a single-blind study. A double-blind study is when neither the participants nor the researcher knows who is receiving a placebo).
An experiment may use independent groups (between-groups) where each group of participants is tested in a slightly different way, or repeated measures (within-groups) where every participant is exposed to the experiment in the exact same way. Experiments may be classed as laboratory experiments where the researcher is in control over all variables, or field experiments which occur in the natural or normal environment, and in which the research should not interfere.
Whereas my other discipline (anthropology) involved studying a single particular society or community, psychology aims to explain features of behaviour more generally and so research must make use of samples to infer findings across a larger population. Random sampling is typically used. In some scenarios however, single-case study is used to focus on individuals and this uses either experiments or correlational studies. Correlational studies are studies used when there are variables which are needed to be studied but cannot be manipulated by the researcher e.g. social class, income, sex, personality etc.
Some qualitative research used in psychology includes semi-structured interviews, discourse analysis and grounded theory. However qualitative research is still rejected by many psychologists as it is too subjective for this field.