idiographic & nomothetic approaches

idiographic approach

• Idiographic research tends to favour qualitative methods such as case studies which allow the researcher to use a range of methods to create a complete picture of the participant - METHOD TRIANGULATION

• Idiographic research uses small samples, often only a single participant

  • This is done to generate data which is rich and insightful

  • Idiographic researchers are more interested in the why than what of behaviour

• Research within the humanistic approach is idiographic as it seeks to understand the journey taken by an individual

  • EX: use of Maslow’s hierarchy to chart individual progress, Rogers’ client-centred therapy

example of idiographic approach in psychological research

• The case of HM is an example of longitudinal research into the case of an individual with brain damage and resulting anterograde amnesia, using a range of measures e.g:

  • Interviews with HM, his family, the medical staff who attended him

  • A star-tracing task to investigate procedural memory

  • General observations of his behaviour

  • MRI scans to determine the nature of the brain damage

strengths of idiographic approach

• The idiographic approach provides a comprehensive, global understanding of the individual

  • This level of detail can lead to better insight into the complex and multi-layered nature of individual experience

  • Such insight can subsequently inform therapies designed to suit individual needs e.g. psychotherapy or Roger’s client-centred approach

• The idiographic approach is a way to reinstate the human as the focus of psychological research (whereas nomothetic methods tend to ‘banish’ the individual from the process of science)

  • This gives the idiographic approach high ecological validity

weaknesses of idiographic approach

• It is not possible to generalise the findings from idiographic research to general populations due to the restricted sample size and unique and subjective nature of idiographic studies

  • This limits the overall usefulness of the research

• The methods used to study single individuals tend to be subjective which means that they may be prone to various forms of bias e.g:

  • Researcher bias

  • Confirmation bias

  • Bias means that the research may lack credibility

nomothetic approach

• Nomothetic research aims to investigate groups of people to be able to generalise the findings

  • This, in turn, can lead to the establishment of general laws of behaviour

  • Nomothetic research seeks to find similarities between people, what it commonly experienced by the majority

• Nomothetic research tends to favour scientific methods such as lab experiments which involve high levels of control

• Nomothetic research aims to use large sample sizes to generate robust quantitative data which can withstand statistical analysis e.g:

  • Bouchard’s (1990) study on genetic inheritance and IQ used 1,500 pairs of twins and over 350 adopted and biological siblings

  • Van Ijzendoorn & Kroonenberg (1988) collected data on 1,990 participants in cross-cultural replications of Ainsworth’s research

strengths of the nomothetic approach

• Being able to establish general laws of behaviour and compare groups of people is useful in terms of predicting behaviour e.g:

  • A questionnaire on post-natal depression can help to identify women who may need medication and/or counselling

    • As symptoms of depression tend to be similar per person (e.g. low mood, lack of motivation), this enables practitioners to recognise the signs early and take remedial action

• Nomothetic research uses the features of science in its methodology

  • This means that studies are controlled, objective, standardised

  • Therefore nomothetic research has good reliability

weaknesses of the nomothetic approach

• The nomothetic approach can highlight the ‘what’ of behaviour but not the ‘why’

  • A large data set cannot explain the subjective experience of the individual which may be more important and useful than a statistically significant result, particularly when it comes to the understanding of mental illness

  • This means that nomothetic research lacks external validity

• Samples in psychological research are not always large enough from which to generate laws of behaviour e.g:

  • Milgram’s (1963) obedience study used only 40 participants so it would be unwise to state that this sample and the study findings are at widely generalisable