This essay will be a critical evaluation of the diagnosis and classification of abnormality and the intrinsic problems involved. The term ‘abnormality’ is defined as ‘deviation from a norm or standard’, but how do psychologists determine what is abnormal or normal behaviour? The first attempt at classification of psychological abnormality was made by the Greek physician Hippocrates. He identified three categories, mania, melancholia and phrentis (fever of the brain).
The first prevalent classification was developed by Kraeplin (1913) who collated earlier systems and elaborated on them. This then led to classification systems, different models and four definitions of abnormality being developed to define abnormal behaviour however, this is not an infallible system as discussed further on in the essay. Statistical infrequency is based on the idea that if certain behaviour, a person’s personality or ways of thinking are statistically rare or unusual, then it is deemed as abnormal.
They make no value judgements, for example homosexuality is no longer classed as wrong or unacceptable, just less statistically common. Nevertheless, the desirability of certain traits is not taken into account. If a person has a high IQ, they are deemed as ‘abnormal’, however, this should be classed as a gift not an abnormality. It is also thought that some mental illnesses are increasing such as depression, and therefore are not rare and thus not statistically infrequent but are still a problem.
Deviation from social norms is behaviour by people who break the unwritten rules within a certain social group. However, this concept is influenced by culture and era. For instance, 50 years ago couples living together before marriage would have been deemed as socially deviant whereas this is now accepted as the norm. This definition also has to take into account the time and context in which the behaviour occurs. For example, singing loudly in the shower is acceptable whereas singing loudly in the street is not.