Psychology-Mental Abnormality

Discuss the issues of Reliability and Validity in the Diagnosis of Mental Abnormality

Diagnosis is the process of identifying a disease, and allocating it to a category on the basis of symptoms and signs.
A classification system such as the DSM-IV version can be used to diagnose mental abnormality. Categorisation therefore is very important, as diagnosis using the classification system will bring about certain treatments, and if the diagnosis is wrong, the person may be receiving inappropriate treatment, which may do more harm than good. Clearly any classification system will be of little value unless psychologists can agree with one another when trying to reach a diagnosis.
However if for example a person is diagnosed with a mental illness such as manic depression, the clinical psychologist will know what symptoms to expect and possible ways of treating the illness. By clinical psychologists all using the same classification system, diagnosis should be less bias, because they us...