One issue that arises when considering the classification or diagnosis of schizophrenia is how reliable the major classification systems are ( the DSM and ICD). This is an issue of reliability when diagnosing schizophrenia as it is often argued that the classification systems are not detailed enough to be able to make a definite diagnosis of schizophrenia as they fail to cover a broad range of issues and problems.
It has been argued that due to the differences between the two class systems the diagnosis could be different, for example if one doctor uses the DSM and another doctor uses the ICD. For example the DSM includes 5 subtypes of schizophrenia but the ICD has 7, therefore one patient could fall under different subtypes depending on the classification system used. Copeland supports this as he found when giving 124 US and 194 British psychiatrists a descriptions of a patients, 69% of the US psychiatrists diagnosed the patient with schizophrenia, compared with only 2% of British psychiatrists. The differences in the percentages regarding diagnosis could be due to the fact that the US uses the DSM while in Britain, the ICD is used.
There are also issues with reliability within each classification system. Beck reported that 4 experienced clinicians each relying on the DSM 1, independently interviewed 153 patients who were recently diagnosed to a mental hospital however, only 54% of their diagnoses were in agreement, this was linked to the vague criteria for diagnosis and inconsistencies in techniques to gather data. The low reliability of this system supports the idea that the classification system may be unreliable. However it can also be argued that Beck’s research is outdated, when completing the study he looked at DSM 1, however psychiatrists are now using DSM 5, an update version which includes more detail and operationalised definitions.
A second issue issue that may be associated with the classification and/or diagnosis of schizophrenia is that of validity. Validity may be a problem when the DSM or ICD are being used to classify or diagnose a person as schizophrenic as the symptoms that are written with the DSM or ICD may overlap with other symptoms, causing comorbidity, the symptoms can often be seen to be similar of depression. The causes the validity regarding the way schizophrenia is diagnosed to be questioned, as the classification systems used may lead to a misdiagnosis.
In order to test the validity of these systems Rosenhan (1973) completed a study to illustrate the problems involved in determining normality and abnormality. 8 ‘sane’ people tried to gain permission to 12 psychiatric hospitals. Each ‘patient’ said they had only one symptom, that the heard voices in their heads saying ‘hollow’, ‘empty’ and ‘thud’. 7 out of the 8 ‘patients’ were diagnosed with schizophrenia and admitted to a psychiatric hospital where they spent between 7 and 25 days. This misdiagnosis of ‘sane’ people demonstrates the issues surrounding diagnosis or schizophrenia by using the classification systems DSM and the ICD. However, when the psychiatric hospitals discovered Rosenhans study they were outraged at his findings and challenged him to send more ‘sane’ patients which the argued they would be able to distinguish between ‘insane’