16 marker paragraphs

• A limitation is the low reliability of the diagnosis of schizophrenia. Chiniaux et al had 2 psychiatrists diagnose 100 patients using the DSM and ICD. He found there was poor inter-rater reliability and the findings suggested that the ICD over-diagnosed and the DSM under-

  diagnosed. This inconsistency is a weakness. Moreover, Cheniaux’s study also highlights the issue of validity in the diagnosis. Schizophrenia is more likely to be diagnosed in ICD then DSM. A standard way to assess validity is to see if classification systems arrive at same diagnosis and this is not true for this study which can have an impact on treatment
• Classification of mental disorders is the process of organising the symptoms into categories

  depending on which cluster together in a sufferer. They are two major classification systems;

  ICD-10 and DSM-5 which both differ in their classification of Schizophrenia. For example, in the

  DSM-5, one of the positive symptoms must be present whereas in the ICS-10, two or more

  negative symptoms must be present for diagnosis.
• Another significant issue is symptom overlap with other mental disorders, which undermines the validity of schizophrenia diagnosis. For example, both schizophrenia and bipolar disorder can involve symptoms like delusions and hallucinations, while avolition is also found in depression. This overlap makes it difficult for clinicians to distinguish between disorders, leading to potential misdiagnosis. If two disorders share many symptoms, then it becomes unclear whether they are truly separate conditions or variations of the same underlying problem.This undermines the construct validity of schizophrenia as a distinct disorder. Furthermore, if a diagnosis lacks validity, treatment may target the wrong symptoms or disorder entirely, reducing treatment effectiveness.
• One important issue affecting the validity of schizophrenia diagnosis is gender bias. Research suggests that men are more likely to be diagnosed with schizophrenia than women, even though some studies indicate that women may experience similar rates of the disorder. For example, Longenecker et al. (2010) found that men have been diagnosed more often than women in recent decades, which may reflect a gender bias in diagnosis rather than actual prevalence.
• This bias may occur because clinicians tend to associate schizophrenia more with male behaviour, such as aggression or social withdrawal, and may overlook or misattribute symptoms in women—possibly diagnosing them with depression or anxiety instead.This undermines the validity of the diagnosis, as it means the classification system might be more sensitive to stereotypically male presentations. Furthermore, women tend to function better socially and maintain relationships, which may lead to their symptoms being viewed as less severe or ignored altogether. This gender bias can result in underdiagnosis in females and overdiagnosis in males, meaning that individuals may not receive accurate treatment based on their actual needs.
• Cultural bias is another major factor that reduces the validity of schizophrenia diagnosis. Diagnostic criteria, such as those in the DSM or ICD, are based on Western norms and may not account for cultural differences in behaviour or beliefs. For example, auditory hallucinations or spiritual visions may be considered signs of schizophrenia in Western cultures but are seen as normal or even positive in some non-Western cultures.
• This can lead to overdiagnosis of schizophrenia in ethnic minorities, particularly Black African and Caribbean individuals living in Western countries. Research has found that Black British people are several times more likely to be diagnosed with schizophrenia than White British individuals, despite no evidence of higher rates in their countries of origin.This suggests that cultural misunderstanding by predominantly White, Western clinicians contributes to biased diagnosis. Such bias not only questions the construct validity of the diagnosis but also raises ethical concerns around discrimination and stereotyping. To improve validity, mental health professionals must be trained in cultural competence and diagnostic systems should be adapted to be more inclusive and sensitive to cultural contexts.
• Comorbidity is another factor that reduces the validity of schizophrenia diagnosis. Comorbidity refers to when a person diagnosed with schizophrenia also meets the criteria for other disorders, such as depression, anxiety, or substance abuse. For instance, research has shown that up to 50% of patients with schizophrenia also have a diagnosis of depression.
• This raises the question of whether schizophrenia is a single, distinct disorder, or just one aspect of a broader range of mental health issues. If schizophrenia commonly overlaps with other conditions, it challenges the discriminant validity of the diagnosis.As a result, it becomes difficult to know whether clinicians are treating schizophrenia itself or co-occurring symptoms from other disorders, potentially leading to ineffective or inappropriate treatment plans. Moreover, comorbidity complicates research efforts, as it's unclear whether findings relate to schizophrenia specifically or to overlapping conditions. This suggests the current classification systems may be overly simplistic, and a more holistic or dimensional approach might better capture the complexity of mental illness.
• The diagnosis and classification of schizophrenia raise concerns about both reliability and validity. Reliability refers to the consistency of diagnosis, either across different clinicians (inter-rater reliability) or over time (test-retest reliability). Validity refers to whether schizophrenia is a distinct disorder that is accurately and meaningfully diagnosed. Problems with both reliability and validity can lead to misdiagnosis, inappropriate treatment, and confusion about what schizophrenia actually is.