Reliability and validity in diagnosis Flashcards
What does “reliability” mean in a diagnostic system?
Reliability means there is good consistency over time and among different raters. If therapists often disagree on diagnoses, it suggests low reliability.
What does “validity” mean in a diagnostic system?
Validity means the system assesses what it claims to assess. In schizophrenia, it means that those diagnosed with the disorder actually have it.
How are reliability and validity linked in a diagnostic system?
If a diagnostic system has low reliability (i.e., raters disagree), questions about its validity (whether it accurately diagnoses schizophrenia) become meaningless.
What is co-morbidity?
Co-morbidity is the occurrence of two illnesses together, which can confuse diagnosis and treatment.
What is symptom overlap?
Symptom overlap occurs when two or more conditions share similar symptoms, which can call into question the validity of a diagnosis.
What was the procedure of Rosenhan’s study?
Eight confederates (pseudopatients) went to 12 different psychiatric hospitals, pretending to hear voices. They behaved normally once admitted and observed whether staff detected their sanity.
hat were the results of Rosenhan’s study?
Staff diagnosed 11 pseudopatients with schizophrenia, and one with manic-depression. Staff never detected their sanity. The average hospital stay was 19 days.
What conclusion did Rosenhan’s study lead to?
Psychiatric staff cannot always distinguish sanity from insanity, questioning the Rosenhan’s study? There is reliability, but not validity in diagnosis.
What is inter-rater reliability in the context of schizophrenia diagnosis?
Inter-rater reliability refers to the extent to which different assessors agree on the diagnosis of a patient.
What did Cheniaux’s (2009) study show about inter-rater reliability in schizophrenia diagnosis?
The study showed poor inter-rater reliability, with one psychiatrist diagnosing 26 patients with schizophrenia according to DSM and 44 according to ICD, and the other diagnosing 13 and 24, respectively.
How does low inter-rater reliability affect schizophrenia diagnosis?
It suggests that different mental health professionals may not agree on a diagnosis, indicating poor reliability in the diagnostic system.
What is predictive validity in schizophrenia diagnosis?
Predictive validity refers to whether the diagnosis leads to successful treatment and whether it predicts the future course of the disorder.
What did Mason et al. (1997) find about predictive validity in schizophrenia diagnosis?
Mason et al. found that more modern classification systems of diagnosis had high predictive validity, especially when only symptoms lasting over six months were considered.
What did Buckley et al. (2009) find about co-morbidity in schizophrenia?
Buckley et al. found that around half of those with schizophrenia also had depression (50%) or substance abuse (47%), and other disorders like PTSD and OCD were also common.
Why does co-morbidity present a problem in schizophrenia diagnosis?
It suggests that diagnostic tools might not differentiate well between schizophrenia and other disorders, calling into question the reliability and validity of the diagnosis.
What is gender bias in schizophrenia diagnosis?
Gender bias refers to the tendency to diagnose men and women differently based on their symptoms, which can affect the accuracy of the diagnosis.
What did Longenecker et al. (2010) find about gender bias in schizophrenia diagnosis?
Longenecker et al. found that men have been diagnosed with schizophrenia more often than women, possibly due to gender bias or better functioning in women.
How does gender bias affect schizophrenia diagnosis?
Gender bias may lead to under-diagnosis in women, as their better interpersonal functioning may mask symptoms or make their case seem too mild compared to men.
What is culture bias in schizophrenia diagnosis?
Culture bias refers to the way diagnostic systems may reflect western ideas of abnormality, leading to misdiagnosis in individuals from non-western cultures.
How does culture bias affect the diagnosis of schizophrenia?
Cultural beliefs may make certain symptoms (like hearing voices) more acceptable in some cultures, leading to misdiagnosis in others. For example, African Americans are more likely to be diagnosed with schizophrenia due to cultural differences in interpreting symptoms.
What did Escobar (2012) say about culture bias in schizophrenia diagnosis?
Escobar pointed out that predominantly white psychiatrists may over-interpret symptoms in black patients and distrust their honesty, leading to biased diagnoses.
