Which of the following principles is not included in psychiatric classifi catory systems (ICD and DSM) to define specific psychiatric disorders?
D. In general, both DSM and ICD use symptom count, age of onset, duration, impairment, and exclusion criteria for many psychiatric diagnoses. Aetiological information and theoretical speculations are avoided in classification. Course specifiers are used often in DSM-IV to aid in subtyping a disorder. Good or poor prognostic typology is not employed as a classification principle in either of these systems.
Reference:
Which of the following is a difference between DSM-IV and ICD-10?
D. In DSM-IV a period of at least 6 months of observation is required before a reliable diagnosis of schizophrenia could be made. In ICD-10 a period of 1 month is used instead. This makes DSM-IV schizophrenia narrower than ICD-10 schizophrenia. Schizotypal disorder is a personality disorder according to DSM-IV not ICD-10. Culture-bound syndromes are separately coded in DSM, which is largely an American system. ICD-10 encompasses cultural differences in various places throughout the text.
In the multiaxial system of DSM-IV, the fifth axis refers to:
C. DSM is multiaxial – it consists of five axes:
Note that ICD-10 also has a multiaxial version, which has three axes.
Two clinicians using the same checklist to aid clinical description come up with the same diagnosis.
Which of the following properties of the checklist is involved in this outcome?
B. Reliability of a test refers to its ability to produce the same results when tested at different times (test–retest reliability) or tested by different observers at the same time (observer reliability). Validity refers to the ability of a test to measure what it sets out or intends to measure. Sensitivity refers to the ability of a test to pick the highest number of true patients from a sample to whom it is administered. Specificity refers to the ability to identify the correct diagnosis among various different possibilities. Reliability of diagnostic classifications is enhanced by using operationalized check lists. Field trials enhance the validity. Reliability and validity need not always correlate. It is possible for many clinicians to make the same diagnosis which is not really right (reliable but invalid). Validity has a ceiling set by reliability – very low reliability can reduce validity though vice versa is not true.
Which of the following could increase the validity of psychiatric diagnosis in the future?
B. How can we know whether the diagnosis we make using a set of descriptions and observation is the true condition that a patient has? Cross-sectional studies of even a huge number of patients cannot answer this question. Longitudinal study of the patient in question can improve claims about a diagnosis – but classification systems are typically constructed to enable a clinician to make a diagnosis after a time-sliced, cross-sectional interview rather than a lifelong observation. We can ensure that everyone makes the same diagnosis by having a consensus statement or cross-cultural studies. Definite laboratory measures that are objective can, if developed, increase the validity of a diagnosis.