The IRAOS is a semi-structured, clinical interview to be used by psychiatrists, psychologists, and other mental health professionals. It has been developed for assessing individual premorbid (social) development, and the onset and course of severe mental disorders (e.g., schizophrenia, affective psychoses). It is of special interest for studying onset, prepsychotic prodrome, and early course in early/detection/early-intervention programs.
The IRAOS is a semi-structured interview originally developed for the assessment of the onset and course of schizophrenia. The current, second version has been extended to encompass all psychotic disorders (affective and non-affective). It is fully compatible with the first version and has been supplemented by data from the population-based ABC Schizophrenia Study -- 232 first illness episodes of schizophrenia. 130 of these cases were compared with 130 age- and sex-matched "healthy" controls from the same population of origin and with 130 age- and sex-matched controls first admitted with a depressive episode. The IRAOS consists of sections on socio-demographic variables (life history data on school education, vocational training, income and living situation, information about family history, pre- and perinatal complications, partner), morbidity status, treatment patterns, and symptom development (date of onset, remission, relapse, and course of 125 indicators of beginning psychosis).
Reliability tests were performed concerning the assessment of time of occurrence and content of variables: Kappa values and pairwise agreement rates were used on socio-demographic data, treatment data, and symptom onset and accumulation. A test-retest analysis was additionally performed on symptom items. On the whole, the reliability measures proved to be sufficiently high.
Symptom selection was based on the literature and, as far as prodromal signs in particular were concerned, on a large-scale expert rating. Besides the tests of face and content validity, in a further test of validity the main indicators of symptomatology and course as well as behavioral variables were compared across three independent data sources: the patient, a key person (relative), and medical records (mostly from primary care physicians/general practitioners). Assessments concerning the time of first-ever occurrence of symptoms (negative, positive, behavioral, etc.) in particular did not differ much, with patient and key person interviews yielding almost identical data. The reliability measures were sufficiently high. According to physician and other records, symptom onset occurred several months later than what the patients and key persons reported.
There are baseline values on social development, utilization patterns and symptoms for a clinical control group (first hospitalized depressive patients) and controls from the general population, matched by age and sex to a sample of 130 schizophrenic patients at first hospitalization.
Duration depends on the complexity of the individual’s biography, age, and ability to concentrate. Mean duration is 1.5-2 hours per interview, and about the same amount of time is needed for coding the information.
In use since 2004.