Even the best-designed questionnaires with the best psychometric properties cannot be a substitute for a psychiatric interview. Only the latter can obtain the information that leads to a diagnosis, reached according to the international criteria. But for many years, psychiatric assessments were entirely in the hands of the individual clinician. As a consequence, different psychiatrists obtained different information; and different psychiatrists assembled the information in different ways to reach a diagnosis. Not unexpectedly, agreement between interviewers was poor even within one centre, as shown by Kreitman.(38) Progress of fundamental significance for all of psychiatry has been made since the late 1960s with the development of standardized assessments. These are standardized in two mutually complementary ways. First, neither the questions asked nor the ratings of behaviour are left to the idiosyncrasies of the interviewer. Instead, this information variance is reduced by having interviewers ask about symptoms in the same way. Second is the reduction of criterion variance, where the symptoms or signs elicited are, like building bricks, assembled in exactly the same way, both within and across studies. This is achieved by applying to the data an algorithm that is a precise expression of the diagnostic criteria in ICD-10 or DSM-IV. The algorithm can be computerized so that the responses to each item in the interview are assembled automatically. This determines if the person's symptoms and behaviour fulfil the diagnostic criteria. By appropriate programming, a symptom score can also be obtained in addition to the categorical diagnosis.
There are two types of standardized psychiatric examination. This is for the good reason that, although full clinical interviews in the field by experienced clinicians may be the ideal, such resources are often not available. The first type of instrument is designed for use by experienced clinicians after some training. These instruments allow some flexibility in questioning, and enable the clinicians to use their judgement when making a rating about the presence or absence of each symptom or behaviour. The second type of instrument is for use by lay interviewers. These interviews are 'fully scripted', where the questions asked are invariable and must be strictly adhered to, with only very few of the items calling for any judgement. Such instruments can now be computerized for use on a laptop. The scoring of responses is then both error-free and available immediately the interview is completed.
The Schedule for Clinical Assessment in Neuropsychiatry (SCAN) belongs to the first type. It is the successor to the groundbreaking Present State Examination ( PSE) developed by Wing et al.(39) and now revised(40) for the World Health Organization. SCAN is a clinician's instrument because it requires familiarity with the phenomenology of mental disorders. It assumes that the interviewer is comfortable in examining persons with a mental disorder. In complete contrast to interviews for use by laypersons, the clinician asks the main question, but is allowed to probe with further questions if necessary, before deciding if a symptom is present or not. The correct use of SCAN requires formal training in one of the designated centres around the world. SCAN has a number of modules, each dealing with a group of disorders such as anxiety states, affective disorders, substance abuse, or psychoses. It is available from the World Health Organization.
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This guide Don't Panic has tips and additional information on what you should do when you are experiencing an anxiety or panic attack. With so much going on in the world today with taking care of your family, working full time, dealing with office politics and other things, you could experience a serious meltdown. All of these things could at one point cause you to stress out and snap.