The diagnostic process in psychiatry has traditionally relied on gathering information through individual history-taking and clinical examination. When operationalising the concepts involved in order to be able to exploit the opportunities offered by computers it is important to understand clearly what their advantages and disadvantages are compared with human beings (Conrad, 1993). Humans are unmatched in pattern recognition, decision-making and clinical administration. Computers excel at repetitive and conceptually trivial tasks such as recording and retrieving numbers and text, and can provide high-speed analyses of the relationships between data. The development of comprehensive systems to aid the systematic and reliable collection of clinical data, to which specific algorithms can be applied to ensure the comparability of classifications, has been described in earlier chapters. Instruments such as SCAN, CIDI and IPDE are the most recent and complete examples. The three key components that current computer technology provides are database, graphical display and multimedia recording and playback function (Dittman, 1991; Sartorius et al., 1993; Üstün and Tien, 1995). These are summarised below and expanded later in the chapter.
Database: SCAN allows complex data interactions to be recorded, e.g. between defined clinical symptoms, their severity and their time relationships, thus facilitating further refinements and developments.
Graphics: Human abilities in pattern recognition and decision-making can be substantially enhanced by employing computers to display information from the database graphically. For example, a chart showing longitudinal data from repeated assessments of a patient can reveal patterns of temporal association between specific symptoms of depression and varying levels of alcohol misuse. Graphical display of this information can be useful, not only to the clinician, but also for the patient. The computer can also display the structural details of the algorithms, facilitating more widespread understanding and further developments of consensus.
Multi media facilities: Training interviewers and ensuring reliability is enhanced by the use of audio or video recordings. Computer digital recording of an interview allows faster access to playback portions of the interview for reliability study. The digital recordings are a resource for developing education and training materials, helping to improve standardisation of the SCAN internationally.