In a recent series of investigations significant but conflicting relationships have been claimed between the two personality dimensions extraversion (E) and neuroticism (N) and certain spontaneous and induced features of the normal EEG. Savage (1964), using alpha abundance data from automatic frequency analysis, demonstrated a significant positive correlation between extraversion and high alpha amplitude. Extraversion has been similarly related to the amplitude of the averaged evoked potential waveform (Shagass and Schwartz, 1965). However, in an investigation by Broadhurst and Glass (1969) both alpha amplitude and prevalence bore an inverse relationship to E scores; extraversion was significantly associated with the rate of change of potential of the EEG, as was neuroticism with the alpha frequency. More recently, Winter et al. (1971) could find no direct relationship between extraversion and EEG amplitude, though there was a tendency for low amplitude activity to be associated with high neuroticism scores. The findings were interpreted as showing a significant interaction between the variables measured, the relationship of extraversion and amplitude varying according to the neuroticism score.

Eye-contact is a prominent Non-verbal cue in any Dyadic interaction and can be easily observed and measured. Argyle (1969) has postulated a relationship with Intimacy and Distance, Kendon (1967) described its expressive and regulatory function in conversation and Exline et al. (1965 and 1967) have related it to other variables, e.g. sex, dependency and affiliative needs.

Pain in organic disease has anatomical, physiological and psychological components which are inseparably linked, but there does not appear to be a strict relationship between the nature and apparent severity of noxious stimulation and the point at which different individuals experience pain. Moreover, in any group of patients at the same stage of an illness known to be associated with pain, some complain whereas others do not. Many factors are known to influence pain and complaint behaviour. The elderly experience less pain than younger patients with similar disorders (Exton-Smith, 1961). Pain thresholds tend to be lower in women than men, and racial differences are significant when considering both thresholds and complaint behaviour (Merskey and Spear, 1967). Pain may not be immediately associated with wounding in the physical and emotional struggles of battle, and the later intensity of suffering has been shown to be related to the significance of the wound to the patient (Beecher, 1956). There is an increase in pain in the presence of anxiety (Kennard, 1952; Masson, 1966) and Cole (1965) reported that factors associated with persistent pain include a disagreeable environment, a long history of pain, anxiety, depression, poor general health, resentment and lack of confidence in the doctor. Complaint behaviour is regarded by some as a learned response developed in childhood (Schilder, 1935; Russell, 1962; Sarbin, 1962; Simpson and others 1965). Bond and Pilowsky (1966) have demonstrated that in a clinical setting differences in complaint behaviour between the sexes depend in part upon the attitudes of nursing staff towards pain.

The diagnostic index is a most valuable tool when using a hospital's records for research purposes. This paper describes an attempt to produce such an index suitable for use in a busy psychiatric hospital. It was felt that priority should be given to simplicity and ease of use, as otherwise few of those concerned would have been able to spare the time needed for its preparation. Later an attempt was made to assess its reliability in use at two hospitals.