Researchers agree that suicides are under-reported, although estimates of the extent vary. Dublin (1963) suggested that recorded figures were understated by one fourth to one third. Seager and Flood (1965) estimated that possible suicides among deaths reported as accidents, misadventure or open verdicts might be as many as 50 per cent of those actually returned as suicide. Important sources of under-reporting lie in the methods of ascertaining and recording suicide as well as in religious and social attitudes, which tend, in certain countries, to look upon suicide as a stigma and to avoid a verdict of suicide where possible.

People who kill themselves are grouped together as suicides on the basis of that one action, yet they can hardly be considered to be a homogenous class. Attempts to define sub-categories among suicides can be made in a number of different ways, none by itself entirely satisfactory. Differentiation by psychiatric diagnosis is one possibility, but is difficult to achieve and throws little light on the undoubted contribution of social factors. Sociological studies have usually persisted in regarding all suicides as intrinsically similar, and have sought to relate variations in rates between different sections of the community in terms of general social variables such as status integration, social isolation, anomie and the like. Yet suicides are not a uniform group, and relatively little can be achieved while this fact is ignored.

Until a few years ago, suicides and attempted suicides were regarded as a homogeneous group. Stengel, Cook, and Kreeger (1958) pointed out that they are two different but overlapping populations. The 'overlap' has been demonstrated by follow-up studies of attempted suicide which reveal only a small proportion who later committed suicide (0*3 % to 22% depending upon the duration of follow-up), and by retrospective studies on completed suicides showing that only a small proportion of these had made previous attempts (8 6 % to 333 % in any unselected and consecutive series of suicides) (Dorpat and Ripley, 1967). Investigation of the full spectrum of suicidal behaviour requires the integration of detailed data on both suicides and attempted suicides occurring in the same population over the same period of time. The majority of researchers have studied the two patterns of behaviour in different populations or in different areas or at different times with ensuing problems of interpretation. Those few studies making a contemporaneous comparison have been restricted by difficulties in representative sampling among the attempted suicide population (Schmid and Van Arsdol, 1955, in Seattle; Farberow and Schneidman, 1961, in Los Angeles; Stengel et al., 1958, in London; Ropschitz and Ovenstone, 1968, in Halifax). This occurred either because the studies were carried out at a time when suicidal behaviour was a legal offence, as in London and Seattle, and precautions would be taken to conceal all but the most serious attempts, or the data were based on hospitalized cases and therefore likely to be biased towards persons requiring admission. The Los Angeles study did, however, include cases notified to them by the community physicians (from whom they had a 70 % response) and achieved what they called 'a fair but undoubtably conservative figure' for attempted suicides occurring over their research period. Sampling presents less difficulty in Edinburgh as 98 % of all suicidal attempts sent to, or presenting at, hospitals in the area are admitted to the Regional Poisoning Treatment Centre (RPTC) no matter how trivial the attempt. It has been demonstrated that 80 % of the cases seen in general practice are also admitted and that the RPTC population is representative of those attempting suicide in Edinburgh (Kennedy, 1971).In most studies data relating to completed suicides have been obtained from coroners' records, which it is accepted under-report the problem.

The aim of this paper is to describe and compare the prevalence patterns of completed suicide and so-called ‘attempted suicide’ or parasuicide, as they occur in a single, defined population over the same period of time.

No abstract