In this paper I shall discuss certain problems which arise in the theory of diagnosis and argue that there is a case for applying historical methods, as distinguished from scientific methods, as a possible approach towards solving them; and attempt also to show that such an approach may have value for generating research as well as being of practical use in clinical work.

In an earlier paper (Maxwell, 1972) the difficulties met in a dimensional approach to the description of symptomatology were discussed. In that study a representative sample of patients was considered under the three broad diagnostic categories, neurotics, affective psychotics and schizophrenics, and it was seen that all had a basic core of symptoms of the type generally referred to as ‘neurotic’, which lent themselves fairly well to a dimensional description and which indeed accounted for the greater part of the covariability of the symptoms in all three categories. But in addition the schizophrenics, and to some extent the affective psychotics, showed further symptoms of the type generally referred to as ‘psychotic’, though these occurred in a patchy and less general way than did the ‘neurotic’ symptoms. As a consequence these symptoms were not amenable to a dimensional description, nor did they lead to clear-cut typologies, as Everitt, Gourlay and Kendell (1971) have already shown.

From beginnings in imaginative literature and philosophy, the study of abnormal personality was taken up by clinicians who founded their investigations on the methods of observation and intuition. On the basis of case notes, experience and recollection, the pioneering psychiatrists constructed descriptive classifications which served as an initial taxonomy and enabled diagnostic and therapeutic work to proceed.

Psychiatrists differentiate types of abnormal personality in practice by assigning a descriptive label to indicate the chief way in which the patient's behaviour deviates from what is usual in society. The use by psychiatrists of such a category system for diagnosing abnormal personality has been discussed in two previous papers (Walton et al., 1970; Walton and Presly, 1973). The diagnostic system evaluated was one which included categories contained in the American Psychiatric Association classification (1968) and in the relevant section of the International Classification of Diseases (1965).

In 1957, Lewis, writing about obsessional neurotic illness, stated: ‘There has been no marked increase in our state of knowledge of it in recent years, and indeed much of what can be found on the subject in current textbooks had already been fully stated and closely discussed in the first two decades of this century ….’ A recurrent theme in the literature is the supposed relationship between obsessional neurotic illness and ‘obsessional’ character traits. The psychoanalytic view that there is a strong association between obsessional symptoms and the ‘anal’ character traits was disputed by Lewis (1935). He found little evidence to support the existence of a well-marked constellation of character traits, or of a relationship between ‘obsessional’ traits and obsessional neurotic illness. Sandler and Hazari (1960) gave supportive evidence for the psychoanalytic view, but Reed (1970) doubted whether their conclusions were justified by the findings. Makhlouf-Norris (1968) summarized the literature in fourteen points, two of which are outlined below.

When a frequency distribution of motor vehicle accidents in any particular group is analysed, there is found to be a number of individuals who have a greater proportion of accidents than can be explained by chance alone. Research on the psychology of accident causation has been aimed largely at isolating particular personality characteristics which seem to be associated with high accident liability. However, the results from past research have been far from encouraging. Very little has been conclusively proved regarding the bearing of any one attribute on the accident rate, and there is still no single specific factor that is psychometrically capable of being identified as a predictor of accident liability.

The incidence of tattooing is known to be high in certain selected groups.

The psychiatric out-patient department fulfils a comprehensive role in the diagnosis and treatment of a wide range of psychiatric disorders; it is no longer an annexe of the mental hospital principally concerned with providing follow-up and support for discharged patients. But despite the enormous growth of out-patient facilities and treatments, there have been few studies analysing the out-patient services. The Bethlem Royal and Maudsley Hospitals present detailed accounts of their out-patients, but although they serve a defined area their special functions possibly make their clientele unrepresentative. Diagnoses of out-patients in Buckinghamshire were analysed by Kessel and Shepherd (1962), but this survey gives no information about the treatment or disposal of patients. Innes and Sharp (1962) presented detailed statistics for combined inpatient and out-patients in the North East of Scotland, but did not separate the two classes of patients. The most comprehensive information concerning patients attending a hospital psychiatric out-patient department—their diagnosis, treatment and disposal—comes from Kessel and Hassall (1965 and 1971) in their evaluation of the functioning of the new Plymouth Nuffield Clinic, and from Kaeser and Cooper (1971) who investigated a group of general practitioner referrals to the Maudsley Hospital to assess the satisfaction gained by the patients and family doctors from such consultations.

Nowadays the idea of a day hospital is familiar and no longer seems revolutionary or slightly suspect. Considerable growth of such units has occurred since the Marlborough Day Hospital opened in London in 1946. However, there has been no real attempt in this country to accept the challenge of Epps and Hanes (1964) who estimated that 50–75 per cent of patients in psychiatric hospitals could be cared for equally well in day units.

Many patients in hospitals for the mentally subnormal are very isolated from the community (Ballinger, 1970). McKeown and Leck (1967) suggested that many individuals in these hospitals do not require hospital care and there have been recommendations that hospitals for the subnormal should be smaller in the future (Department of Health and Social Security, 1971).

In recent years provision of care for psychiatrically disturbed adolescents has received increasing attention. The present situation was summarized in a leading article in the British Medical Journal (1971) which emphasized one aspect of this provision—the need for adolescent in-patient facilities based within the community. This paper describes the ideas and practices of an adolescent unit which was opened at Hill End Hospital, St. Albans, in September 1969 to take younger adolescents (up to 16) of both sexes, from the area of the North-West Metropolitan Regional Hospital Board. This area covers 13,000 square miles and has a population of 4½ million, which the Unit aims to serve with 11 available beds. Who should be admitted to these places is clearly a critical question.

There is much neuropathological evidence that Alzheimer's Disease and senile dementia are essentially identical disorders (Stam, 1962; McMenemey, 1963; Jamada and Mehraein, 1968; Lauter, 1970; Torvik, 1970). Family and genetic studies also give support to this opinion, for there appears to be a tendency for both senile dementia and Alzheimer's Disease towards familial aggregation (Zerbin-Rüdin, 1967; Pratt, 1970). An extensive Swedish study has given evidence that senile dementia is determined by a single autosomal dominent gene (Sjögren et al., 1952). The difference in concordance rates between identical and non-identical twins with senile dementia is in agreement with this hypothesis (Kallmann, 1956). Furthermore, a number of families in which Alzheimer's Disease is transmitted as a regularly dominant trait have been described (Pratt, 1970). For the sporadic cases of Alzheimer's disease a cumulative polygenic action has been assumed (Larsson et al., 1963). Chromosome analysis of patients with Alzheimer's Disease and senile dementia has revealed certain abnormalities (Nielsen, 1968; Bergener and Jungklaass, 1970). Wheelan (1959) found that the MNSs blood groups appear to segregate with Alzheimer's Disease: however, another investigation failed to confirm a significant linkage between blood group genes and Alzheimer's Disease (Feldman, 1969).

Several previous studies have demonstrated involvement of the central nervous system in diabetes mellitus. Reske-Nielsen and Lundbaek (1963) gave a description of cerebral changes seen in an autopsy study of three cases of long term diabetes and considered these to contribute a diabetic encephalopathy. Lawrence et al. (1942) demonstrated lesions in the brain following fatal hypoglycaemia, and Fineberg and Altschul (1952) described cases in which permanent brain damage followed non-fatal hypoglycaemia. Grunnet (1963) found cerebral atherosclerosis to develop at an earlier age and more severely in the diabetic than the non-diabetic, and a higher incidence of cerebrovascular accident was found in diabetic than non-diabetic subjects by Alex et al. (1962).

The effect of emotional stress in myasthenia gravis is well known, and moreover Meyer (7) has shown that psychiatric problems make a considerable contribution to the mortality of the disease. It has been estimated that there are at least 1,100 diagnosed myasthenics in England and Wales with many more undiagnosed (5). Considering the close medical supervision myasthenics receive it is striking that in 677 cases of myasthenia subjected to psychiatric scrutiny only 2 schizophrenia-like reactions were observed, despite the similar age of onset of the two conditions.