An evidenced-based approach to psychiatry is playing an increasingly prominent role in treatment decision-making for individual patients and for populations. Many doctors are now critical of the emphasis being placed on ‘the evidence’ and concerned that clinical practice will become more constrained.

To demonstrate that evidence-based medicine is not new, sources of evidence are limited and psychosocial aspects of medicine are neglected in this process.

Some of the literature is reviewed. Ideas and arguments are synthesised into a critical commentary.

These are considered under four headings: evidence-based medicine is not new; what evidence is acceptable; the doctor as therapist; and the emergence of a new utilitarian orthodoxy.

It is agreed that a degree of professional consensus is necessary. However, too great an emphasis on evidence-based medicine oversimplifies the complex and interpersonal nature of clinical care.

Psychiatric therapy needs assessment regarding its maturation as a therapeutic science.

Judgement of whether such a science is emerging.

Four criteria are used: efficacy; identification of responsible treatment components; knowledge of their mechanisms of action; and elucidation of why they act only in some sufferers.

Brief behavioural, interpersonal, cognitive, problem-solving and other psychotherapies have a mature ability to improve anxiety and depressive disorders reliably and enduringly, often only with instruction from a manual or a computer. Therapy's cost-effectiveness and acceptability deserve more attention. We know little about which treatment components produce improvement, how they do so and why they do not help all sufferers.

Therapy is coming of age regarding efficacy for anxiety and depression, but is only a toddler regarding the scientific principles to explain its effects.

There is an ethical imperative to evaluate service and policy initiatives, such as those highlighted in the recent National Service Framework, just as there is to evaluate individual treatments.

To outline the best methods available for evaluating the delivery and organisation of mental health services.

We present a narrative methodological overview, using salient examples from mental health services research.

Cluster randomised studies involve the random allocation of groups of clinicians, clinical teams or hospitals rather than individual patients, and produce the least biased evaluation of mental health policy, organisation or service delivery. Where randomisation is impossible or impractical (often when services or policies are already implemented), then quasi-experimental designs can be used. Such designs have both strengths and many potential flaws.

The gold standard remains the randomised trial, but with due consideration to the unit of randomisation. Use of quasi-experimental designs can be justified in certain circumstances but should be attempted and interpreted with caution.

Proposals by the UK Government for preventive detention of people with ‘dangerous severe personality disorders' highlight the unresolved issue of whether personality disorders should be regarded as mental illnesses.

To clarify the issue by examining the concepts of psychopathy and personality disorder, the attitudes of contemporary British psychiatrists to personality disorders, and the meaning of the terms ‘mental illness'and ‘mental disorder’.

The literature on personality disorder is assessed in the context of four contrasting concepts of illness or disease.

Whichever of the four concepts or definitions is chosen, it is impossible to conclude with confidence that personality disorders are, or are not, mental illnesses; there are ambiguities in the definitions and basic information about personality disorders is lacking.

The historical reasons for regarding personality disorders as fundamentally different from mental illnesses are being undermined by both clinical and genetic evidence. Effective treatments for personality disorders would probably have a decisive influence on psychiatrists' attitudes.

For more than 20 years, the Impact of Event Scale (IES) has been widely used as a measure of stress reactions after traumatic events.

To review studies that evaluated the IES's psychometric properties.

Literature review.

The results indicated that the IES's two-factor structure is stable over different types of events, that it can discriminate between stress reactions at different times after the event, and that it has convergent validity with observer-diagnosed post-traumatic stress disorder. The use of IES in many psychopharmacological trials and outcome studies is supportive of the measure's clinical relevance.

The IES is a useful measure of stress reactions after a range of traumatic events, and it is valuable for detecting individuals who require treatment.

When parenteral treatments are indicated for acutely disturbed behaviour, previous guidelines have recommended droperidol or haloperidol in combination with benzodiazepines. However, there has been recent concern over cardiotoxicity and sudden death associated with some antipsychotic medication and droperidol has now been withdrawn.

To ascertain what alternatives can be recommended to replace intramuscular droperidol.

Selective review of current guidelines and the literature pertaining to rapid parenteral tranquillisation.

Current guidelines recommend haloperidol as an alternative to droperidol. There is evidence of cardiotoxicity with haloperidol and it has a propensity to cause extrapyramidal side effects that may exacerbate disturbed behaviour and reduce longer-term compliance. The rapid-acting intramuscular formulations of atypical antipsychotic agents show promise.

It is recommended that the mainstay of pharmacological rapid tranquillisation should be parenteral benzodiazepines used with due care.

Women who are positive for thyroid antibodies in early gestation are prone to post-partum depression, apparently independent of thyroid dysfunction, as measured by serum levels of free thyroxine, free triodothyroxine and thyroid-stimulating hormone. This finding may be due to infrequent monitoring of thyroid function, because hyperthyroidism, hypothyroidism and combinations of both may occur post-partum.

To test the hypothesis that stabilising thyroid function post-partum by administering daily thyroxine reduces the rate of occurrence and severity of associated depression.

In a randomised double-blind placebo-controlled trial, 100 of thyroxine or placebo was given daily to 446 thyroid-antibody-positive women (342 of whom were compliant) from 6 weeks to 6 month spost-partum, assessing their psychiatric and thyroid status at 4-weeklyintervals.

There was no evidence that thyroxine had any effect on the occurrence of depression. The 6-month period prevalence of depression was similar to that reported previously.

The excess of depression in thyroid-antibody-positive women in the post-partum period is not corrected by daily administration of thyroxine.

The high risk for dementia in adults with Down's syndrome has been attributed to triplication and overexpression of the gene for amyloid precursor protein (APP). But the wide variation in age at onset must be due to other risk factors.

To identify factors which influence age at onset of dementia in Down's syndrome.

Studies of factors which influence formation of beta-amyloid (Aβ) were reviewed, including atypical karyotypes, susceptibility genotypes, gender and oestrogen deficiency, and individual differences in Aβ peptide levels.

The apolipoprotein E $4 allele, oestrogen deficiency and high levels of Aβl-42 peptide are associated with earlier onset of dementia, while atypical karyotypes and the apolipoprotein E $2 allele are associated with reduced mortality and reduced risk of dementia.

Factors which influence Aβ levels, rather than overexpression of APP, may account for the differences in age at onset of dementia in Down's syndrome.

Claims that schizophrenia is a disease of the limbic system have been strengthened by meta-analyses of magnetic resonance imaging (MRI) studies finding reduced hippocampus and amygdala volumes. Some post-mortem studies do not find these abnormalities.

To assess the volume of the amygdala in a series of brains post-mortem.

Amygdala volume was estimated using point-counting in both hemispheres of the brains of 10 male and 8 female patients with schizophrenia, and a comparison group of 9 males and 9 females.

No significant reduction of amygdala volume was found.

Significant volume reduction of the amygdala is not a consistent feature of schizophrenia; findings from early MRI studies using coarse delineation methods may introduce bias to subsequent meta-analyses.

Old age psychiatry is no less subject to increasing legal and quasi-legal restraint than other branches of the profession, but the emphases are different. Two themes predominate: first, that of capacity or competence; and second, to what extent formal legal measures should be implemented in cases where incapacitated patients do not dissent from, as opposed to giving active consent to, admission to hospital or receiving treatment.

To discuss the issues of capacity or competence, especially in relation to recent legislation and judgements and to proposed legislation in England and Wales.

Selective review and discussion of recent case law and current and proposed statute law.

The Bournewood case threatened but ultimately failed to upset the status quo. However, the European Convention on Human Rights and the British Human Rights Act 1998 may yet do so.

It is now accepted that people with schizophrenia are significantly more likely to be violent than other members of the general population. A less acknowledged fact is that the proportion of societal violence attributable to schizophrenia is small.

To critically examine the epidemiological evidence for the association between violence and schizophrenia and estimate the impact of this association on society.

A selective review of the key literature on the epidemiology of violence and schizophrenia. Population-attributable risks for violence in schizophrenia are calculated from population-based studies.

Most studies confirm the association between violence and schizophrenia. Recent good evidence supports a small but independent association. Comorbid substance abuse considerably increases this risk. The proportion of violent crime in society attributable to schizophrenia consistently falls below 10%.

Less focus on the relative risk and more on the absolute risk of violence posed to society by people with schizophrenia would serve to reduce the associated stigma. Strategies aimed at reducing this small risk require further attention, in particular treatment for substance misuse.

Australia commenced a 5-year reform of mental health services in 1993.

To report on the changes to mental health services achieved by 1998.

Analysis of data from the Australian National Mental Health Report 2000 and an independent evaluation of the National Mental Health Strategy.

Mental health expenditure increased 30% in real terms, with an 87% growth in community expenditures, a 38% increase in general hospitals and a 29% decrease in psychiatric hospitals. The growth in private psychiatry, averaging 6% annually prior to 1992, was reversed. Consumer and carer involvement in services increased.

Major structural reform was achieved but there was limited evidence that these changes had been accompanied by improved service quality. The National Mental Health Strategy was renewed for another 5 years.

Depression in childhood or adolescence often has morbidity implications continuing into adulthood, generating needs for specialist services and support.

To estimate the patterns of service use and costs in adulthood of former patients.

Service use and other cost-related data were collected from former patients. Comparisons were made between those people with and without comorbid conduct disorder in childhood and with data for the general population.

Data on 91 people with depression (only) and 49 with comorbid conduct disorder revealed high adulthood service utilisation rates and costs. Inpatient care and criminal justice services were used more frequently by the comorbid group and total costs were significantly higher. There were also indications of higher service use by the comorbid group than the general adult population.

The high and enduring long-term costs associated with childhood depression and conduct disorder give further reason for early and effective intervention.

Depression is common in later life.

To determine whether exercise is effective as an adjunct to antidepressant therapy in reducing depressive symptoms in older people.

Patients were randomised to attend either exercise classes or health education talks for 10 weeks. Assessments were made ‘blind’ at baseline, and at 10 and 34 weeks. The primary outcome was seen with the 17-item Hamilton Rating Scale for Depression (HRSD). Secondary outcomes were seen with the Geriatric Depression Scale, Clinical Global Impression and Patient Global Impression.

At 10 weeks a significantly higher proportion of the exercise group (55% v. 33%) experienced a greater than 30% decline in depression according to HRSD (OR=2.51, P=0.05, 95% Cl 1.00–6.38).

Because exercise was associated with a modest improvement in depressive symptoms at 10 weeks, older people with poorly responsive depressive disorder should be encouraged to attend group exercise activities.

It is not clear how far brain abnormalities in early-onset schizophrenia result from progressive neurodevelopmental or neurodegenerative processes.

To investigate the hypothesis that structural brain abnormalities in adolescent-onset schizophrenia are progressive in the early phase of the illness.

A magnetic resonance imaging case–control study of 16 adolescents with schizophrenia (mean age 16.6 years, s.d.=1.9 years) with a meantime of 2.7 years (s.d.=1.7 years) between measurements and 16 matched controls (average age 16.0 years, s. d.=2.0 years) with a mean time of 1.7 years (s.d.=0.5 years) between measurements.

There was no evidence of progressive structural brain changes during late adolescence. Significant ventricular enlargement (greater in males) and left-sided temporal lobe changes were evident from the outset of the illness.

Neurodevelopmental brain abnormalities are non-progressive during late adolescence.

Individuals with schizophrenia appear to be at increased risk for violent and criminal behaviour. Obstetric complications, neuromotor problems and intellectual deficits have variously been reported as increasing the risk for criminality in the general population.

To investigate whether such risk factors are associated with criminal behaviour in an epidemiological cohort of patients with schizophrenia.

We identified from health care registers all individuals with schizophrenia born in Helsinki between 1951 and 1960, and used the national criminal register to identify those with a criminal record by 1995. Childhood information was obtained from archived birth and school records.

Poor educational attainment, poor grades for attention at school, higher birth weight and larger head circumference were significantly associated with the risk of criminal offending in adulthood in this sample of patients with schizophrenia. An association between labour/delivery complications and later violent offending among male patients was of borderline significance.

Our hypotheses that birth complications and childhood neuromotor problems would increase the risk of criminal offending in schizophrenia were not upheld.

Neuroendocrine studies of brain serotonin (5-HT) function in depression generally show evidence of impaired 5-HT function but it is disputed whether or not this impairment resolves with clinical recovery.

To use the endocrine response to the selective 5-HTreuptake inhibitor, citalopram, to study brain 5-HT function in acute and recovered depressed subjects relative to healthy controls.

We used a double-blind, placebo-controlled design to measure the prolactin and cortisol responses to citalopram (10 mg intravenously) in patients with major depression, in unmedicated subjects recovered from depression and in healthy controls.

The prolactin responses to citalopram were blunted similarly in both acutely depressed and recovered subjects. The cortisol responses were blunted in the acutely depressed patients but not in the recovered subjects.

Our data support the proposal that some aspects of impaired 5-HT neurotransmission may be trait markers of vulnerability to depression. The recovery of the cortisol response to citalopram may indicate resolution of hypothalamic – pituitary-adrenal axis dysfunction.

There is concern in the community about increasing cannabis use and its potential effect on health.

To ascertain the prevalence of cannabis use among Australian adolescents, associations with mental health problems, risk behaviours and service use.

Examination of data from a national representative sample of households comprising 1261 adolescents aged 13–17 years. Parents completed a psychiatric interview and questionnaires while adolescents completed questionnaires.

One-quarter of the adolescents in the sample had used cannabis. There were no gender differences. Use increased rapidly with age, was more common in adolescents living with a sole parent and was associated with increased depression, conduct problems and health risk behaviours (smoking, drinking) but not with higher use of services.

Cannabis use is very prevalent. The association with depression, conduct problems, excessive drinking and use of other drugs shows a malignant pattern of comorbidity that may lead to negative outcomes.

Psychotherapy research rarely has studied outcome in the longer term.

To evaluate the effectiveness of brief group dynamic psychotherapy (BGDP) intervention in patients with minor psychiatric disorders compared with the usual clinical management shortly after treatment termination and to investigate whether intervention would show a differential effect at 2-year follow-up.

Patients were allocated randomly to an experimental or control group. The General Health Questionnaire (GHQ) was used as a primary outcome measure.

Based on improvement in the GHQ, at termination of treatment the BGDP group showed a significant improvement in 23 out of 42 (54.8%) compared with II out of 41 (26.8%) in the clinical management group. The difference in the total improvement rate is 28% (95% Cl 8–48) (χ2=67; d.f.=l; P=0.009). In contrast, no differential follow-up effects were found between the BGDP and clinical management groups.

Psychotherapy appears to have beneficial effects at termination of treatment but the changes attained were not stable.

The high support needs of elderly people with cognitive disability raise questions about the cost-effectiveness of different treatments. Associations between costs and cognitive disability could be influenced by other factors, particularly comorbidities.

To examine the links between costs and cognitive disability in the context of covariates.

Secondary analyses of data from the UK Office of Population Censuses and Surveys disability surveys for over 4500 elderly people living in households were used to examine associations between cost and cognitive disability.

Costs varied considerably, and were associated with severity of disability along a number of dimensions. The cost-raising effects of cognitive disability were smaller when the analyses controlled for levels of disability in other domains.

Cognitive disability is significantly associated with higher costs, but these analyses highlight the need to examine a range of disabilities.