There is growing concern that a substantial proportion of scientific research may in fact be false. A number of factors have been proposed as contributing to the presence of a large number of false-positive results in the literature, one of which is publication bias. We discuss empirical evidence for these factors.

A recent study by Morgan and colleagues found that cannabidiol attenuates the acute cognitive effects of delta-9-tetrahydrocannabinol (THC). This is of interest as THC has been associated with the detrimental effects of cannabis on mental health in at-risk users, and the potency of cannabis is increasing across Europe.

Law 180 eliminated psychiatric hospitals for the care of people with chronic psychosis in Italy. After 30 years, we review the consequences for the practice of psychiatry in Italy and parallels for England and Wales. We argue that the substitution of legal/political direction for clinical leadership means psychiatrists may cease to merit the privileges and responsibilities of being doctors.

Two major approaches can be used for the up-coming revisions of DSM–V and ICD–10: an ‘iterative model’ in which incremental changes are made or a ‘paradigm shift model’ in which the existing approach is jettisoned in favour of a new nosological model. We explore each of these two approaches and conclude that although they both have strengths and limitations, our field is not currently ready for a paradigm shift.

Treatment with antipsychotics seems to increase the risk of developing diabetes but the association is poorly characterised in clinical practice.

To investigate and characterise the incidence of diabetes for people treated with antipsychotic medication in clinical practice.

The study used the linkage of registers of all prescribed antipsychotics, antidiabetics and diagnoses of diabetes in Denmark during a period from 1996 to 2005 and identified all people treated with antipsychotics in Denmark and a random sample of about 30% of the total Danish population.

In total, 345 937 patients who purchased antipsychotics and 1 426 488 unexposed individuals were included in the study. Among the total population, 50 379 individuals subsequently developed incident diabetes. Compared with unexposed individuals, treatment with first- (rate ratio, RR = 1.53, 95% CI 1.49–1.56) as well as second-generation (RR = 1.32, 95% CI 1.22–1.42) antipsychotics was associated with increased risk of subsequent incident diabetes. The rate of incident diabetes varied substantially between individual second-generation antipsychotic drugs (olanzapine, risperidone clozapine compared with unexposed individuals: low to moderate rate ratio between 1.17 and 1.57; ziprasidone and sertindol: two or more times increased rate ratio; amisulpride, quetiapine and aripiprazole: no significantly increased rate ratio). For both first- and second-generation antipsychotics, the incidence of diabetes increased with the number of prescriptions. Additionally, the incidence of diabetes increased with the number of combined antipsychotic drugs.

In clinical practice, treatment with first- and second-generation antipsychotics is associated with an increased risk of developing incident diabetes with large differences between individual drugs. The risk increases with the duration of treatment and with polypharmacy of antipsychotic drugs.

People with mental health problems are more likely to die prematurely than the general population but no study has examined this in individuals with diabetes.

To compare survival rates in people with diabetes with and without schizophrenia or bipolar disorder.

A total of 43 992 people with diabetes were drawn from the QRESEARCH database population of over 9 million patients. Survival rates during the study period, between 1 April 2000 and 1 April 2005, and hazard ratios for deaths associated with schizophrenia and bipolar disorder were adjusted by age and gender and additionally for socioeconomic status, obesity, smoking and use of statins.

Among the participants, we identified 257 people diagnosed with schizophrenia, 159 with bipolar disorder and 14 with both conditions. Although crude survival rates did not show significant differences between the groups during the study period, people with schizophrenia or bipolar disorder and diabetes, compared with those with diabetes alone, had a significantly increased risk of death after adjusting for age and gender, with hazard ratios for schizophrenia of 1.84 (95% CI 1.42–2.40) and for bipolar disorder of 1.51 (95% CI 1.10–2.07). After adjusting for the other factors, hazard ratios were 1.52 (95 CI 1.17–1.97) for schizophrenia and 1.47 (95% CI 1.07–2.02) for bipolar disorder.

People with schizophrenia or bipolar disorder in addition to diabetes have a relatively higher mortality rate. This suggests that diabetes either progresses more rapidly or is more poorly controlled in these individuals, or that they have higher levels of comorbidity and so are more likely to die of other causes.

Decline in social functioning occurs in individuals who later develop psychosis.

To investigate whether baseline differences in disability are present in those who do and those who do not make a transition to psychosis in a group clinically at high risk and whether disability is a risk factor for transition.

Prospective multicentre, naturalistic field study with an 18-month follow-up period on 245 help-seeking individuals clinically at high risk. Disability was assessed with the Disability Assessment Schedule of the World Health Organization (WHODAS–II).

At baseline, the transition group displayed significantly greater difficulties in making new friends (z =−3.40, P = 0.001), maintaining a friendship (z =−3.00, P = 0.003), dealing with people they do not know (z =−2.28, P = 0.023) and joining community activities (z =−2.0, P = 0.05) compared with the non-transition group. In Cox regression, difficulties in getting along with people significantly contributed to the prediction of transition to psychosis in our sample (β = 0.569, s.e. = 0.184, Wald = 9.548, P = 0.002, hazard ratio (HR) = 1.767, 95% CI 1.238–2.550).

Certain domains of social disability might contribute to the prediction of psychosis in a sample clinically at high risk.

The two main constituents of cannabis, cannabidiol and δ9-tetrahydrocannabinol (THC), have opposing effects both pharmacologically and behaviourally when administered in the laboratory. Street cannabis is known to contain varying levels of each cannabinoid.

To study how the varying levels of cannabidiol and THC have an impact on the acute effects of the drug in naturalistic settings.

Cannabis users (n = 134) were tested 7 days apart on measures of memory and psychotomimetic symptoms, once while they were drug free and once while acutely intoxicated by their own chosen smoked cannabis. Using an unprecedented methodology, a sample of cannabis (as well as saliva) was collected from each user and analysed for levels of cannabinoids. On the basis of highest and lowest cannabidiol content of cannabis, two groups of individuals were directly compared.

Groups did not differ in the THC content of the cannabis they smoked. Unlike the marked impairment in prose recall of individuals who smoked cannabis low in cannabidiol, participants smoking cannabis high in cannabidiol showed no memory impairment. Cannabidiol content did not affect psychotomimetic symptoms, which were elevated in both groups when intoxicated.

The antagonistic effects of cannabidiol at the CB1 receptor are probably responsible for its profile in smoked cannabis, attenuating the memory-impairing effects of THC. In terms of harm reduction, users should be made aware of the higher risk of memory impairment associated with smoking low-cannabidiol strains of cannabis like ‘skunk’ and encouraged to use strains containing higher levels of cannabidiol.

Low- and middle-income countries lack information on contextualised mental health interventions to aid resource allocation decisions regarding healthcare.

To undertake a cost-effectiveness analysis of treatments for depression contextualised to Chile.

Using data from studies in Chile, we developed a computer-based Markov cohort model of depression among Chilean women to evaluate the cost-effectiveness of usual care or improved stepped care.

The incremental cost-effectiveness ratio (ICER) of usual care was I$113 per quality-adjusted life-year (QALY) gained, versus no treatment, whereas stepped care had an ICER of I$468 per QALY versus usual care. This compared favourably with Chile's per-capita GDP. Results were most sensitive to variation in recurrent episode coverage, marginally sensitive to cost of treatment, and insensitive to changes in health-state utility of depression and rate of recurrence.

Our results suggest that treatments for depression in lowand middle-income countries may be more cost-effective than previously estimated.

Therapist-delivered online cognitive–behavioural therapy (CBT) has been found to be effective for depression in primary care.

To determine the cost-effectiveness of online CBT compared with usual care.

Economic evaluation at 8 months alongside a randomised controlled trial. Cost to the National Health Service (NHS), personal costs, and the value of lost productivity, each compared with outcomes based on the Beck Depression Inventory and quality-adjusted life-years (QALYs). Incremental analysis indicated the NHS cost per QALY gain.

Online CBT was more expensive than usual care, although the outcomes for the CBT group were better. Cost per QALY gain based on complete case data was £17 173, and £10 083 when missing data were imputed.

Online CBT delivered by a therapist in real time is likely to be cost-effective compared with usual care if society is willing to pay at least £20 000 per QALY; it could be a useful alternative to face-to-face CBT.

Many adolescents with mental health problems experience transition of care from child and adolescent mental health services (CAMHS) to adult mental health services (AMHS).

As part of the TRACK study we evaluated the process, outcomes and user and carer experience of transition from CAMHS to AMHS.

We identified a cohort of service users crossing the CAMHS/AMHS boundary over 1 year across six mental health trusts in England. We tracked their journey to determine predictors of optimal transition and conducted qualitative interviews with a subsample of users, their carers and clinicians on how transition was experienced.

Of 154 individuals who crossed the transition boundary in 1 year, 90 were actual referrals (i.e. they made a transition to AMHS), and 64 were potential referrals (i.e. were either not referred to AMHS or not accepted by AMHS). Individuals with a history of severe mental illness, being on medication or having been admitted were more likely to make a transition than those with neurodevelopmental disorders, emotional/neurotic disorders and emerging personality disorder. Optimal transition, defined as adequate transition planning, good information transfer across teams, joint working between teams and continuity of care following transition, was experienced by less than 5% of those who made a transition. Following transition, most service users stayed engaged with AMHS and reported improvement in their mental health.

For the vast majority of service users, transition from CAMHS to AMHS is poorly planned, poorly executed and poorly experienced. The transition process accentuates pre-existing barriers between CAMHS and AMHS.

Although male prisoners are five times more likely to die by suicide than men of a similar age in the general population, the contribution of psychiatric disorders is not known.

To investigate the association of psychiatric disorders with near-lethal suicide attempts in male prisoners.

A matched case–control study of 60 male prisoners who made near-lethal suicide attempts (cases) and 60 prisoners who had never carried out near-lethal suicide attempts in prison (controls) was conducted. Psychiatric disorders were identified with the Mini International Neuropsychiatric Interview (MINI), and information on sociodemographic characteristics and criminal history was gathered using a semi-structured interview.

Psychiatric disorders were present in all cases and 62% of controls. Most current psychiatric disorders were associated with near-lethal suicide attempts, including major depression (odds ratio (OR) = 42.0, 95% CI 5.8–305), psychosis (OR = 15.0, 95% CI 2.0–113), anxiety disorders (OR = 6.0, 95% CI 2.3–15.5) and drug misuse (OR = 2.9, 95% CI 1.3–6.4). Lifetime psychiatric disorders associated with near-lethal attempts included recurrent depression and psychoses. Although cases were more likely than controls to meet criteria for antisocial personality disorder, the difference was not statistically significant. Comorbidity was also significantly more common among cases than controls for both current and lifetime disorders.

In male prisoners, psychiatric disorders, especially depression, psychosis, anxiety and drug misuse, are associated with near-lethal suicide attempts, and hence probably with suicide.

Hanging is the most frequently used method of suicide in the UK and has high case fatality (>70%).

To explore factors influencing the decision to use hanging.

Semi-structured qualitative interviews with 12 men and 10 women who had survived a near-fatal suicide attempt. Eight respondents had attempted hanging. Data were analysed thematically and with constant comparison.

Hanging was adopted or contemplated for two main reasons: the anticipated nature of a death from hanging; and accessibility. Those favouring hanging anticipated a certain, rapid and painless death with little awareness of dying and believed it was a ‘clean’ method that would not damage the body or leave harrowing images for others. Materials for hanging were easily accessed and respondents considered it ‘simple’ to perform without the need for planning or technical knowledge. Hanging was thus seen as the ‘quickest’ and ‘easiest’ method with few barriers to completion and sometimes adopted despite not being a first choice. Respondents who rejected hanging recognised it could be slow, painful and ‘messy’, and thought technical knowledge was needed for implementation.

Prevention strategies should focus on countering perceptions of hanging as a clean, painless and rapid method that is easily implemented. However, care is needed in the delivery of such messages as some individuals could gain information that might facilitate fatal implementation. Detailed research needs to focus on developing and evaluating interventions that can manage this tension.

Psychotic symptoms may occur in 15–64% of individuals with post-traumatic stress disorder, suggesting that the syndrome could be subtyped in a similar fashion to mood disorders. In our study of 1800 psychiatric out-patients who completed comprehensive diagnostic interviews, the lifetime prevalence of psychotic symptoms in people with PTSD was 17% (odds ratio (OR) = 3.48, 95% CI 2.32–5.21). However, after excluding people with comorbid conditions also known to be associated with psychotic symptoms this dropped to only 2.5% (OR) = 0.60, 95% CI 0.08–4.52). In contrast, rates of psychotic major depression did not change after excluding these same comorbidities. Our results do not support the official psychotic subtyping of PTSD.

The psychosocial effects of terrorist threat and close protection have never been studied systematically in political leaders. We conducted a study among 12 Dutch politicians and their partners who were living under terrorist threat and close protection in the aftermath of two political murders. Interviews revealed that their coping with the situation varied and consisted of emotion-focused, defensive, palliative and instrumental coping strategies. Symptoms of post-traumatic stress disorder occurred in some individuals, and tendencies to express milder or stronger opinions on sensitive issues were reported. Psychosocial knowledge can be useful in helping to cope with the situation in the best possible way.