For some phenomena the mean of population distributions predicts the proportion of people exceeding a threshold value.

To investigate whether in depression, too, the population mean predicts the number of individuals at the extreme end of the distribution.

We used data from the European Outcome in Depression International Network (ODIN) study from populations in Finland, Norway and the UK to create models that predicted the prevalence of depression based on the mean Beck Depression Inventory (BDI) score. The models were tested on data from Ireland and Spain.

Mean BDI score correlated well with the prevalence of depression determined by clinical interviews. A model based on the beta distribution best fitted the BDI distribution. Both models predicted the depression prevalence in Ireland and Spain fairly well.

The mean of a continuous population distribution of mood predicts the prevalence of depression. Characteristics of both individuals and populations determine depression rates.

There has been continued interest in the extent to which women have positive and negative reactions to abortion.

To document emotional reactions to abortion, and to examine the links between reactions to abortion and subsequent mental health outcomes.

Data were gathered on the pregnancy and mental health history of a birth cohort of over 500 women studied to the age of 30.

Abortion was associated with high rates of both positive and negative emotional reactions; however, nearly 90% of respondents believed that the abortion was the right decision. Analyses showed that the number of negative responses to the abortion was associated with increased levels of subsequent mental health disorders (P<0.05). Further analyses suggested that, after adjustment for confounding, those having an abortion and reporting negative reactions had rates of mental health disorders that were approximately 1.4–1.8 times higher than those not having an abortion.

Abortion was associated with both positive and negative emotional reactions. The extent of negative emotional reactions appeared to modify the links between abortion and subsequent mental health problems.

Studies examining the impact of childhood disaster exposure on the development of adult psychopathology report increased rates of post-traumatic stress disorder (PTSD) and other psychopathology.

To examine the rates of PTSD and other lifetime DSM–IV disorders in adults exposed to an Australian bushfire disaster as children in 1983 using a matched control sample recruited at the time of the original study.

A total of 1011 adults recruited from an original sample of 1531 were assessed 20 years following the fires using the Composite International Diagnostic Interview (CIDI–2.1).

Results showed only a small direct impact of the fires on adult psychiatric morbidity. A higher proportion of bushfire survivors met criteria for ‘any DSM–IV disorder’ and ‘any anxiety’.

Findings suggest that the long-term impact of a prominent trauma in childhood should be assessed in the context of other lifetime trauma in order to provide a more accurate account of PTSD prevalence rates.

There is a paucity of data describing how general practitioners (GPs) label or record depression.

To determine incidence and sociodemographic variation in GP-recorded depression diagnoses and depressive symptoms.

Annual incidence rates calculated using data from 298 UK general practices between 1996 and 2006, adjusted for year of diagnosis, gender, age and deprivation.

Incidence of diagnosed depression fell from 22.5 to 14.0 per 1000 person-years at risk (PYAR) from 1996 to 2006. The incidence of depressive symptoms rose threefold from 5.1 to 15.5 per 1000 PYAR. Combined incidence of diagnoses and symptoms remained stable. Diagnosed depression and symptoms were more common in women and in more deprived areas.

Depression recorded by general practitioners has lower incidence rates than depression recorded in epidemiological studies, although there are similar associations with gender and deprivation. General practitioners increasingly use symptoms rather than diagnostic labels to categorise people's illnesses. Studies using standardised diagnostic instruments may not be easily comparable with clinical practice.

There has been no reported research comparing Jewish Israeli and Palestinian adolescents regarding the effect of ongoing political violence on adolescent psychosocial, family, post-traumatic stress disorder (PTSD) and aggression problems.

To compare Israeli and Palestinian responses regarding the relationship between exposure to traumatic events and psychosocial, behavioural, emotional and family problems.

A cluster sample of youths aged 14–18 years, including 442 Jewish Israeli adolescents in Ariel, Haifa and Tel-Aviv, and 450 Palestinian adolescents in Gaza cities, villages and refugee camps were surveyed in 2006 using our Traumatic Events Questionnaire (TEV), the Brief Symptoms Inventory (BSI), the PTSD Symptom Scale – Interview (PSS–I), the Index of Peer Relations scale (IPR), Buss–Perry Aggression Questionnaire (BPAQ) and the MacMaster Family Assessment Device (FAD).

Palestinian respondents had higher scores in the TEV, BSI, PSS–I and BPAQ questionnaires, and greater problems in functioning as revealed in the IPR and FAD. The social functioning of the adolescents with their peers predicted mental health symptoms and PTSD symptoms. Lower socioeconomic status predicted mental health symptoms, PTSD, pathology of participants' family functioning and the social functioning of the adolescents with their peers. Parents' education positively effected the FAD score and the avoidance item on the PSS–I, and religiosity improved the score on the FAD. Females reported more symptoms on the BSI and PSS–I than males, and males more symptoms on the FAD and IPR than females.

Both respondent groups had significant emotional and behavioural problems. Individual and community treatment, and community and social development, are likely to be useful for both populations, particularly Palestinians.

Little is known about the cross-national population prevalence or correlates of personality disorders.

To estimate prevalence and correlates of DSM–IV personality disorder clusters in the World Health Organization World Mental Health (WMH) Surveys.

International Personality Disorder Examination (IPDE) screening questions in 13 countries (n = 21 162) were calibrated to masked IPDE clinical diagnoses. Prevalence and correlates were estimated using multiple imputation.

Prevalence estimates are 6.1% (s.e. = 0.3) for any personality disorder and 3.6% (s.e. = 0.3), 1.5% (s.e. = 0.1) and 2.7% (s.e. = 0.2) for Clusters A, B and C respectively. Personality disorders are significantly elevated among males, the previously married (Cluster C), unemployed (Cluster C), the young (Clusters A and B) and the poorly educated. Personality disorders are highly comorbid with Axis I disorders. Impairments associated with personality disorders are only partially explained by comorbidity.

Personality disorders are relatively common disorders that often co-occur with Axis I disorders and are associated with significant role impairments beyond those due to comorbidity.

No previous community-based epidemiological study has explored psychiatric disorders among those who survived the Holocaust.

To examine anxiety and depressive disorders, sleep disturbances, other health problems and use of services among individuals exposed and unexposed to the Holocaust.

The relevant population samples were part of the Israel World Mental Health Survey. The interview schedule included the Composite International Diagnostic Interview and other health-related items.

The Holocaust survivor group had higher lifetime (16.1%; OR = 6.8, 95% CI 1.9–24.2) and 12-month (6.9%; OR = 22.5, 95% CI 2.5–204.8) prevalence rates of anxiety disorders, and more current sleep disturbances (62.4%; OR = 2.5, 95% CI 1.4–4.4) and emotional distress (P<0.001) than their counterparts, but did not have higher rates of depressive disorders or post-traumatic stress disorder.

Early severe adversity was associated with psychopathological disorder long after the end of the Second World War, but not in all survivors. Age during the Holocaust did not modify the results.

Prospective data on the association between common mental disorders and obesity are scarce, and the impact of ageing on this association is poorly understood.

To examine the association between common mental disorders and obesity (body mass index 30 kg/m2) across the adult life course.

The participants, 6820 men and 3346 women, aged 35–55 were screened four times during a 19-year follow-up (the Whitehall II study). Each screening included measurements of mental disorders (the General Health Questionnaire), weight and height.

The excess risk of obesity in the presence of mental disorders increased with age (P = 0.004). The estimated proportion of people who were obese was 5.7% at age 40 both in the presence and absence of mental disorders, but the corresponding figures were 34.6% and 27.1% at age 70. The excess risk did not vary by gender or according to ethnic group or socioeconomic position.

The association between common mental disorders and obesity becomes stronger at older ages.

It has been suggested that rural–urban migration will have adverse consequences for older parents left behind.

To describe correlates of outmigration and to estimate any association between outmigration of children and depression in rural-dwelling older parents.

Population-based survey of 1147 parents aged 60 and over in rural Thailand. We randomly oversampled parents living without children. We defined an outmigrant child as living outside their parent's district, and measured depression as a continuous outcome with a Thai version of the EURO–D.

Outmigration of all children, compared with outmigration of some or no children, was independently associated with less depression in parents. This association remained after taking account of social support, parent characteristics, health and wealth. Parents with all children outmigrated received more economic remittances and they perceived support to be as good as that of those with children close by.

Outmigration of children was not associated with greater depression in older parents and, after taking account of a range of possible covariables, was actually associated with less parental depression. This could be explained by pre-existing advantages in families sending more migrants and by the economic benefits of migration.

Much remains unknown about the phenomenology of bipolar I disorder.

To determine the type of bipolar I mood episodes that occur over time, and their relative frequency.

A total of 219 individuals with Research Diagnostic Criteria bipolar I disorder were prospectively followed for up to 25 years (median 20 years). Psychopathology was assessed with the Longitudinal Interval Follow-up Evaluation.

Overall, 1208 mood episodes were prospectively observed. The episodes were empirically classified as follows: major depression, 30.9% (n = 373); minor depression, 13.0% (n = 157); mania, 20.4% (n = 246); hypomania, 10.4% (n = 126); cycling, 17.3% (n = 210); cycling plus mixed state, 7.8% (n = 94); and mixed, 0.2% (n = 2).

Cycling episodes constituted 25% of all episodes. Work groups revising ICD–10 and DSM–IV should add a category for bipolar I cycling episode.

Substance misuse is a common comorbid problem in people presenting with first-episode psychosis and is associated with a poor short-term outcome.

The aim of this study is to examine differences in baseline characteristics and 1-year outcome between individuals with first-episode psychosis who have never misused substances, those who stop misusing substances after initial presentation and those who persistently misuse substances over the 1-year assessment period.

Patients were recruited to the Northern Ireland First Episode Psychosis Study (n = 272). Clinical assessments were performed at baseline and at 1 year (n = 194) and data were collected from the case notes.

Individuals with persistent substance misuse had more severe depression, more positive symptoms, poorer functional outcome and greater rates of relapse at 1 year than those who stopped and those who had never misused substances. There were no differences in outcome between people who had never misused substances and those who stopped misusing after presentation.

These results support assertive intervention targeted at comorbid substance misuse in individuals with first-episode psychosis.

Identifying neurocognitive subtypes in schizophrenia may help establish neurobiologically meaningful subtypes of the disorder, but is frequently confounded by differences in intellectual function between individuals with schizophrenia and controls.

To examine neuropsychological performance in individuals with epidemiologically based, first-onset schizophrenia and intellectually matched controls.

Using standard IQ and reading tests, we examined the proportions of 101 people with epidemiologically derived, first-onset schizophrenia/schizoaffective disorder and 317 community controls, falling into three a priori defined intellectual categories: ‘stable good’, ‘deteriorated poor’ and ‘stable poor’. Neuropsychological function was compared between intellectually matched participants with schizophrenia and control subgroups.

Multiple deficits in executive function, processing speed and verbal memory, but not visual/spatial perception/memory, were detected in all participant groups with schizophrenia compared with controls. The average effect size across the affected domains ranged from small to medium to large in the stable good, deteriorated poor and stable poor subgroups of participants with schizophrenia, respectively.

Compared with intellectually matched controls, people with epidemiologically derived, first-onset schizophrenia/schizoaffective disorder show multiple deficits in executive function, processing speed and verbal memory.

There is little evidence of the feasibility, acceptability and impact of services for the care of people with psychotic disorders in low- and middle-income countries.

To describe the scaling up and impact of a community-based rehabilitation programme for people with psychotic disorders in a very-low-resource setting.

Longitudinal study of people with psychotic disorders who had been ill for an average of 8 years in a rural Indian community. All individuals received a community-based intervention package comprising psychotropic medications, psychoeducation, adherence management, psychosocial rehabilitation and support for livelihoods. The primary outcome was change in disability scores.

The cohort consisted of 256 people with psychotic disorders (schizophrenia, bipolar affective disorder and other psychosis) of whom 236 people completed the end-point assessments (92%), with a median follow-up of 46 months. There were significant reductions (P<0.05) in the levels of disability for the cohort, the vast majority (83.5%) of whom engaged with the programme. On multivariate analyses, lower baseline disability scores, family engagement with the programme, medication adherence and being a member of a self-help group were independent determinants of good outcomes. Lack of formal education, a diagnosis of schizophrenia and dropping out of the programme were independent determinants of poor outcomes.

Community-based rehabilitation is a feasible and acceptable intervention with a beneficial impact on disability for the majority of people with psychotic disorders in low-resource settings. The impact on disability is influenced by a combination of clinical, programme and social determinants.

The mechanism underlying the association between urban birth/upbringing and increased schizophrenia risk is unknown. This study explored whether an urban effect might be present in a low-income country setting, where the ‘urban’ environment may have radically different components, for example urban architecture, pollution levels or social cohesion.

To investigate the potential association of urbanicity of place of birth and symptoms of psychosis, depression and anxiety in Uganda.

Ugandans aged 18–30 years (n = 646) were interviewed using the Peters et al Delusions Inventory (PDI–21), the Hopkins Symptoms Checklist (HSCL–25) and psychoticism items from the Symptoms Checklist 90-items version (SCL–90) in Mbarara and Kampala districts and asked about their birthplace.

Urban birth (but not semi-urban) was associated with more lifetime psychotic experiences, especially grandiosity, and more symptoms of psychosis, depression and anxiety during the past week.

The urban risk factor for schizophrenia may be universally present across different levels of human development, albeit the nature of the mechanism remains elusive.

Increasing numbers of people will die with dementia, many in the acute hospital. It is often not perceived to be a life-limiting illness.

To investigate the prevalence of dementia in older people undergoing emergency medical admission and its effect on outcomes.

Longitudinal cohort study of 617 people (aged over 70). The main outcome was mortality risk during admission.

Of the cohort, 42.4% had dementia (only half diagnosed prior to admission). In men aged 70–79, dementia prevalence was 16.4%, rising to 48.8% of those over 90. In women, 29.6% aged 70–79 had dementia, rising to 75.0% aged over 90. Urinary tract infection or pneumonia was the principal cause of admission in 41.3% of the people with dementia. These individuals had markedly higher mortality; 24.0% of those with severe cognitive impairment died during admission (adjusted mortality risk 4.02, 95% CI 2.24–7.36).

The rising prevalence of dementia will have an impact on acute hospitals. Extra resources will be required for intermediate and palliative care and mental health liaison services.

Internet-delivered self-help programmes with added therapist guidance have shown efficacy in social anxiety disorder, but unguided self-help has been insufficiently studied.

To evaluate the efficacy of guided and unguided self-help for social anxiety disorder.

Participants followed a cognitive–behavioural self-help programme in the form of either pure bibliotherapy or an internet-based treatment with therapist guidance and online group discussions. A subsequent trial was conducted to evaluate treatment specificity. Participants (n = 235) were randomised to one of three conditions in the first trial, or one of four conditions in the second.

Pure bibliotherapy and the internet-based treatment were better than waiting list on measures of social anxiety, general anxiety, depression and quality of life. The internet-based therapy had the highest effect sizes, but directly comparable effects were noted for bibliotherapy augmented with online group discussions. Gains were well maintained a year later.

Unguided self-help through bibliotherapy can produce enduring improvement for individuals with social anxiety disorder.

The pattern of brain morphological changes at the early stages of schizophrenia may depend on the age at onset of illness; in children and adolescents with schizophrenia, grey matter deficits are seen in the parietal lobe whereas in individuals with adult onset these are more widespread.

To examine whether white matter is similarly affected.

Diffusion tensor imaging was used to compare fractional anisotropy measures in individuals with adolescent-onset (n = 17) and adult-onset schizophrenia (n = 17) with those in age- and gender-matched controls.

Compared with their respective controls, individuals with adolescent-onset schizophrenia showed fractional anisotropy decrease in parietal regions; individuals with adult onset showed additional fractional anisotropy reductions in frontal, temporal and cerebellar regions. A differential effect of age at onset (adolescent v. adult) was noted bilaterally in medial prefrontal white matter.

White matter abnormalities in frontal regions in schizophrenia may depend on developmental stage at the time of illness onset.