People with serious mental illness are increasingly turning to popular social media, including Facebook, Twitter or YouTube, to share their illness experiences or seek advice from others with similar health conditions. This emerging form of unsolicited communication among self-forming online communities of patients and individuals with diverse health concerns is referred to as peer-to-peer support. We offer a perspective on how online peer-to-peer connections among people with serious mental illness could advance efforts to promote mental and physical wellbeing in this group.

In this commentary, we take the perspective that when an individual with serious mental illness decides to connect with similar others online it represents a critical point in their illness experience. We propose a conceptual model to illustrate how online peer-to-peer connections may afford opportunities for individuals with serious mental illness to challenge stigma, increase consumer activation and access online interventions for mental and physical wellbeing.

People with serious mental illness report benefits from interacting with peers online from greater social connectedness, feelings of group belonging and by sharing personal stories and strategies for coping with day-to-day challenges of living with a mental illness. Within online communities, individuals with serious mental illness could challenge stigma through personal empowerment and providing hope. By learning from peers online, these individuals may gain insight about important health care decisions, which could promote mental health care seeking behaviours. These individuals could also access interventions for mental and physical wellbeing delivered through social media that could incorporate mutual support between peers, help promote treatment engagement and reach a wider demographic. Unforeseen risks may include exposure to misleading information, facing hostile or derogatory comments from others, or feeling more uncertain about one's health condition. However, given the evidence to date, the benefits of online peer-to-peer support appear to outweigh the potential risks.

Future research must explore these opportunities to support and empower people with serious mental illness through online peer networks while carefully considering potential risks that may arise from online peer-to-peer interactions. Efforts will also need to address methodological challenges in the form of evaluating interventions delivered through social media and collecting objective mental and physical health outcome measures online. A key challenge will be to determine whether skills learned from peers in online networks translate into tangible and meaningful improvements in recovery, employment, or mental and physical wellbeing in the offline world.

To examine cross-national patterns and correlates of lifetime and 12-month comorbid DSM-IV anxiety disorders among people with lifetime and 12-month DSM-IV major depressive disorder (MDD).

Nationally or regionally representative epidemiological interviews were administered to 74 045 adults in 27 surveys across 24 countries in the WHO World Mental Health (WMH) Surveys. DSM-IV MDD, a wide range of comorbid DSM-IV anxiety disorders, and a number of correlates were assessed with the WHO Composite International Diagnostic Interview (CIDI).

45.7% of respondents with lifetime MDD (32.0–46.5% inter-quartile range (IQR) across surveys) had one of more lifetime anxiety disorders. A slightly higher proportion of respondents with 12-month MDD had lifetime anxiety disorders (51.7%, 37.8–54.0% IQR) and only slightly lower proportions of respondents with 12-month MDD had 12-month anxiety disorders (41.6%, 29.9–47.2% IQR). Two-thirds (68%) of respondents with lifetime comorbid anxiety disorders and MDD reported an earlier age-of-onset (AOO) of their first anxiety disorder than their MDD, while 13.5% reported an earlier AOO of MDD and the remaining 18.5% reported the same AOO of both disorders. Women and previously married people had consistently elevated rates of lifetime and 12-month MDD as well as comorbid anxiety disorders. Consistently higher proportions of respondents with 12-month anxious than non-anxious MDD reported severe role impairment (64.4 v. 46.0%; χ21 = 187.0, p < 0.001) and suicide ideation (19.5 v. 8.9%; χ21 = 71.6, p < 0.001). Significantly more respondents with 12-month anxious than non-anxious MDD received treatment for their depression in the 12 months before interview, but this difference was more pronounced in high-income countries (68.8 v. 45.4%; χ21 = 108.8, p < 0.001) than low/middle-income countries (30.3 v. 20.6%; χ21 = 11.7, p < 0.001).

Patterns and correlates of comorbid DSM-IV anxiety disorders among people with DSM-IV MDD are similar across WMH countries. The narrow IQR of the proportion of respondents with temporally prior AOO of anxiety disorders than comorbid MDD (69.6–74.7%) is especially noteworthy. However, the fact that these proportions are not higher among respondents with 12-month than lifetime comorbidity means that temporal priority between lifetime anxiety disorders and MDD is not related to MDD persistence among people with anxious MDD. This, in turn, raises complex questions about the relative importance of temporally primary anxiety disorders as risk markers v. causal risk factors for subsequent MDD onset and persistence, including the possibility that anxiety disorders might primarily be risk markers for MDD onset and causal risk factors for MDD persistence.

In this review, we provide an update of recent studies on the age of onset (AOO) of the major mental disorders, with a special focus on the availability and use of services providing prevention and early intervention.

The studies reviewed here confirm previous reports on the AOO of the major mental disorders. Although the behaviour disorders and specific anxiety disorders emerge during childhood, most of the high-prevalence disorders (mood, anxiety and substance use) emerge during adolescence and early adulthood, as do the psychotic disorders. Early AOO has been shown to be associated with a longer duration of untreated illness, and poorer clinical and functional outcomes.

Although the onset of most mental disorders usually occurs during the first three decades of life, effective treatment is typically not initiated until a number of years later. There is increasing evidence that intervention during the early stages of disorder may help reduce the severity and/or the persistence of the initial or primary disorder, and prevent secondary disorders. However, additional research is needed on effective interventions in early-stage cases, as well as on the long-term effects of early intervention, and for an appropriate service design for those with emerging mental disorders. This will mean not only the strengthening and re-engineering of existing systems, but is also crucial the construction of new streams of care for young people in transition to adulthood.

This paper is based on a report commissioned by the United Nations High Commissioner for Refugees, which aims to provide information on cultural aspects of mental health and psychosocial wellbeing relevant to care and support for Syrians affected by the crisis. This paper aims to inform mental health and psychosocial support (MHPSS) staff of the mental health and psychosocial wellbeing issues facing Syrians who are internally displaced and Syrian refugees.

We conducted a systematic literature search designed to capture clinical, social science and general literature examining the mental health of the Syrian population. The main medical, psychological and social sciences databases (e.g. Medline, PubMed, PsycInfo) were searched (until July 2015) in Arabic, English and French language sources. This search was supplemented with web-based searches in Arabic, English and French media, and in assessment reports and evaluations, by nongovernmental organisations, intergovernmental organisations and agencies of the United Nations. This search strategy should not be taken as a comprehensive review of all issues related to MHPSS of Syrians as some unpublished reports and evaluations were not reviewed.

Conflict affected Syrians may experience a wide range of mental health problems including (1) exacerbations of pre-existing mental disorders; (2) new problems caused by conflict related violence, displacement and multiple losses; as well as (3) issues related to adaptation to the post-emergency context, for example living conditions in the countries of refuge. Some populations are particularly vulnerable such as men and women survivors of sexual or gender based violence, children who have experienced violence and exploitation and Syrians who are lesbian, gay, bisexual, transgender or intersex. Several factors influence access to MHPSS services including language barriers, stigma associated with seeking mental health care and the power dynamics of the helping relationship. Trust and collaboration can be maximised by ensuring a culturally safe environment, respectful of diversity and based on mutual respect, in which the perspectives of clients and their families can be carefully explored.

Sociocultural knowledge and cultural competency can improve the design and delivery of interventions to promote mental health and psychosocial wellbeing of Syrians affected by armed conflict and displacement, both within Syria and in countries hosting refugees from Syria.

The standardised mean difference (SMD) is one of the most used effect sizes to indicate the effects of treatments. It indicates the difference between a treatment and comparison group after treatment has ended, in terms of standard deviations. Some meta-analyses, including several highly cited and influential ones, use the pre-post SMD, indicating the difference between baseline and post-test within one (treatment group).

In this paper, we argue that these pre-post SMDs should be avoided in meta-analyses and we describe the arguments why pre-post SMDs can result in biased outcomes.

One important reason why pre-post SMDs should be avoided is that the scores on baseline and post-test are not independent of each other. The value for the correlation should be used in the calculation of the SMD, while this value is typically not known. We used data from an ‘individual patient data’ meta-analysis of trials comparing cognitive behaviour therapy and anti-depressive medication, to show that this problem can lead to considerable errors in the estimation of the SMDs. Another even more important reason why pre-post SMDs should be avoided in meta-analyses is that they are influenced by natural processes and characteristics of the patients and settings, and these cannot be discerned from the effects of the intervention. Between-group SMDs are much better because they control for such variables and these variables only affect the between group SMD when they are related to the effects of the intervention.

We conclude that pre-post SMDs should be avoided in meta-analyses as using them probably results in biased outcomes.

Coronavirus disease 2019 (COVID-19) pandemic is a major public health concern all over the world. Little is known about the impact of COVID-19 pandemic on mental health in the general population. This study aimed to assess the mental health problems and associated factors among a large sample of college students during the COVID-19 outbreak in China.

This cross-sectional and nation-wide survey of college students was conducted in China from 3 to 10 February 2020. A self-administered questionnaire was used to assess psychosocial factors, COVID-19 epidemic related factors and mental health problems. Acute stress, depressive and anxiety symptoms were measured by the Chinese versions of the impact of event scale-6, Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7, respectively. Univariate and hierarchical logistic regression analyses were performed to examine factors associated with mental health problems.

Among 821 218 students who participated in the survey, 746 217 (90.9%) were included for the analysis. In total, 414 604 (55.6%) of the students were female. About 45% of the participants had mental health problems. The prevalence rates of probable acute stress, depressive and anxiety symptoms were 34.9%, 21.1% and 11.0%, respectively. COVID-19 epidemic factors that were associated with increased risk of mental health problems were having relatives or friends being infected (adjusted odds ratio = 1.72–2.33). Students with exposure to media coverage of the COVID-19 ≥3 h/day were 2.13 times more likely than students with media exposure <1 h/day to have acute stress symptoms. Individuals with low perceived social support were 4.84–5.98 times more likely than individuals with high perceived social support to have anxiety and depressive symptoms. In addition, senior year and prior mental health problems were also significantly associated with anxiety or/and depressive symptoms.

In this large-scale survey of college students in China, acute stress, anxiety and depressive symptoms are prevalent during the COVID-19 pandemic. Multiple epidemic and psychosocial factors, such as family members being infected, massive media exposure, low social support, senior year and prior mental health problems were associated with increased risk of mental health problems. Psychosocial support and mental health services should be provided to those students at risk.

Children and adolescents make up almost a quarter of the world's population with 85% living in low- and middle-income countries (LMICs). Globally, mental (and substance use) disorders are the leading cause of disability in young people; however, the representativeness or ‘coverage’ of the prevalence data is unknown. Coverage refers to the proportion of the target population (ages 5–17 years) represented by the available data.

Prevalence data for conduct disorder (CD), attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), eating disorders (EDs), depression, and anxiety disorders were sourced from systematic reviews conducted for the Global Burden of Disease Study 2010 (GBD 2010) and 2013 (GBD 2013). For each study, the location proportion was multiplied by the age proportion to give study coverage. Location proportion was calculated by dividing the total study location population by the total country population. Age proportion was calculated by dividing the population of the country aged within the age range of the study sample by the country population aged 5–17 years. If a study only sampled one sex, study coverage was halved. Coverage across studies was then summed for each country to give coverage by country. This method was repeated at the region and global level, and separately for GBD 2013 and GBD 2010.

Mean global coverage of prevalence data for mental disorders in ages 5–17 years was 6.7% (CD: 5.0%, ADHD: 5.5%, ASDs: 16.1%, EDs: 4.4%, depression: 6.2%, anxiety: 3.2%). Of 187 countries, 124 had no data for any disorder. Many LMICs were poorly represented in the available prevalence data, for example, no region in sub-Saharan Africa had more than 2% coverage for any disorder. While coverage increased between GBD 2010 and GBD 2013, this differed greatly between disorders and few new countries provided data.

The global coverage of prevalence data for mental disorders in children and adolescents is limited. Practical methodology must be developed and epidemiological surveys funded to provide representative prevalence estimates so as to inform appropriate resource allocation and support policies that address mental health needs of children and adolescents.

To update and expand on a 2012 systematic review of the prevalence and risk of violence and the prevalence and risk of physical, mental and sexual health problems among trafficked people.

Systematic review and meta-analysis. Searches of 15 electronic databases of peer-reviewed articles and doctoral theses were supplemented by reference screening, citation tracking of included articles and expert recommendations. Studies were included if they reported on the prevalence or risk of violence while trafficked, or the prevalence or risk of physical, mental or sexual health outcomes among people who have been trafficked. Two reviewers independently screened papers for eligibility and appraised the quality of included studies.

Thirty-seven papers reporting on 31 studies were identified. The majority of studies were conducted in low and middle-income countries with women and girls trafficked into the sex industry. There is limited but emerging evidence on the health of trafficked men and the health consequences of trafficking into different forms of exploitation. Studies indicate that trafficked women, men and children experience high levels of violence and report significant levels of physical health symptoms, including headaches, stomach pain and back pain. Most commonly reported mental health problems include depression, anxiety and post-traumatic stress disorder. Although serological data on sexually transmitted infections are limited, women and girls trafficked for sexual exploitation self-report symptoms suggestive of a high prevalence of infections. Limitations of the review include methodological weaknesses of primary studies and some differences in definition and operationalisation of trafficking, which hinder comparability and generalisability of the results.

There is increasing evidence human trafficking is associated with high prevalence and increased risk of violence and a range of physical and mental health problems. Although more studies have emerged in recent years reporting on the health of trafficked men and people trafficked for forms of exploitation other than in the sex industry, further research is needed in this area. Appropriate interventions and support services to address the multiple and serious medical needs, especially mental health, of trafficked people are urgently needed.

Mental health policy internationally varies in its support for recovery. The aims of this study were to validate an existing conceptual framework and then characterise by country the distribution, scientific foundations and emphasis in published recovery conceptualisations.

Update and modification of a previously published systematic review and narrative synthesis of recovery conceptualisations published in English.

A total of 7431 studies were identified and 429 full papers reviewed, from which 105 conceptualisations in 115 papers were included and quality assessed using established rating scales. Recovery conceptualisations were identified from 11 individual countries, with 95 (91%) published in English-speaking countries, primarily the USA (47%) and the UK (25%). The scientific foundation was primarily qualitative research (53%), non-systematic literature reviews (24%) and position papers (12%). The conceptual framework was validated with the 18 new papers. Across the different countries, there was a relatively similar distribution of codings for each of five key recovery processes.

Recovery as currently conceptualised in English-language publications is primarily based on qualitative studies and position papers from English-speaking countries. The conceptual framework was valid, but the development of recovery conceptualisations using a broader range of research designs within other cultures and non-majority populations is a research priority.

Although stigma in relation to mental health has been defined as including components of knowledge, attitudes and behaviour, no psychometrically tested instrument to assess behavioural discrimination at the population level has been developed. This paper presents details of the development and psychometric properties of the Reported and Intended Behaviour Scale (RIBS), an instrument based on the Star Social Distance Scale, to assess reported (past and current) and intended (future) behavioural discrimination among the general public against people with mental health problems.

Three studies were carried out to evaluate psychometric properties of the RIBS (Study 1, n = 92; Study 2, n = 37; Study 3, n = 403). Adults aged 25–45 in socio-economic groups: B, C1 and C2 (middle-income groups) took part in development and testing of the RIBS.

Internal consistency and test–retest reliability is moderate/substantial. Strong consensus validity was found, as rated by service users/consumers and international experts in stigma research.

Use of a behavioural outcome may be important to evaluate the effectiveness of interventions intended to reduce stigma and/or discrimination related to mental illness. The RIBS was found to be a brief, feasible and psychometrically robust measure for assessing mental health-related reported and intended behavioural discrimination.

There is strong evidence that those with a long-standing psychotic disorder have fewer social contacts and less social support than comparison groups. There is less research on the extent of social contacts and support prior to or at the onset of psychosis. In the light of recent evidence implicating a range of social experiences and contexts at the onset of psychosis, it is relevant to establish whether social networks and support diminished before or at the time of onset and whether the absence of such supports might contribute to risk, either directly or indirectly. We, therefore, conducted a systematic review of this literature to establish what is currently known about the relationship between social networks, support and early psychosis.

We identified all studies investigating social networks and support in first episode psychosis samples and in general population samples with measures of psychotic experiences or schizotype by conducting systematic searches of electronic databases using pre-defined search terms and criteria. Findings were synthesized using non-quantitative approaches.

Thirty-eight papers were identified that met inclusion criteria. There was marked methodological heterogeneity, which limits the capacity to draw direct comparisons. Nonetheless, the existing literature suggests social networks (particularly close friends) and support diminished both among first episode samples and among non-clinical samples reporting psychotic experiences or with schizotype traits, compared with varying comparison groups. These differences may be more marked for men and for those from minority ethnic populations.

Tentatively, reduced social networks and support appear to pre-date onset of psychotic disorder. However, the substantial methodological heterogeneity among the existing studies makes comparisons difficult and suggests a need for more robust and comparable studies on networks, support and early psychosis.

Anxiety disorders are widespread across the world. A systematic understanding of the disease burden, temporal trend and risk factors of anxiety disorders provides the essential foundation for targeted public policies on mental health at the national, regional, and global levels.

The estimation of anxiety disorders in the Global Burden of Disease Study 2019 using systematic review was conducted to describe incidence, prevalence and disability-adjusted life years (DALYs) in 204 countries and regions from 1990 to 2019. We calculated the estimated annual percentage change (EAPC) to quantify the temporal trends in anxiety disorders burden by sex, region and age over the past 30 years and analysed the impact of epidemiological and demographic changes on anxiety disorders.

Globally, 45.82 [95% uncertainty interval (UI): 37.14, 55.62] million incident cases of anxiety disorders, 301.39 million (95% UI: 252.63, 356.00) prevalent cases and 28.68 (95% UI: 19.86, 39.32) million DALYs were estimated in 2019. Although the overall age-standardised burden rate of anxiety disorders remained stable over the past three decades, the latest absolute number of anxiety disorders increased by 50% from 1990. We observed huge disparities in both age-standardised burden rate and changing trend of anxiety disorders in sex, country and age. In 2019, 7.07% of the global DALYs due to anxiety disorders were attributable to bullying victimisation, mainly among the population aged 5–39 years, and the proportion increased in almost all countries and territories compared with 1990.

Anxiety disorder is still the most common mental illness in the world and has a striking impact on the global burden of disease. Controlling potential risk factors, such as bullying, establishing effective mental health knowledge dissemination and diversifying intervention strategies adapted to specific characteristics will reduce the burden of anxiety disorders.

Major depressive disorders are highly prevalent in the world population, contribute substantially to the global disease burden and cause high health care expenditures. Information on the economic impact of depression, as provided by cost-of-illness (COI) studies, can support policymakers in the decision-making regarding resource allocation. Although the literature on COI studies of depression has already been reviewed, there is no quantitative estimation of depression excess costs across studies yet. Our aims were to systematically review COI studies of depression with comparison group worldwide and to assess the excess costs of depression in adolescents, adults, elderly, and depression as a comorbidity of a primary somatic disease quantitatively in a meta-analysis.

We followed the PRISMA reporting guidelines. PubMed, PsycINFO, NHS EED, and EconLit were searched without limitations until 27/04/2018. English or German full-text peer-reviewed articles that compared mean costs of depressed and non-depressed study participants from a bottom-up approach were included. We only included studies reporting costs for major depressive disorders. Data were pooled using a random-effects model and heterogeneity was assessed with I2 statistic. The primary outcome was ratio of means (RoM) of costs of depressed v. non-depressed study participants, interpretable as the percentage change in mean costs between the groups.

We screened 12 760 articles by title/abstract, assessed 393 articles in full-text and included 48 articles. The included studies encompassed in total 55 898 depressed and 674 414 non-depressed study participants. Meta-analysis showed that depression was associated with higher direct costs in adolescents (RoM = 2.79 [1.69–4.59], p < 0.0001, I2 = 87%), in adults (RoM = 2.58 [2.01–3.31], p < 0.0001, I2 = 99%), in elderly (RoM = 1.73 [1.47–2.03], p < 0.0001, I2 = 73%) and in participants with comorbid depression (RoM = 1.39 [1.24–1.55], p < 0.0001, I2 = 42%). In addition, we conducted meta-analyses for inpatient, outpatient, medication and emergency costs and a cost category including all other direct cost categories. Meta-analysis of indirect costs showed that depression was associated with higher costs in adults (RoM = 2.28 [1.75–2.98], p < 0.0001, I2 = 74%).

This work is the first to provide a meta-analysis in a global systematic review of COI studies for depression. Depression was associated with higher costs in all age groups and as comorbidity. Pooled RoM was highest in adolescence and decreased with age. In the subgroup with depression as a comorbidity of a primary somatic disease, pooled RoM was lower as compared to the age subgroups. More evidence in COI studies for depression in adolescence and for indirect costs would be desirable.