There is convincing evidence of a modest association between DUP and outcome, which supports the case for clinical trials that examine the effect of reducing DUP.

BackgroundWe conducted a systematic review of incidence rates in England over a sixty-year period to determine the extent to which rates varied along accepted (age, sex) and less-accepted epidemiological gradients (ethnicity, migration and place of birth and upbringing, time).ObjectivesTo determine variation in incidence of several psychotic disorders as above.Data SourcesPublished and grey literature searches (MEDLINE, PSycINFO, EMBASE, CINAHL, ASSIA, HMIC), and identification of unpublished data through bibliographic searches and author communication.Study Eligibility CriteriaPublished 1950–2009; conducted wholly or partially in England; original data on incidence of non-organic adult-onset psychosis or one or more factor(s) pertaining to incidence.ParticipantsPeople, 16–64 years, with first -onset psychosis, including non-affective psychoses, schizophrenia, bipolar disorder, psychotic depression and substance-induced psychosis.Study Appraisal and Synthesis MethodsTitle, abstract and full-text review by two independent raters to identify suitable citations. Data were extracted to a standardized extraction form. Descriptive appraisals of variation in rates, including tables and forest plots, and where suitable, random-effects meta-analyses and meta-regressions to test specific hypotheses; rate heterogeneity was assessed by the I2-statistic.Results83 citations met inclusion. Pooled incidence of all psychoses (N = 9) was 31.7 per 100,000 person-years (95%CI: 24.6–40.9), 23.2 (95%CI: 18.3–29.5) for non-affective psychoses (N = 8), 15.2 (95%CI: 11.9–19.5) for schizophrenia (N = 15) and 12.4 (95%CI: 9.0–17.1) for affective psychoses (N = 7). This masked rate heterogeneity (I2: 0.54–0.97), possibly explained by socio-environmental factors; our review confirmed (via meta-regression) the typical age-sex interaction in psychosis risk, including secondary peak onset in women after 45 years. Rates of most disorders were elevated in several ethnic minority groups compared with the white (British) population. For example, for schizophrenia: black Caribbean (pooled RR: 5.6; 95%CI: 3.4–9.2; N = 5), black African (pooled RR: 4.7; 95%CI: 3.3–6.8; N = 5) and South Asian groups in England (pooled RR: 2.4; 95%CI: 1.3–4.5; N = 3). We found no evidence to support an overall change in the incidence of psychotic disorder over time, though diagnostic shifts (away from schizophrenia) were reported.LimitationsIncidence studies were predominantly cross-sectional, limiting causal inference. Heterogeneity, while evidencing important variation, suggested pooled estimates require interpretation alongside our descriptive systematic results.Conclusions and Implications of Key FindingsIncidence of psychotic disorders varied markedly by age, sex, place and migration status/ethnicity. Stable incidence over time, together with a robust socio-environmental epidemiology, provides a platform for developing prediction models for health service planning.

Objective To describe long term outcomes associated with externalising behaviour in adolescence, defined in this study as conduct problems reported by a teacher, in a population based sample.Design Longitudinal study from age 13-53.Setting The Medical Research Council National Survey of Health and Development (the British 1946 birth cohort).Participants 3652 survey members assessed by their teachers for symptoms of externalising behaviour at age 13 and 15. Main outcome measures Mental disorder, alcohol abuse, relationship difficulties, highest level of education, social class, unemployment, and financial difficulties at ages 36-53.Results 348 adolescents were identified with severe externalising behaviour, 1051 with mild externalising behaviour, and 2253 with no externalising behaviour. All negative outcomes measured in adulthood were more common in those with severe or mild externalising behaviour in adolescence, as rated by teachers, compared with those with no externalising behaviour. Adolescents with severe externalising behaviour were more likely to leave school without any qualifications (65.2%; adjusted odds ratio 4.0, 95% confidence interval 2.9 to 5.5), as were those with mild externalising behaviour (52.2%; 2.3, 1.9 to 2.8), compared with those with no externalising behaviour (30.8%). On a composite measure of global adversity throughout adulthood that included mental health, family life and relationships, and educational and economic problems, those with severe externalising behaviour scored significantly higher (40.1% in top quarter), as did those with mild externalising behaviour (28.3%), compared with those with no externalising behaviour (17.0%).Conclusions Adolescents who exhibit externalising behaviour experience multiple social and health impairments that adversely affect them, their families, and society throughout adult life.

Background-Studies of the long-term course and outcome of psychoses tend to focus on cohorts of prevalent cases. Such studies bias samples toward those with poor outcomes, which may distort our understanding of prognosis. Long-term follow-up studies of epidemiologically robust first-episode samples are rare.

Item response theory (IRT) and categorical data factor analysis (CDFA) are complementary methods for the analysis of the psychometric properties of psychiatric measures that purport to measure latent constructs. These methods have been applied to relatively few child and adolescent measures. We provide the first combined IRT and CDFA analysis of a clinical measure (the Short Mood and Feelings Questionnaire-SMFQ) in a community sample of 7-through 11-year-old children. Both latent variable models supported the internal construct validity of a single underlying continuum of severity of depressive symptoms. SMFQ items discriminated well at the more severe end of the depressive latent trait. Item performance was not affected by age, although age correlated significantly with latent SMFQ scores suggesting that symptom severity increased within the age period of 7-11. These results extend existing psychometric studies of the SMFQ and confirm its scaling properties as a potential dimensional measure of symptom severity of childhood depression in community samples. KEY WORDS:Screening; childhood depression; SMFQ; item response theory; categorical data factor analysis.Over the last 40 years, the methods used to evaluate the psychometric basis of ability tests, health care surveys, and multi-item screening instruments has changed dramatically. Whilst the methodology of classical test theory (CTT) has served test development well, item response/latent trait theory (IRT) approaches have become more mainstream as the technical basis for measurement theory, test construction and scale evaluation (Embretson & Reise, 2000). Although moves towards adoption of more appropriate, non-linear and categorical data factor analysis (CDFA) models have been most apparent in ed- Costello, 2002;Cooke & Michie, 1997;Lambert et al., 2003;Patton, Carlin, Shao, Hibbert, & Bowes, 1997;Santor, Ramsay, & Zuroff, 1994). Currently there are very few reports that have applied such methodologies in samples of young children (Cheong & Raudenbush, 2000). One reason for the under-exploitation of such methodologies may be because researchers have not been introduced to the potential and practicalities of these methods (Rouse, Finger, & Butcher, 1999) and are therefore unaware of the advantages they offer over conventional (CTT) methods (van der Linden & Hambleton, 1997). Although CTT is often included in the curriculum of both clinical and applied psychologists, IRT is rarely taught, and has had less coverage in mainstream 380Sharp, Goodyer, and Croudace psychology journals (Embretson & Reise, 2000). We provide an application of IRT and categorical data factor analysis (CDFA) methods to a commonly used self-report measure of depressive symptoms in children, the Short Mood and Feelings Questionnaire (SMFQ; Angold et al., 1995). As such, the aim of this paper was to scrutinize the internal construct validity of the SMFQ. To this end, we used latent variable models implemented with both an IRT and appropriate factor analysis framework (CDFA). Within a lat...