Background. A 10-question screening scale of psychological distress and a six-question short-form scale embedded within the 10-question scale were developed for the redesigned US National Health Interview Survey (NHIS).

Methods. Initial pilot questions were administered in a US national mail survey (N = 1401). A reduced set of questions was subsequently administered in a US national telephone survey (N = 1574). The 10-question and six-question scales, which we refer to as the K10 and K6, were constructed from the reduced set of questions based on Item Response Theory models. The scales were subsequently validated in a two-stage clinical reappraisal survey (N = 1000 telephone screening interviews in the first stage followed by N = 153 face-to-face clinical interviews in the second stage that oversampled first-stage respondents who screened positive for emotional problems) in a local convenience sample. The second-stage sample was administered the screening scales along with the Structured Clinical Interview for DSM-IV (SCID). The K6 was subsequently included in the 1997 (N = 36116) and 1998 (N = 32440) US National Health Interview Survey, while the K10 was included in the 1997 (N = 10641) Australian National Survey of Mental Health and Well-Being.

Results. Both the K10 and K6 have good precision in the 90th–99th percentile range of the population distribution (standard errors of standardized scores in the range 0·20–0·25) as well as consistent psychometric properties across major sociodemographic subsamples. The scales strongly discriminate between community cases and non-cases of DSM-IV/SCID disorders, with areas under the Receiver Operating Characteristic (ROC) curve of 0·87–0·88 for disorders having Global Assessment of Functioning (GAF) scores of 0–70 and 0·95–0·96 for disorders having GAF scores of 0–50.

Conclusions. The brevity, strong psychometric properties, and ability to discriminate DSM-IV cases from non-cases make the K10 and K6 attractive for use in general-purpose health surveys. The scales are already being used in annual government health surveys in the US and Canada as well as in the WHO World Mental Health Surveys. Routine inclusion of either the K10 or K6 in clinical studies would create an important, and heretofore missing, crosswalk between community and clinical epidemiology.

Background. The paper reports on the development of the WHOQOL-BREF, an abbreviated version of the WHOQOL-100 quality of life assessment.

Method. The WHOQOL-BREF was derived from data collected using the WHOQOL-100. It produces scores for four domains related to quality of life: physical health, psychological, social relationships and environment. It also includes one facet on overall quality of life and general health.

Results. Domain scores produced by the WHOQOL-BREF correlate highly (0·89 or above) with WHOQOL-100 domain scores (calculated on a four domain structure). WHOQOL-BREF domain scores demonstrated good discriminant validity, content validity, internal consistency and test–retest reliability.

Conclusion. These data suggest that the WHOQOL-BREF provides a valid and reliable alternative to the assessment of domain profiles using the WHOQOL-100. It is envisaged that the WHOQOL-BREF will be most useful in studies that require a brief assessment of quality of life, for example, in large epidemiological studies and clinical trials where quality of life is of interest. In addition, the WHOQOL-BREF may be of use to health professionals in the assessment and evaluation of treatment efficacy.

This is an introductory report for the Brief Symptom Inventory (BSI), a brief psychological self-report symptom scale. The BSI was developed from its longer parent instrument, the SCL-90-R, and psychometric evaluation reveals it to be an acceptable short alternative to the complete scale. Both test-retest and internal consistency reliabilities are shown to be very good for the primary symptom dimensions of the BSI, and its correlations with the comparable dimensions of the SCL-90-R are quite high. In terms of validation, high convergence between BSI scales and like dimensions of the MMPI provide good evidence of convergent validity, and factor analytic studies of the internal structure of the scale contribute evidence of construct validity. Several criterion-oriented validity studies have also been completed with this instrument

This study reports the factor structure of the symptoms comprising the General Health Questionnaire when it is completed in a primary care setting. A shorter, 28-item GHQ is proposed consisting of 4 subscales: somatic symptoms, anxiety and insomnia, social dysfunction and severe depression. Preliminary data concerning the validity of these scales are presented, and the performance of the whole 28-item questionnaire as a screening test is evaluated. The factor structure of the symptomatology is found to be very similar for 3 independent sets of data.

Psychometric and clinical correlates of the Eating Attitudes Test (EAT) are described for a large sample of female anorexia nervosa (N = 160) and female comparison (N = 140) subjects. An abbreviated 26-item version of the EAT (EAT-26) is proposed, based on a factor analysis of the original scale (EAT-40). The EAT-26 is highly correlated with the EAT-40 (r = 0·98) and three factors form subscales which are meaningfully related to bulimia, weight, body-image variables and psychological symptoms. Whereas there are no differces between bulimic and restricter anorexia nervosa patients on the total EAT-26 and EAT-40 scores, these groups do indicate significant differences on EAT-26 fractors. Norms for the anorexia nervosa and female comparison subjects are presented for the EAT-26, EAT-40 and the EAT-26 factors. It is concluded that the EAT-26 is a reliable, valid and economical instrument which may be useful as an objective measure of the symptoms of anorexia nervosa.

Background. In recent years the 12-item General Health Questionnaire (GHQ-12) has been extensively used as a short screening instrument, producing results that are comparable to longer versions of the GHQ.

Methods. The validity of the GHQ-12 was compared with the GHQ-28 in a World Health Organization study of psychological disorders in general health care. Results are presented for 5438 patients interviewed in 15 centres using the primary care version of the Composite International Diagnostic Instrument, or CIDI-PC.

Results. Results were uniformly good, with the average area under the ROC curve 88, range from 83 to 95. Minor variations in the criteria used for defining a case made little difference to the validity of the GHQ, and complex scoring methods offered no advantages over simpler ones. The GHQ was translated into 10 other languages for the purposes of this study, and validity coefficients were almost as high as in the original language. There was no tendency for the GHQ to work less efficiently in developing countries. Finally gender, age and educational level are shown to have no significant effect on the validity of the GHQ.

Conclusions. If investigators wish to use a screening instrument as a case detector, the shorter GHQ is remarkably robust and works as well as the longer instrument. The latter should only be preferred if there is an interest in the scaled scores provided in addition to the total score.

Data on the development of a 40-item measure of the symptoms in anorexia nervosa are reported. The scale (EAT) is presented in a 6-point, forced choice, self-report format which is easily administered and scored. The EAT was validated using 2 groups of female anorexia nervosa patients (N = 32 and 33) and female control subjects (N = 34 and 59). Total EAT score was significantly correlated with criterion group membership(r = 0·87, P < 0·001), suggesting a high level of concurrent validity. There was very little overlap in the frequency distributions of the 2 groups and only 7% of the normal controls scored as high as the lowest anorexic patient. Female obese and male subjects also scored significantly lower on the EAT than anorexics. Recovered anorexic patients scored in the normal range on the test, suggesting that the EAT is sensitive to clinical remission.

Background. A self-report screening scale of adult attention-deficit/hyperactivity disorder (ADHD), the World Health Organization (WHO) Adult ADHD Self-Report Scale (ASRS) was developed in conjunction with revision of the WHO Composite International Diagnostic Interview (CIDI). The current report presents data on concordance of the ASRS and of a short-form ASRS screener with blind clinical diagnoses in a community sample.

Method. The ASRS includes 18 questions about frequency of recent DSM-IV Criterion A symptoms of adult ADHD. The ASRS screener consists of six out of these 18 questions that were selected based on stepwise logistic regression to optimize concordance with the clinical classification. ASRS responses were compared to blind clinical ratings of DSM-IV adult ADHD in a sample of 154 respondents who previously participated in the US National Comorbidity Survey Replication (NCS-R), oversampling those who reported childhood ADHD and adult persistence.

Results. Each ASRS symptom measure was significantly related to the comparable clinical symptom rating, but varied substantially in concordance (Cohen's κ in the range 0·16–0·81). Optimal scoring to predict clinical syndrome classifications was to sum unweighted dichotomous responses across all 18 ASRS questions. However, because of the wide variation in symptom-level concordance, the unweighted six-question ASRS screener outperformed the unweighted 18-question ASRS in sensitivity (68·7% v. 56·3%), specificity (99·5% v. 98·3%), total classification accuracy (97·9% v. 96·2%), and κ (0·76 v. 0·58).

Conclusions. Clinical calibration in larger samples might show that a weighted version of the 18-question ASRS outperforms the six-question ASRS screener. Until that time, however, the unweighted screener should be preferred to the full ASRS, both in community surveys and in clinical outreach and case-finding initiatives.

Two previous epidemiological studies of autistic twins suggested that autism was predominantly genetically determined, although the findings with regard to a broader phenotype of cognitive, and possibly social, abnormalities were contradictory. Obstetric and perinatal hazards were also invoked as environmentally determined aetiological factors. The first British twin sample has been re-examined and a second total population sample of autistic twins recruited. In the combined sample 60% of monozygotic (MZ) pairs were concordant for autism versus no dizygotic (DZ) pairs; 92% of MZ pairs were concordant for a broader spectrum of related cognitive or social abnormalities versus 10% of DZ pairs. The findings indicate that autism is under a high degree of genetic control and suggest the involvement of multiple genetic loci. Obstetric hazards usually appear to be consequences of genetically influenced abnormal development, rather than independent aetiological factors. Few new cases had possible medical aetiologies, refuting claims that recognized disorders are common aetiological influences.

A systematic review of all reported incidence and prevalence studies of population rates of subclinical psychotic experiences reveals a median prevalence rate of around 5% and a median incidence rate of around 3%. A meta-analysis of risk factors reveals associations with developmental stage, child and adult social adversity, psychoactive drug use, and also male sex and migrant status. The small difference between prevalence and incidence rates, together with data from follow-up studies, indicates that approximately 75–90% of developmental psychotic experiences are transitory and disappear over time. There is evidence, however, that transitory developmental expression of psychosis (psychosis proneness) may become abnormally persistent (persistence) and subsequently clinically relevant (impairment), depending on the degree of environmental risk the person is additionally exposed to. The psychosis proneness–persistence–impairment model considers genetic background factors impacting on a broadly distributed and transitory population expression of psychosis during development, poor prognosis of which, in terms of persistence and clinical need, is predicted by environmental exposure interacting with genetic risk.

The psychometric properties of the 28- and 30-item versions of the Inventory of Depressive Symptomatology, Clinician-Rated (IDS-C) and Self-Report (IDS-SR) are reported in a total of 434 (28-item) and 337 (30-item) adult out-patients with current major depressive disorder and 118 adult euthymic subjects (15 remitted depressed and 103 normal controls). Cronbach's α ranged from 0·92 to 0·94 for the total sample and from 0·76 to 0·82 for those with current depression.

Item total correlations, as well as several tests of concurrent and discriminant validity are reported. Factor analysis revealed three dimensions (cognitive/mood, anxiety/arousal and vegetative) for each scale. Analysis of sensitivity to change in symptom severity in an open-label trial of fluoxetine (N = 58) showed that the IDS-C and IDS-SR were highly related to the 17-item Hamilton Rating Scale for Depression. Given the more complete item coverage, satisfactory psychometric properties, and high correlations with the above standard ratings, the 30-item IDS-C and IDS-SR can be used to evaluate depressive symptom severity. The availability of similar item content for clinician-rated and self-reported versions allows more direct evaluations of these two perspectives.

Background. This study examined the persistence of attention deficit hyperactivity disorder (ADHD) into adulthood.

Method. We analyzed data from published follow-up studies of ADHD. To be included in the analysis, these additional studies had to meet the following criteria: the study included a control group and it was clear from the methods if the diagnosis of ADHD included subjects who did not meet full criteria but showed residual and impairing signs of the disorder. We used a meta-analysis regression model to separately assess the syndromatic and symptomatic persistence of ADHD.

Results. When we define only those meeting full criteria for ADHD as having ‘persistent ADHD’, the rate of persistence is low, ~15% at age 25 years. But when we include cases consistent with DSM-IV's definition of ADHD in partial remission, the rate of persistence is much higher, ~65%.

Conclusions. Our results show that estimates of ADHD's persistence rely heavily on how one defines persistence. Yet, regardless of definition, our analyses show that evidence for ADHD lessens with age. More work is needed to determine if this reflects true remission of ADHD symptoms or is due to the developmental insensitivity of diagnostic criteria for the disorder.

Background. Research on the dimensional structure and reliability of the Hospital Anxiety and Depression Scale (HADS) and its relationship with age is scarce. Moreover, its efficacy in determining the presence of depression in different patient groups has been questioned.

Methods. Psychometric properties of the HADS were assessed in six different groups of Dutch subjects (N = 6165): (1) a random sample of younger adults (age 18–65 years) (N = 199); (2) a random sample of elderly subjects of 57 to 65 years of age (N = 1901); (3) a random sample of elderly subjects of 66 years or older (N = 3293); (4) a sample of consecutive general practice patients (N = 112); (5) a sample of consecutive general medical out-patients with unexplained somatic symptoms (N = 169); and (6) a sample of consecutive psychiatric out-patients (N = 491).

Results. Evidence for a two-factor solution corresponding to the original two subscales of the HADS was found, although anxiety and depression subscales were strongly correlated. Homogeneity and test–retest reliability of the total scale and the subscales were good. The dimensional structure and reliability of the HADS was stable across medical settings and age groups. The correlations between HADS scores and age were small. The total HADS scale showed a better balance between sensitivity and positive predictive value (PPV) in identifying cases of psychiatric disorder as defined by the Present State Examination than the depression subscale in identifying cases of unipolar depression as defined by ICD-8.

Conclusions. The moderate PPV suggests that the HADS is best used as a screening questionnaire and not as a ‘case-identifier’ for psychiatric disorder or depression.

Visual Analogue Scales (VAS) provide a simple technique for measuring subjective experience. They have been established as valid and reliable in a range of clinical and research applications, although there is also evidence of increased error and decreased sensitivity when used some subject groups. Decisions concerned with the choice of scoring interval, experimental design, and statistical analysis for VAS have in some instances been based on convention, assumption and convenience, highlighting the need for more comprehensive assessment of individual scales if this versatile and sensitive measurement technique is to be used to full advantage.

Background. The psychological autopsy method offers the most direct technique currently available for examining the relationship between particular antecedents and suicide. This systematic review aimed to examine the results of studies of suicide that used a psychological autopsy method.

Method. A computer aided search of MEDLINE, BIDS ISI and PSYCHLIT, supplemented by reports known to the reviewers and reports identified from the reference lists of other retrieved reports. Two investigators systematically and independently examined all reports. Median proportions were determined and population attributable fractions were calculated, where possible, in cases of suicide and controls.

Results. One hundred and fifty-four reports were identified, of which 76 met the criteria for inclusion; 54 were case series and 22 were case–control studies. The median proportion of cases with mental disorder was 91% (95% CI 81–98%) in the case series. In the case–control studies the figure was 90% (88–95%) in the cases and 27% (14–48%) in the controls. Co-morbid mental disorder and substance abuse also preceded suicide in more cases (38%, 19–57%) than controls (6%, 0–13%). The population attributable fraction for mental disorder ranged from 47–74% in the seven studies in which it could be calculated. The effects of particular disorders and sociological variables have been insufficiently studied to draw clear conclusions.

Conclusions. The results indicated that mental disorder was the most strongly associated variable of those that have been studied. Further studies should focus on specific disorders and psychosocial factors. Suicide prevention strategies may be most effective if focused on the treatment of mental disorders.

Thirty patients were selected for a prospective study according to two criteria: (i) an irresistible urge to overeat (bulimia nervosa), followed by self-induced vomiting or purging; (ii) a morbid fear of becoming fat. The majority of the patients had a previous history of true or cryptic anorexia nervosa. Self-induced vomiting and purging are secondary devices used by the patients to counteract the effects of overeating and prevent a gain in weight. These devices are dangerous for they are habit-forming and lead to potassium loss and other physical complications. In common with true anorexia nervosa, the patients were determined to keep their weight below a self-imposed threshold. Its level was set below the patient‘s healthy weight, defined as the weight reached before the onset of the eating disorder. In contrast with true anorexia nervosa, the patients tended to be heavier, more active sexually, and more likely to menstruate regularly and remain fertile. Depressive symptoms were often severe and distressing and led to a high risk of suicide.

A theoretical model is described to emphasize the interdependence of the various symptoms and the role of self-perpetuating mechanisms in the maintenance of the disorder. The main aims of treatment are (i) to interrupt the vicious circle of overeating and self-induced vomiting (or purging), (ii) to persuade the patients to accept a higher weight. Prognosis appears less favourable than in uncomplicated anorexia nervosa.

Background. Two new screening scales for psychological distress, the K6 and K10, have been developed but their relative efficiency has not been evaluated in comparison with existing scales.

Method. The Australian National Survey of Mental Health and Well-Being, a nationally representative household survey, administered the WHO Composite International Diagnostic Interview (CIDI) to assess 30-day DSM-IV disorders. The K6 and K10 were also administered along with the General Health Questionnaire (GHQ-12), the current de facto standard of mental health screening. Performance of the three screening scales in detecting CIDI/DSM-IV mood and anxiety disorders was assessed by calculating the areas under receiver operating characteristic curves (AUCs). Stratum-Specific Likelihood Ratios (SSLRs) were computed to help produce individual-level predicted probabilities of being a case from screening scale scores in other samples.

Results. The K10 was marginally better than the K6 in screening for CIDI/DSM-IV mood and anxiety disorders (K10 AUC: 0·90, 95%CI: 0·89–0·91 versus K6 AUC: 0·89, 95%CI: 0·88–0·90), while both were significantly better than the GHQ-12 (AUC: 0·80, 95%CI: 0·78–0·82). The SSLRs of the K10 and K6 were more informative in ruling in or out the target disorders than those of the GHQ-12 at both ends of the population spectrum. The K6 was more robust than the K10 to subsample variation.

Conclusions. While the K10 might outperform the K6 in screening for severe disorders, the K6 is preferred in screening for any DSM-IV mood or anxiety disorder because of its brevity and consistency across subsamples. Precision of individual-level prediction is greatly improved by using polychotomous rather than dichotomous classification.