Background. Psychosocial interventions for bipolar patients often include teaching patients to recognize prodromal symptoms and tackle them early. This prospective study set out to investigate which bipolar prodromal symptoms were reported frequently and reliably over a period of 18 months. Furthermore, we have also investigated which types of coping strategies were related to good outcome.

Method. Forty bipolar patients were interviewed for their bipolar prodromal symptoms and their coping strategies at recruitment and 18 months later. Patients were also assessed as to whether they had experienced relapses.

Results. Bipolar patients were able to report bipolar prodromal symptoms reliably. Mania prodromal symptoms tended to be behavioural symptoms. A quarter of patients reported difficulties in detecting depression prodromes, which tended to be more diverse and consisted of a mix of behavioural, cognitive and somatic symptoms. Significantly fewer patients who reported the use of behavioural coping strategies to curb excessive behaviour during the mania prodromal stage experienced a manic episode. Similarly, significantly fewer patients who reported the use of behavioural coping strategies experienced depression relapses. How well patients coped with mania prodromes predicted bipolar episodes significantly when the mood levels at baseline were controlled. Ratings of how well subjects coped with mania prodromal symptoms also predicted manic symptoms significantly at T2 when manic symptom at T1 was controlled.

Conclusion. Our study suggests that bipolar patients are able to report prodromal symptoms reliably. It is advisable to teach patients to monitor their moods systematically and to promote good coping strategies.

Background. We used functional MRI to examine the functional anatomy of inner speech and different forms of auditory verbal imagery (imagining speech) in normal volunteers. We hypothesized that generating inner speech and auditory verbal imagery would be associated with left inferior frontal activation, and that generating auditory verbal imagery would involve additional activation in the lateral temporal cortices.

Methods. Subjects were scanned, while performing inner speech and auditory verbal imagery tasks, using a 1.5 Tesla magnet.

Results. The generation of inner speech was associated with activation in the left inferior frontal/insula region, the left temporo-parietal cortex, right cerebellum and the supplementary motor area. Auditory verbal imagery in general, as indexed by the three imagery tasks combined, was associated with activation in the areas engaged during the inner speech task, plus the left precentral and superior temporal gyri (STG), and the right homologues of all these areas.

Conclusions. These results are consistent with the use of the ‘articulatory loop' during both inner speech and auditory verbal imagery, and the greater engagement of verbal self-monitoring during auditory verbal imagery.

Background. Depressive syndromes not fulfilling the criteria for specified disorders (subthreshold depression, SD) may be clinically important. We aimed to study SD in old and very old age, in comparison with subjects with no depressive symptoms (NDS) and subjects with major depression (MD).

Methods. A community-based random sample of 516 subjects, age 70 to 100 years and over, stratified by age and sex, was examined. All participants were investigated by psychiatrists and by geriatricians independently.

Results. In 16·5% (N = 85) of the study subjects SD was identified. Study subjects with SD had, similarly to the subjects with MD, significantly more somatic diagnoses and used more somatic as well as psychotropic medications than the subjects with NDS. Self-ratings and observer ratings of depression indicated that SD was a milder depressive state than MD.

Conclusions. Compared with MD, SD is probably a milder form of depression. The increased use of psychotropic medications indicates that at least a portion of these individuals have a disorder requiring treatment. One of the characteristics of SD is co-morbidity with somatic illnesses and physical disability.

Background. Although lifetime major depression (LTMD) is assessed with only moderate reliability in community samples, some predictors have emerged for ‘reliable’ LTMD. Given the large impact of sex on risk for LTMD, it is of interest to know if there are sex differences in the reliability of LTMD and its predictors.

Methods. A total of 5603 members of male–male and male–female twin pairs from a population-based registry were interviewed twice with a mean inter-interview interval of 19 months. LTMD was assessed on each occasion using DSM-III-R criteria. Univariate and multivariate logistic regression analyses were used, combining forward and back-prediction.

Results. The long-term test–retest reliability of LTMD was moderate (κ = +0·48) and did not differ significantly between males and females. In a multivariate model, the significant predictors of a stable diagnosis of LTMD, none of which differed across sex, were younger age at onset, older current age, history of treatment, increasing number of symptoms, level of impairment or level of distress, longer duration of episodes, higher current level of depression and the presence during the depressive episode of sad mood, weight loss, hypersomnia or fatigue. Using these variables, it was not possible to predict ‘stably diagnosed’ LTMD with both high sensitivity and high specificity.

Conclusion. In community samples, LTMD is diagnosed with moderate reliability. Although diagnostic stability can be predicted by variables related to severity, distress and treatment-seeking (probably acting to make depressive episodes more ‘memorable’), highly accurate prediction of stably diagnosed cases is not possible. Long-term recall is also significantly influenced by current symptoms. Neither the stability of LTMD nor its predictors differ in men and women.

Background. Stressful life events, such as family conflicts, separation, bereavement, somatic illness and financial problems are common antecedents of suicide. Studies on suicide among younger persons dominate the literature, despite the fact that a large proportion of suicides occur among elderly persons.

Methods. The occurrence of stressful life events was investigated among elderly suicide cases and population controls. The study was conducted in the southwestern part of Sweden and included 85 persons (46 males and 39 females) 65 years and above who had committed suicide from January 1994 to May 1996. Population controls (84 males and 69 females) were randomly selected. Interviews were carried out with the controls and with informants for the suicide cases. Questions on sociodemographic background, mental and somatic health status, and life events (0–6, 7–12 and 13–24 months preceding suicide/interview) were included in the interviews.

Results. Somatic illness, family discord and financial trouble were significant risk factors during all three time periods. Other risk factors were mental disorder, lower education, feelings of loneliness and previous suicide in the family. Factors associated with a decreased risk included active participation in organizations and having a hobby. Variables that remained in the multivariate logistic regression model were mental disorder (men, odds ratio (OR) = 62·4, 95% CI 17·9–217·5; women, OR = 55·9, 95% CI 14·1–222·3) and family discord (men, OR = 10·0, 95% CI 1·7–59·8; women, OR = 9·2, 95% CI 1·9–44·8).

Conclusions. Mental disorder and family discord were the two major risk factors for suicide among elderly men and women.

Background. There is considerable dispute about the validity of memory complaints. While some studies find that complaints are an early indicator of dementia or cognitive decline, there are also many studies showing that complaints are more closely associated with negative affect (depression, anxiety and neuroticism). The present paper used three-wave longitudinal data to test three hypotheses: (1) that memory complaints reflect an evaluation of present and past memory performance; (2) that memory complaints predict future memory performance; and (3) that memory complaints predict current and future negative affect.

Methods. A longitudinal study was carried out with a community sample of people aged 70 and over. Participants were assessed for memory complaints, memory performance and negative affect at three waves separated by 3·6 years and 4·0 years. There were 331 persons with data on all relevant variables. The data were analysed using structural equation modelling.

Results. Significant paths in the structural model were found from memory performance to future memory complaints, as well as from memory complaints to future memory performance, supporting hypotheses 1 and 2. Memory complaints were associated with current negative affect, but did not predict future negative affect.

Conclusions. Memory complaints do reflect perceptions of past memory performance and are also an early manifestation of memory impairment. However, current negative affect (anxiety and depression symptoms) shows the greatest association with memory complaints.

Background. Spiritual beliefs are rarely considered in psychological or medical publications. We recently published the psychometric properties of an interview designed to measure religious and spiritual belief. In this study, we aimed to develop this instrument further as a self-report questionnaire and to make it more comprehensive by including measurement of spiritual experiences in addition to faith or intellectual assent.

Methods. Based on extensive discussion with colleagues, advice from users of the interview and comments from respondents, a self-report format was designed. We then evaluated the final format of the questionnaire in terms of (1) patterns of response and demographic predictors of beliefs; (2) test–retest reliability and internal consistency; (3) criterion and internal validity; and (4) the nature of spiritual experiences and their relationship to beliefs and strength of beliefs.

Results. Two hundred and ninety-seven people took part in the validity and reliability tests of the questionnaire. Criterion validity, predictive validity, internal consistency and test–retest reliability were acceptably high. The instrument consistently differentiated between people with high and low spiritual beliefs.

Conclusions. This instrument is brief and simple to complete. We would recommend that measures of religious and/or spiritual belief like this be more widely applied in health services research as they evaluate aspects of people's lives that go somewhat further than health status or quality of life.

Background. Culture influences symptom presentation and help-seeking and may influence the general practitioner's assessment.

Methods. We recruited Punjabi and English GP attenders to a two-phase survey in London (UK) using the Amritsar Depression Inventory and the General Health Questionnaire as screening instruments. The Clinical Interview Schedule was the criterion measure. General practitioners completed Likert assessments.

Results. The second phase was completed by 209 Punjabi and 180 English subjects. The prevalence of common mental disorders was not influenced by culture. Punjabi cases more often had ‘poor concentration and memory’ and ‘depressive ideas’ but were not more likely to have somatic symptoms. General practitioners were more likely to assess Punjabis with common mental disorder as having ‘physical and somatic’ symptoms or ‘sub-clinical disorders’. Punjabi cases with depressive ideas were less likely to be detected compared with English ones. In comparison to English men, English women were under-detected by Asian general practitioners. Help-seeking English subjects were more likely to be correctly identified as cases.

Conclusions. The prevalence of common mental disorders and somatic symptoms does not differ across cultures. Among English subjects, general practitioners were more likely to identify correctly pure psychiatric illness and mixed pathology; but Punjabi subjects with common mental disorders were more often assessed as having ‘sub-clinical disorders’ and ‘physical and somatic’ disorders. English women were less well detected than English men. English help-seeking cases were more likely to be detected.

Background. The National Adult Reading Test (NART) is widely used in research and clinical practice as an estimate of pre-morbid or prior ability. However, most of the evidence on the NART's validity as a measure of prior intellectual ability is based on concurrent administration of the NART and an IQ measure.

Method. We followed up 179 individuals who had taken an IQ test (the Moray House Test) at age 11 and administered the NART and the Mini-Mental State Examination (MMSE) at age 77. A subset (N=97) were also re-administered the original IQ test.

Results. The correlation between NART performance at age 77 and IQ age 11 was high and statistically significant (r=0·73; P<0·001). This correlation was comparable to the correlation between NART and current IQ, and childhood IQ and current IQ, despite the shared influences on the latter variable pairings. The NART had a significant correlation with the MMSE but this correlation fell to near zero (r=0·02) after partialling out the influence of childhood IQ.

Discussion. The pattern of results provides strong support for the claim that the NART primarily indexes prior (rather than current) intellectual ability.

Background. Neuropsychiatric research needs to examine the relationships between aetiological, genotypic and clinical risk factors and behavioural phenotypes. These relationships can now be examined in older patients with depressive disorders.

Methods. Key behavioural features, clinical and vascular risk factors and putative genotypes for late-onset neurodegenerative disorders and/or vascular disease were recorded in 78 older patients with depression (mean age = 54·9 years, S.D. = 14·1) and 22 healthy control subjects (mean age = 55·5 years, S.D. = 9·6).

Results. Two or more vascular risks were more common in older patients (65% v. 26% of control subjects, P < 0·01), and in patients with late-onset disorders (82% v. 57% in patients with early-onset disorders, P < 0·05). Patients with late-onset depression had a higher prevalence of the homozygous or heterozygous forms of the C677T mutation of the methylenetetrahydrofolate reductase enzyme (MTHFR)(74% v. 48% in patients with early-onset disorders, P < 0·05). In a multivariate model, only presence of the MTHFR gene mutation predicted late-onset depression (odds ratio = 3·8, 95% CI = 1·1–12·9). Neither apolipoprotein E epsilon 4 or epsilon 2 was associated with depression, late-onset depression, cognitive impairment, or psychomotor change. Patients with apolipoprotein E epsilon 4 were less likely to have psychotic forms of depression.

Conclusions. Patients with late-onset depression had an increased rate of the C677T MTHFR gene mutation and other vascular risk factors. This suggests that a proportion of these patients may have genetically-determined and/or other vascular aetiologies. Patients at risk of these disorders may be assisted by currently-available preventative strategies.

Background. Possible adverse health effects due to mercury released by amalgam fillings have been discussed in several studies of patients who attribute various symptoms to the effects of amalgam fillings. No systematic relation of specific symptoms to increased mercury levels could be established in any of these studies. Thus, a psychosomatic aetiology of the complaints should be considered and psychological factors contributing to their aetiology should be identified.

Methods. A screening questionnaire was used to identify subjects who were convinced that their health had already been affected seriously by their amalgam fillings (N = 40). These amalgam sensitive subjects were compared to amalgam non-sensitive subjects (N = 43). All participants were subjected to dental, general health, toxicological and psychological examinations.

Results. The two groups did not differ with respect to the number of amalgam fillings, amalgam surfaces or mercury levels assessed in blood, urine or saliva. However, amalgam sensitive subjects had significantly higher symptom scores both in a screening instrument for medically unexplained somatic symptoms (SOMS) and in the SCL-90-R Somatization scale. Additionally, more subjects from this group (50% versus 4·7%) had severe somatization syndromes. With respect to psychological risk factors, amalgam sensitive subjects had a self-concept of being weak and unable to tolerate stress, more cognitions of environmental threat, and increased habitual anxiety. These psychological factors were significantly correlated with the number and intensity of the reported somatic symptoms.

Conclusions. While our results do not support an organic explanation of the reported symptoms, they are well in accord with the notion of a psychological aetiology of the reported symptoms and complaints. The findings suggest that self-diagnosed ‘amalgam illness’ is a label for a general tendency toward somatization.

Background. The prescription of antidepressants has increased substantially over the last 10 years. It is therefore timely to examine trends in mortality associated with overdoses of antidepressants and to compare the relative mortality associated with different antidepressants.

Methods. Data were derived from a newly developed national database of deaths from overdose and poisoning in England and Wales between 1993 and 1997. Age and sex specific death rates associated with overdose and poisoning with antidepressants were calculated together with numbers of deaths per 100000 prescriptions of individual antidepressants.

Results. Twenty per cent (2503) of all deaths from overdose or poisoning were antidepressant related. The number of deaths increased by 18% between 1993 and 1997. Ninety-five per cent of deaths from antidepressants were associated with tricyclic antidepressants, particularly dothiepin and amitriptyline. Tricyclic antidepressants were associated with 5·3 deaths per 100000 prescriptions, 4·4 for monoamine oxidase inhibitors and 0·4 for selective serotonin reuptake inhibitors. Annual death rates were highest in men aged 30–44 years (18·2 per million) and women aged 45–59 years (14·8). Death rates from antidepressants were 2·5 times higher in the most deprived fifth than in the least deprived fifth of enumeration districts.

Conclusions. Antidepressants are an important cause of death from poisoning and overdose. SSRIs and newer antidepressants are associated with <10% of the risk of death than the older antidepressants. There is a strong association between area deprivation and deaths from antidepressants.

Background. Current cognitive theories propose that depression develops as a result of the interaction between dysfunctional cognitive schemata and environmental stressors. There is also consistent evidence of a substantial genetic contribution to depression. This study examines the familiality and stability of dysfunctional attitudes and attempts to distinguish whether they reflect trait vulnerability to depression or the state of being depressed.

Method. The 24-item Dysfunctional Attitude Scale (DAS-24) was completed by 108 depressed probands and their nearest-aged siblings and 105 healthy control probands and their nearest-age siblings, at the time of a semi-structured clinical interview and 10–12 months later. Subjects also completed self-report measures of depressed mood on both occasions.

Results. Measures of clinical depression were significantly correlated with DAS scores. At retest, DAS scores remained elevated despite improvement in mood, giving support for earlier findings, that dysfunctional attitudes remain active following recovery.

The dependency subscale (DAS-D) of the DAS showed modest familiality, although there were no significant differences for DAS-D scores between the two groups of siblings. In a multiple regression analysis, current mood-state was the overwhelming predictor of DAS scores. However for DAS-D, gender as well as current mood influenced scores on this subscale.

Conclusion. Although there was modest evidence for temporal stability and familiality for some DAS-24 subscale scores, dysfunctional attitudes were predominantly influenced by current low mood, and therefore reflect the state of being depressed rather than a familial vulnerability trait underpinning depression.

Background. Geographic variations in the incidence of deliberate self-harm (DSH) and suicide have been shown to be associated with area-based measures of socio-economic deprivation and social fragmentation. Previous studies have been subject to methodological limitations. None has investigated whether ecological associations are reflected in characteristics of individuals involved in suicidal behaviour.

Methods. DSH patients presenting to a general hospital between 1985 and 1995 and suicides (including open verdicts) from the same catchment area were studied. Mean annual rates of DSH and suicide by gender were calculated for electoral wards. The wards were amalgamated into 20 groups according to their ranking for socio-economic deprivation (Townsend) and social fragmentation scores. Associations of these variables with DSH and suicide rates were investigated. Characteristics of DSH patients living in ward groups with the highest and lowest socio-economic deprivation and social fragmentation scores were compared.

Results. Socio-economic deprivation was associated with DSH rates among males (r = 0·89) and females (r = 0·87). After controlling for social fragmentation the associations remained relatively strong, particularly in young males. Associations with social fragmentation in both genders (males, r = 0·83; females, r = 0·86) were attenuated after controlling for socio-economic deprivation. For suicide, the only significant association was with socio-economic deprivation in males (r = 0·79), but this was attenuated after controlling for social fragmentation. The characteristics of individual DSH patients reflected those of the areas where they lived.

Conclusions. Reducing socio-economic deprivation and its associated problems may be an important strategy in the prevention of suicidal behaviour, especially in young men.

Background. The clinician-administered version of the Liebowitz Social Anxiety Scale (LSAS-CA) is a commonly used assessment device for the evaluation of social anxiety disorder and has been shown to have strong psychometric characteristics. Because of its apparently straightforward rating format and potential savings in time and effort, interest in the use of the LSAS as a self-report (LSAS-SR) measure has increased, and the LSAS-SR has been used in a number of studies. However, the psychometric properties of the LSAS-SR have not been well established.

Methods. This study examined the psychometric properties of the LSAS-SR in comparison to the LSAS-CA in a sample of 99 individuals with a primary diagnosis of social anxiety disorder and 53 individuals with no current psychiatric disorder.

Results. There was little difference between the two versions of the LSAS on any scale or subscale score. Both forms were internally consistent and the subscale intercorrelations for the two forms were essentially identical. Correlations of each LSAS-SR index with its LSAS-CA counterpart were all highly significant. Finally, the convergent and discriminant validity of the two forms of the LSAS was shown to be strong.

Conclusion. Results of this study suggest that the self-report version of the LSAS compares well to the clinician-administered version and may be validly employed in the assessment of social anxiety disorder.

Background. Depression is a common problem in patients with Parkinson's disease, but its mechanism is poorly understood. It is thought that neurochemical changes contribute to its occurrence, but it is unclear why some patients develop depression and others do not. Using a community-based sample of patients with Parkinson's disease, we investigated the contributions of impairment, disability and handicap to depression in Parkinson's disease.

Methods. Ninety-seven patients seen in a population-based study on the prevalence of Parkinson's disease completed the Beck Depression Inventory (BDI). Clinical and historical information on symptoms and complications of Parkinson's disease were obtained from the patients by a neurologist. In addition, clinician and patient ratings of disability on the Schwab and England scale were obtained and a quality of life questionnaire was completed.

Results. Moderate to severe depression (BDI [ges ] 18) was reported by 19·6% of the patients. Higher depression scores were associated with advancing disease severity, recent self-reported deterioration, higher akinesia scores, a mini-mental score of < 25 and occurrence of falls. Disability as rated by the neurologist accounted for 34% of the variance of depression scores. Self-reported impairment of cognitive function and the feeling of stigmatization accounted for > 50% of the variance of depression scores.

Conclusions. Depression in patients with Parkinson's disease is associated with advancing disease severity, recent disease deterioration and occurrence of falls. Regression analysis suggests that depression in Parkinson's disease is more strongly influenced by the patients' perceptions of handicap than by actual disability. The treatment of depression should therefore be targeted independently of treatment of the motor symptoms of Parkinson's disease, and consider the patients' own perception of their disease.

Background. Previous research suggests that children are a high risk group vulnerable to the effects of chronic noise exposure. However, questions remain about the nature of the noise effects and the underlying causal mechanisms. This study addresses the effects of aircraft noise exposure on children around London Heathrow airport, in terms of stress responses, mental health and cognitive performance. The research also focuses on the underlying causal mechanisms contributing to the cognitive effects and potential confounding factors.

Methods. The cognitive performance and health of 340 children aged 8–11 years attending four schools in high aircraft noise areas (16h outdoor Leq>66dBA) was compared with children attending four matched control schools exposed to lower levels of aircraft noise (16h outdoor Leq<57dBA). Mental health and cognitive tests were group administered to the children in the schools. Salivary cortisol was measured in a subsample of children.

Results. Chronic aircraft noise exposure was associated with higher levels of noise annoyance and poorer reading comprehension measured by standardized scales with adjustments for age, deprivation and main language spoken. Chronic aircraft noise was not associated with mental health problems and raised cortisol secretion. The association between aircraft noise exposure and reading comprehension could not be accounted for by the mediating role of annoyance, confounding by social class, deprivation, main language or acute noise exposure.

Conclusions.These results suggest that chronic aircraft noise exposure is associated with impaired reading comprehension and high levels of noise annoyance but not mental health problems in children.

Background. The efficacy and effectiveness of cognitive therapy (CT) is well established for unipolar disorders, but little is known about its utility in bipolar disorders. This study aimed to explore the feasibility and efficacy of using CT as an adjunct to usual psychiatric treatment in this patient population.

Method. Subjects referred by general adult psychiatrists were assessed by and independent rater and then randomly allocated to immediate CT (N=21) or 6-month waiting-list control, which was then followed by CT (N=21). Observer and self-ratings of symptoms and functioning were undertaken immediately prior to CT, after a 6-month course of CT and a further 6-months later. Data on relapse and hospitalization rates in the 18 months before and after commencing CT were also collected.

Results. At 6-month follow-up, subjects allocated to CT showed statistically significantly greater improvements in symptoms and functioning as measured on the Beck Depression Inventory, the Internal State Scale, and the Global Assessment of Functioning than those in the waiting-list control group. In the 29 patients who eventually received CT, relapse rates in the 18 months after commencing CT showed a 60% reduction in comparison with the 18 months prior to commencing CT. Seventy per cent of subjects who commenced therapy viewed CT as highly acceptable.

Conclusion. Although the results of this study are encouraging, the use of CT in subjects with bipolar disorders is more complex than in unipolar disorders and requires a high level of therapist expertise. The therapy may prove to be particularly useful in the treatment of bipolar depression.

Background. An international, multi-site study funded by the Price Foundation has collected 237 affected relative pairs to identify potential genetic factors that may contribute to the pathogenesis of anorexia nervosa (AN). The current report utilized this sample to derive phenotypes from the personality and behavioural traits assessed in a large number of individuals with eating disorders.

Methods. Multivariate analytical techniques were used to characterize the relationships among personality (e.g. trait anxiety, perfectionism, harm avoidance, novelty seeking) and behavioural traits (obsessions and compulsions) in individuals with eating disorders (primarily AN; N = 348) and assess the effectiveness of these traits in classifying subjects into diagnostic subtypes.

Results. Factor analysis revealed that the most influential factor was one of trait anxiety, harm avoidance, perfectionism, obsessive–compulsive behaviours, and diminished self-directedness, although the precise nature of this factor differed slightly across sites. Discriminant analysis was used to evaluate the utility of these personality/behavioural factors in predicting subdiagnosis. Overall, the misclassification rate was 34 %; however, there was an 80 % rate of accurate classification of those individuals with a diagnosis of restricting-type AN.

Conclusions. Trait anxiety, harm avoidance, perfectionism, obsessive–compulsive behaviours and diminished self-directedness may best be conceptualized as parts of the same underlying construct among individuals with eating disorders, particularly AN. These personality and behavioural traits were also found to be of some utility in classifying eating disordered individuals into diagnostic subgroups, particularly those with restricting-type AN. We expect these phenotypic findings to benefit our ongoing search for genetic loci underlying the liability to eating disorders.

Background. It is not known if a subject's characteristic level of self-rated depression symptoms index their genetic or environmental liability to major depressive disorder when measurement error and other occasion-specific influences are taken into account.

Method. Monozygotic (N = 408) and dizygotic (N = 295) adult female twin pairs from a population-based registry were surveyed twice with an average follow-up interval of 61 months. At each occasion subjects completed a structured clinical interview (SCID) to assess lifetime history of major depression and the subject-rated Symptom Check List (SCL) to assess current level of depressive symptomatology. A bivariate measurement model was used to estimate the genetic and environmental correlations between liability to reliably diagnosed lifetime history of major depression and the characteristic or temporally stable SCL depression score.

Results. The genetic and non-familial environmental correlation between liability to reliably diagnosed major depression and the characteristic level of SCL depression symptoms (and the proportion of variance shared between measures) is +0·70 and +0·24 respectively.

Conclusions. When allowance is made for diagnostic unreliability and temporal fluctuations in the level of subject-rated symptoms, 70% of the variance in genetic risk factors and 24% of the variance in environmental risk factors is shared by a diagnosis of lifetime major depression and total SCL depression symptom score. SCL depression scores may therefore be a useful screening measure for many of the genetic risk factors which influence liability to major depression.