Employment Grade Research Articles

Is the SF-36 a valid measure of change in population health? Results from the Whitehall II study

Objective: To measure within-person change in scores on the short form general health survey (SF-36) by age, sex, employment grade, and disease status.Design: Longitudinal study with a mean of 36...

Social inequality in coronary risk: central obesity and the metabolic syndrome. Evidence from the Whitehall II study.

This report describes the social distribution of central obesity and the metabolic syndrome at the Whitehall II study phase 3 examination, and assesses the contribution of health related behaviours to their distribution. Cross-sectional analyses were conducted utilising data collected in 1991-1993 from 4978 men and 2035 women aged 39-63 years who completed an oral glucose tolerance test. There was an inverse social gradient in prevalence of the metabolic syndrome. The odds ratio (95% confidence interval) for having the metabolic syndrome comparing lowest with highest employment grade was: men 2.2 (1.6-2.9), women 2.8 (1.6-4.8). Odds ratios for occupying the top quintile of the following variables, comparing lowest with highest grade, were, for waist-hip ratio: men 2.2 (1.8-2.8), women 1.6 (1.1-2.4); post-load glucose: men 1.4 (1.1-1.8), women 1.8 (1.2-2.6); triglycerides: men 1.6 (1.2-2.0), women 2.2 (1.5-3.3); fibrinogen: men 1.7 (1.4-2.3), women 1.9 (1.2-2.8). Current smoking status, alcohol consumption and exercise level made a small contribution (men 11%, women 9%) to the inverse association between socioeconomic status and metabolic syndrome prevalence. In conclusion, central obesity, components of the metabolic syndrome and plasma fibrinogen are strongly and inversely associated with socioeconomic status. Our findings suggest the metabolic syndrome may contribute to the biological explanation of social inequalities in coronary risk. Health related behaviours appear to account for little of the social patterning of metabolic syndrome prevalence.

The impact of socioeconomic status on health functioning as assessed by the SF-36 questionnaire: the Whitehall II Study.

This study measured the association between socioeconomic status and the eight scale scores of the Medical Outcomes Study short form 36 (SF-36) general health survey in the Whitehall II study of British civil servants. It also assessed, for the physical functioning scale, whether this association was independent of disease. A questionnaire containing the SF-36 was administered at the third phase of the study to 5766 men and 2589 women aged 39 through 63 years. Socioeconomic status was measured by means of six levels of employment grades. There were significant improvements with age in general mental health, role-emotional, vitality, and social functioning scale scores. In men, all the scales except vitality showed significant age-adjusted gradients across the employment grades (lower grades, worse health). Among women, a similar relationship was found for the physical functioning, pain, and social functioning scales. For physical functioning, the effect of grade was found in those with and without disease. Low socioeconomic status was associated with poor health functioning, and the effect sizes were comparable to those for some clinical conditions. For physical functioning, this association may act both via and independently of disease.

Contribution of job control and other risk factors to social variations in coronary heart disease incidence

The first Whitehall Study showed an inverse social gradient in mortality from coronary heart disease (CHD) among British civil servants--namely, that there were higher rates in men of lower employment grade. About a quarter of this gradient could be attributed to coronary risk factors. We analysed 5-year CHD incidence rates from the Whitehall II study to assess the contribution to the social gradient of psychosocial work environment, social support, coronary risk factors, and physical height. Data were collected in the first three phases of examination of men and women in the Whitehall II study. 7372 people were contacted on all three occasions. Mean length of follow-up was 5.3 years. Characteristics from the baseline, phase 1, questionnaire, and examination were related to newly reported CHD in people without CHD at baseline. Three self-reported CHD outcomes were examined: angina and chest pain from the Rose questionnaire, and doctor-diagnosed ischaemia. The contribution of different factors to the socioeconomic differences in incident CHD was assessed by adjustment of odds ratios. Compared with men in the highest grade (administrators), men in the lowest grade (clerical and office-support staff) had an age-adjusted odds ratio of developing any new CHD of 1.50. The largest difference was for doctor-diagnosed ischaemia (odds ratio for the lowest compared with the highest grade 2.27). For women, the odds ratio in the lowest grade was 1.47 for any CHD. Of factors examined, the largest contribution to the socioeconomic gradient in CHD frequency was from low control at work. Height and standard coronary risk factors made smaller contributions. Adjustment for all these factors reduced the odds ratios for newly reported CHD in the lowest grade from 1.5 to 0.95 in men, and from 1.47 to 1.07 in women. Much of the inverse social gradient in CHD incidence can be attributed to differences in psychosocial work environment. Additional contributions were made by coronary risk factors--mainly smoking--and from factors that act early in life, as represented by physical height.

Sickness absence from back pain, psychosocial work characteristics and employment grade among office workers.

The relation between psychosocial work characteristics, employment grade, and sickness absence due to back pain was studied among office workers. Base-line questionnaire data and sickness absence data collected continuously with a mean of 4 years of follow-up were analyzed. The subjects were 6894 men and 3414 women aged 35 to 55 years at recruitment. The main outcome measures were short (< or = 7 days) and long (> 7 days) absences due to back pain. There was a strong inverse association between employment grade and rate of absences due to back pain (P for linear trend < 0.001); for example, the rate ratio for short absences among the men in a comparison of lowest versus highest employment grade was 8.21. The age adjusted rate ratio for the effect of low versus high control over work among the men was 2.22 [95% confidence interval (95% CI) 1.77-2.79] for short and 1.61 (95% CI 1.01-2.58) for long absences due to back pain. For short absences due to back pain among the men in high grades of employment, the rate ratio for low control was 3.42 compared with 0.78 for the lower grades (P for interaction < 0.001). For the women the corresponding rate ratios were 0.80 and 1.35, respectively (P for interaction 0.08). Absence from work due to back pain was strongly inversely related to employment grade. The effects of psychosocial work characteristics-particularly control-differed by grade and gender in magnitude and direction. The psychosocial work environment represents a potentially reversible cause of ill health.

Low job control and risk of coronary heart disease in whitehall ii (prospective cohort) study

Objective: To determine the association between adverse psychosocial characteristics at work and risk of coronary heart disease among male and female civil servants.Design: Prospective cohort study (Whitehall II study). At...

Do socioeconomic differences in mortality persist after retirement? 25 year follow up of civil servants from the first Whitehall study.

To assess the risk of death associated with work based and non-work based measures of socioeconomic status before and after retirement age. Follow up study of mortality in relation to employment grade and car ownership over 25 years. The first Whitehall study. 18,133 male civil servants aged 40-69 years who attended a screening examination between 1967 and 1970. Death. Grade of employment was a strong predictor of mortality before retirement. For men dying at ages 40-64 the lowest employment grade had 3.12 times the mortality of the highest grade (95% confidence interval 2.4 to 4.1). After retirement the ability of grade to predict mortality declined (rate ratio 1.86; 1.6 to 2.2). A non-work based measure of socioeconomic status (car ownership) predicted mortality less well than employment grade before retirement but its ability to predict mortality declined less after retirement. Using a relative index of inequality that was sensitive to the distribution among socioeconomic groups showed employment grade and car ownership to have independent associations with mortality that were of equal magnitude after retirement. The absolute difference in death rates between the lowest and highest employment grades increased with age from 12.9 per 1000 person years at ages 40-64 to 38.3 per 1000 at ages 70-89. Socioeconomic differences in mortality persist beyond retirement age and in magnitude increase with age. Social differentials in mortality based on an occupational status measure seem to decrease to a greater degree after retirement than those based on a non-work measure. This suggests that alongside other socioeconomic factors work itself may play an important part in generating social inequalities in health in men of working age.

Childhood social circumstances and psychosocial and behavioural factors as determinants of plasma fibrinogen

Summary Background High plasma fibrinogen concentration is associated with an increased risk of coronary heart disease. We have investigated associations between plasma fibrinogen and factors operating in childhood and in adulthood, including the psychosocial characteristics of work. Methods In a cross-sectional study of Civil Servants in London, UK, 2095 men and 1202 women aged 45-55 years provided blood samples for fibrinogen measurement at the time of the Whitehall II study baseline. The participants completed a questionnaire on demographic characteristics, education, employment grade, parents' occupation, health behaviours, and work characteristics. Findings Measures of childhood environment (adult height, father's social class, and participant's education) were inversely associated with adult plasma fibrinogen concentration in both sexes. Lower socioeconomic status (as shown by employment grade) was associated with higher fibrinogen concentrations, with differences from top to bottom grade of 0·22 g/L (95% Cl 0·13-0·31) in men and 0·37 g/L (0·18-0·56) in women (p<0·0001, both sexes). This association was not accounted for by measures of childhood circumstances. Control over work, assessed by personnel managers, was inversely related to fibrinogen in both sexes, and a similar relation was seen for self-rated control over work among men but not women. Men in the bottom third of the distribution for self-rated and externally assessed control over work had higher fibrinogen concentrations than those in the top third for both measures (difference 0·16 g/L [0·07-0·26]; p<0·001). There was no difference between these extremes among women (0·02 g/L [-0·16 to 0·19]). Current smokers had higher fibrinogen concentrations than non-smokers, and moderate alcohol consumers had lower concentrations than those who drank occasionally or never. Interpretation Although our study was cross-sectional, it provides evidence that adult fibrinogen concentration is determined by factors operating throughout life. Fibrinogen may be a marker of the biological pathways that mediate the inverse socioeconomic gradient in coronary disease.

Psychosocial work environment and sickness absence among British civil servants: the Whitehall II study.

This study sought to examine the association between the psychosocial work environment and subsequent rates of sickness absence. The analyses were based on a cohort of male and female British civil servants (n=9072). Rates of short spells (<or=7 days) and long spells (>7 days) of sickness absence were calculated for different aspects of the psychosocial work environment, as measured by self-reports and personnel managers' ratings (external assessments). Low levels of work demands, control, and support were associated with higher rates of short and long spells of absence in men and, to a lesser extent, in women. The differences were similar for the self-reports and external assessments. After adjustment for grade of employment, the differences were diminished but generally remained significant for short spells. The combination of high demands and low control was only associated with higher rates of short spells in the lower grades. The psychosocial work environment predicts rates of sickness absence. Increased levels of control and support at work could have beneficial effects in terms of both improving the health and well-being of employees and increasing productivity.

Possible Link between Social and Biologic Factors in the Epidemiology of Coronary Artery Disease

Visiting Scholar, New England Medical Center #345, 750 Washington Street, Boston, Massachusetts 02111.To the Editor:--Investigators interested in the health of populations continue to look for biologic pathways that can connect some of the social determinants of health with the production of disease. [1]The results reported by Rosenfeld et al. [2]show that plasma fibrinogen concentration increases in human subjects after the infusion of epinephrine, cortisol, or glucagon may add to the understanding of how certain social factors are biologically related to the development of coronary artery disease.Data from the Northwick and Framingham studies [3,4]and other epidemiologic evidence reviewed by Ernst [5]indicate that plasma fibrinogen concentrations can be used to predict coronary artery disease with predictive power as high as more generally accepted risk factors.Marmot et al. [6]have shown that mortality from coronary artery disease is inversely related to employment grade with a relative risk more than three times greater in the lowest grade of employment compared with the highest grade. Markowe et al. [7]reported significant differences in plasma fibrinogen concentrations between men in the lowest grades of employment and those in the highest classifications. They also demonstrated a positive correlation between the workers' fibrinogen concentrations and the stress of their respective jobs as determined by a questionnaire composed of items that had been shown to identify stress related to increased risk of coronary artery disease.Combining the findings of Rosenfeld et al. with the epidemiologic data prompts the speculation that lower social class and employment grade produce stress leading to an increase in circulating epinephrine, which results in increased plasma fibrinogen concentration, which in turn is predictive of coronary artery disease and perhaps causally related.John C. Ribble, M.D., Visiting Scholar, New England Medical Center #345, 750 Washington Street, Boston, Massachusetts 02111.

Sickness absence as a measure of health status and functioning: from the UK Whitehall II study.

To investigate the relationship between self reported health status and sickness absence. Analysis of questionnaire and sickness absence data from the first phase of the Whitehall II study--a longitudinal study set up to investigate the degree and causes of the social gradient in morbidity and mortality. London offices of 20 civil service departments. Altogether 6895 male and 3413 female civil servants aged 35-55 years. Analysis was conducted on 88% of participants who had complete data for the present analysis. A strong inverse relation between the grade of employment (measure of socioeconomic status) and sickness absence was observed. Men in the lowest grade had rates of sickness absence six times higher than those in the highest grade. For women the corresponding differences were two to five times higher. In general, the longer the duration of absence, the more strongly did baseline health predict rates of absence. However, the health measures also predicted shorter spells, although to a lesser extent. Job satisfaction was strongly related to sickness absence with higher rates in those who reported low job satisfaction. After adjusting for health status the association remained for one to two day absences, but was greatly reduced for absences longer than three days. There was a strong association between ill health and sickness absence, particularly for longer spells. The magnitude of the association may have been underestimated because of the strength of the association between grade of employment and sickness absence. It is proposed that sickness absence be used as an integrated measure of physical, psychological, and social functioning in studies of working populations.

Work characteristics and psychiatric disorder in civil servants in London.

To describe the association between self reported and externally assessed work characteristics and psychiatric disorder. Analysis of questionnaire data collected from the first phase of the Whitehall II study, a cohort study of an employed population. Twenty civil service departments in London. Altogether 6900 male and 3414 female civil servants aged 35-55 years. High levels of subjective social support at work, control at work, job variety, and skill use were associated with greater satisfaction and wellbeing and less psychiatric disorder measured by the 30 item general health questionnaire (GHQ). High levels of subjective work pace and conflicting demands were associated with less satisfaction and wellbeing and greater psychiatric disorder. The combined effects of work characteristics were similar to the effects of the work characteristics considered separately, except that for men there was a small interaction between psychological demands and control on the GHQ. There was little overall support for the two factor job strain model. In contrast, objective indices of work were generally not associated with the psychological indices. Findings in men and women were generally comparable and were not significantly influenced by employment grade. Negative affectivity and a tendency to report negatively about both work and the psychological indices may partly explain the difference in the findings between subjective and objective work characteristics. However, subjective work characteristics were still associated with psychiatric disorder after adjusting for negative affectivity. The potential confounding effects of employment grade did not explain the association between either subjective or objective work characteristics and the psychological indices. While modifications to the work environment may directly reduce certain adverse physical health effects, the influence of work place design and management on psychological wellbeing, satisfaction, and psychiatric disorder may be mediated through subjective perceptions of the work environment.

Sickness absence for psychiatric illness: The Whitehall II study

Over the past 20 years, rates of sickness absence have increased and psychiatric disorders have become an important cause of sickness absence. The socio-demographic associations for psychiatric sickness absence are reported from the Whitehall II study, a longitudinal survey of 10,308 London-based male and female civil servants between 35–55 years. Short spells (⩽ 7 days), long spells (> 7 days) and very long spells (> 21 days) of sickness absence were examined in 5620 civil servants for whom reason for absence was available in civil service records. Civil service coding of reasons for absence was validated against report of general practitioners' diagnoses. Psychiatric disorder, largely neurosis and neurosis ill-defined, was the third most common cause of long spells of sickness absence in women and the fourth most common in men. For both men and women it was the second most common cause of very long spells of absence. Psychiatric sickness absence for short, long and very long spells was more frequent in lower employment grades than higher employment grades in keeping with the pattern for other illnesses. This partly explains the higher rate of sickness absence in women than men. Widowed and single men, and divorced women had high rates of psychiatric sickness absence. Comparing reason codes based on sickness certificates with general practitioners reports, there appeared to be evidence of under-reporting of psychosis on certificates. The general rise in levels of sickness absence and in particular psychiatric sickness absence may have several explanations: increased recognition of psychiatric disorder; greater reporting of psychiatric disorder; a real increase in the incidence of psychiatric disorder; or a change in employment opportunities for individuals with minor psychiatric disorder. The contribution of psychiatric disorder to the overall burden of sickness absence is likely to be underestimated. It is argued that greater preventative effort examining working conditions and social supports and earlier recognition and treatment of existing psychiatric disorder will lead to a reduction in sickness absence.

The assessment of biological age: a report from the Department of Environment Study.

Indicators of ageing were measured in 397 male and 130 female London Civil Servants aged from 37 to 58 years of age. Grey hair, skin inelasticity, and arcus senilis were strongly and independently related to chronological age. Also independently related were serum albumin (negatively related in both sexes), baldness, serum creatinine, systolic blood pressure, serum calcium (negatively) and ESR in men, and serum cholesterol in women. Chronological age was regressed on the above variables for men and women separately to provide regression equations. Biological age for an individual was calculated by entering his or her results and calculating the residuals. Biological age in those who stopped smoking tended to be younger than chronological age by an average of 12-13 months in men and 1-4 months in women. Men and women who had never smoked had higher biological than actual ages but not after adjusting for regression dilution bias. Men who currently smoked had higher biological ages of 2-3 months but not women smokers (4-6 months lower). Similarly, men of lower employment grades had an average biological age 13 months older and women 8 months, compared with higher employment grades. These differences between employment grade appeared to be due to ESR, arcus senilis, systolic blood pressure and serum cholesterol. These four measurements may be markers of biological rather than chronological age, and the value of attempting to measure biological age is discussed.

An investigation of brain tumours and other malignancies in an agricultural research institute.

A historical cohort study was carried out in an agricultural research institute in the Republic of Ireland to investigate a perceived excess of cancer deaths among employees. The objectives of the study were (a) to confirm whether or not total or cause specific death rates among selected employees were higher than expected based on national figures, and to quantify any excess, and (b) to identify centres and employee grades associated with any excess risk. The cohort comprised all administrative, research, and technical staff employed for at least two years between 1960 and 1980, giving a final total for analysis of 1323 employees. Employment history was categorised by place of work and employment grade. Deaths among the cohort were identified and causes of deaths verified. Overall the cohort had a lower than expected mortality compared with national rates (O/E = 0.67). Female deaths were too few for analysis but, among the male employees, there was an excess of all cancers (O/E = 1.24; 95% confidence interval (95% CI) 0.8-1.9), in particular brain cancer (O/E = 4.69; 95% CI 1.2-11.4) and bladder cancer (O/E = 9.31, 95% CI 1.9-27.2). The pattern of brain tumour deaths was consistent with an occupational aetiology but it was not possible to identify specific exposures associated with the excess. All four cases occurred among research workers in the plant and soil science area. The pattern of bladder cancers was difficult to interpret. The authors are at present participating in a multicentre study to further investigate cancer risk in laboratory workers.

Gender and employment grade differences in blood cholesterol, apolipoproteins and haemostatic factors in the Whitehall II study

In the first Whitehall study, plasma cholesterol was a strong predictor of coronary heart disease (CHD) but it showed a positive association with grade of employment: the higher the grade.the higher the level. Because it could not explain the higher rate of CHD in lower employment grades, further investigation of biochemical CHD risk factors has been conducted with data from the baseline examination of the Whitehall II cohort in 1985-88. These data also allow investigation of gender differences and the effect of menopause. Serum cholesterol (6860 men and 3374 women) and apolipoproteins A-I and B (apo Al and apo B) were measured in those aged 35–55 working in the London offices of twenty Civil Service departments. Plasma fibrinogen and factor VII were determined in 45–55 year olds. The apo B/apo AI ratio (95% confidence interval) after age adjustment is lowest in premenopausal women: 0.557 (0.549-0.565), intermediate in postmenopausal women: 0.601 (0.589-0.613) and highest in men: 0.703 (0.698-0.709). After age adjustment fibrinogen is higher in postmenopausal (2.90 (2.85-2.95) g/1) than in premenopausal women (2.78 (2.71-2.84) g/1), who have higher levels than men (2.64 (2.62-2.67) g/1). A positive association with employment grade is seen for apo AI and a negative association is seen for fibrinogen, apo B (women only) and the apo B/apo AI ratio, after age adjustment. These patterns are consistent with the higher rates of CHD in lower grades. Cholesterol and factor VII show no gradient with our sensitive measure of social position. After adjusting for the effects of smoking rates, alcohol consumption, exercise and dietary pattern, as well as age, ethnicity, body mass index and report of symptoms, the regression coefficient for apo AI on employment grade is reduced by 43% in men and 70% in women. Corresponding reductions for fibrinogen are 53% and 65%. These attenuations suggest that a considerable part of the social gradients in apo AI and fibrinogen are explained by variations in health related behaviours. The remaining gradients may represent effects independent of these behaviours.

Alcohol consumption and sickness absence: from the Whitehall II study

Previous studies suggest that problem drinkers have markedly increased sickness absence. However, it is not clear how more moderate alcohol consumption and abstinence relate to sickness absence. As part of the Whitehall II study the relationship between different drinking patterns and sickness absence is examined. A total of 10,314 male and female civil servants completed a baseline questionnaire about their drinking habits--the amount of alcohol consumed over the past 7 days and the frequency of drinking over the past 12 months. All sickness absence has been recorded prospectively. Drinking patterns and sickness absence are examined for short spells (< or = 7 days) and long spells (> 7 days) adjusting for other causes of sickness absence: age, grade of employment, smoking, work characteristics and baseline health. Alcohol consumption was strongly related to employment grade, the lower the grade the higher proportion of men and women reporting no alcohol consumption. For men the relation of alcohol intake to short spells of sickness absence (< or = 7 days) appeared to be U-shaped, for long spells (> 7 days) increased rates of absence were found only in frequent drinkers. There was no clear relationship for women, however higher rates of sickness absence were found in non-drinkers.

Explaining socioeconomic differences in sickness absence: the Whitehall II Study.

To describe and explain the socioeconomic gradient in sickness absence. Analysis of questionnaire and sickness absence data collected from the first phase of the Whitehall II study. Grade of employment was used as a measure of socioeconomic status. 20 civil service departments in London. 6900 male and 3414 female civil servants aged 35-55 years. Rates of short spells (< or = 7 days) and long spells (> 7 days) of sickness absence. A strong inverse relation between grade of employment and sickness absence was evident. Men in the lowest grade had rates of short and long spells of absence 6.1 (95% confidence interval 5.3 to 6.9) and 6.1 (4.8 to 7.9) times higher than those in the highest grade. For women the corresponding rate ratios were 3.0 (2.3 to 3.9) and 4.2 (2.5 to 6.8) respectively. Several risk factors were identified, including health related behaviours (smoking and frequent alcohol consumption), work characteristics (low levels of control, variety and use of skills, work pace, and support at work), low levels of job satisfaction, and adverse social circumstances outside work (financial difficulties and negative support). These risk factors accounted for about one third of the grade differences in sickness absence. Large grade differences in sickness absence parallel socioeconomic differences in morbidity and mortality found in other studies. Identified risk factors accounted for a small proportion of the grade differences in sickness absence. More accurate measurement of the risk factors may explain some of the remaining differences in sickness absence but other factors, as yet unrecognised, are likely to be important.

The occupational hazard of human immunodeficiency virus and hepatitis B virus infection. II. Effect of grade, age, sex and region of employment on perceived risks and preventive measures adopted by anaesthetists.

The effect of grade, age, sex and region of employment on the attitude of anaesthetists to the possible risk of Human Immunodeficiency Virus (HIV) and Hepatitis B Virus (HBV) infection and the measures adopted to minimise the risk were assessed. As a group, anaesthetists in training were more concerned than consultants about the risk of HIV or HBV infection and, as a consequence, were more likely to adopt protective measures. A similar variation was seen with age, younger anaesthetists being more concerned about the risk of infection and adopting preventive measures in greater numbers than their older colleagues. The sex of the anaesthetist had minimal effect on their attitude. Despite the marked variation in the incidence of both HIV and HBV, the attitude of anaesthetists to the risk of infection and the numbers adopting simple preventive measures did not vary significantly on a regional basis throughout the country. However, there was a significant inter-regional variation in the availability and uptake of HBV immunisation (p < 0.01) and knowledge of the existence of local policy guidelines for the management of known HIV or HBV positive patients (p < 0.01).

Social class and minor psychiatric disorder in British Civil Servants: a validated screening survey using the General Health Questionnaire

Major psychiatric disorder is more common in people of lower rather than higher socioeconomic status. This is less clear for the commoner, so-called minor psychiatric disorders, but these are more affected by tendency to report symptoms. To examine this the distribution of minor psychiatric disorder by employment grade measured by the 30-item General Health Questionnaire is reported from the first cross-sectional phase of the Whitehall II Study of 10,314 London-based civil servants, men and women between 35 and 55 years. Validation of the GHQ in a random subsample stratified by grade and sex (N = 201) suggested that people in lower employment grades tend to under-report minor psychiatric disorder on the GHQ relative to those in higher employment grades. The prevalence of minor psychiatric disorder corrected by the coefficients from the validity study was greater in the lower employment grades than the higher employment grades particularly for men. This was echoed in grade differences in well-being measured by the Affect Balance Scale, and in symptoms and recurrent health problems. Overall, for women there were few clear-cut differences in minor psychiatric disorder by employment grade. The lack of social class gradient in women suggests that further exploration should examine women's role at work and their personal lives for the aetiology of minor psychiatric disorder.