Paul Clarke

Employment status, employment conditions, and limiting illness: prospective evidence from the British household panel survey 1991–2001

Objectives: To assess the relation of the incidence of, and recovery from, limiting illness to employment status, occupational social class, and income over time in an initially healthy sample of working age men and women. Methods: Cox proportional hazards models. Results: There were large differences in the risk of limiting illness according to occupational social class, with men and women in the least favourable employment conditions nearly four times more likely to become ill than those in the most favourable. Unemployment and economic inactivity also had a powerful effect on illness incidence. Limiting illness was not a permanent state for most participants in the study. Employment status was also related to recovery. Conclusions: Having secure employment in favourable working conditions greatly reduces the risk of healthy people developing limiting illness. Secure employment increases the likelihood of recovery. These findings have considerable implications for both health inequality and economic policies.

Social dynamics of health inequalities: a growth curve analysis of aging and self assessed health in the British household panel survey 1991–2001

Objectives: To study how social inequalities change as people age, this paper presents a growth curve model of self assessed health, which accommodates changes in occupational class and individual health with age. Design: Nationally representative interview based longitudinal survey of adults in Great Britain. Setting: Representative members of private households of Great Britain in 1991. Participants: Survey respondents (n = 6705), aged 21–59 years in 1991 and followed up annually until 2001. Main outcome measure: Self assessed health. Results: On average, self assessed health declines slowly from early adulthood to retirement age. No significant class differences in health were observed at age 21. Health inequalities emerged later in life with the gap between mean levels of self assessed health of those in managerial and professional occupations and routine occupations widening approaching retirement. Individual variability in health trajectories increased between ages 40 and 59 years so that this widening of mean differences between occupational classes was not significant. When the analysis is confined to people whose occupational class remained constant over time, a far greater difference in health trajectories between occupational classes was seen. Conclusions: The understanding of social inequalities in health at the population level is enriched by an analysis of individual variation in age related declines by social position.

The Transmissibility of Highly Pathogenic Avian Influenza in Commercial Poultry in Industrialised Countries

Background With the increased occurrence of outbreaks of H5N1 worldwide there is concern that the virus could enter commercial poultry farms with severe economic consequences. Methodology/Principal Findings We analyse data from four recent outbreaks of highly pathogenic avian influenza (HPAI) in commercial poultry to estimate the farm-to-farm reproductive number for HPAI. The reproductive number is a key measure of the transmissibility of HPAI at the farm level because it can be used to evaluate the effectiveness of the control measures. In these outbreaks the mean farm-to-farm reproductive number prior to controls ranged from 1.1 to 2.4, with the maximum farm-based reproductive number in the range 2.2 to 3.2. Enhanced bio-security, movement restrictions and prompt isolation of the infected farms in all four outbreaks substantially reduced the reproductive number, but it remained close to the threshold value 1 necessary to ensure the disease will be eradicated. Conclusions/Significance Our results show that depending on the particular situation in which an outbreak of avian influenza occurs, current controls might not be enough to eradicate the disease, and therefore a close monitoring of the outbreak is required. The method we used for estimating the reproductive number is straightforward to implement and can be used in real-time. It therefore can be a useful tool to inform policy decisions.

Who you live with and where you live: setting the context for health using multiple membership multilevel models

Study objective: Previous studies into the effect of area of residence on individuals’ health have not accounted for changing residency over time, although few people remain resident in the same area throughout their life. Furthermore, few studies of area effects on health have accounted for the clustering of health at the household level. These methodological problems may have led previous studies to under estimate or over estimate the size of area level effects. This study uses multiple membership multilevel models to investigate whether longitudinal analyses of area effects on health need to take account of clustering at the household level. Setting and participants: A longitudinal survey (1991–1999) of a nationally representative sample of British households (5511 households with 10 264 adult members). Design: Two level (individuals within households or areas) and three level (individuals within households within areas) multiple membership models of SF-36 physical and mental health functioning scores at wave nine were analysed adjusting for age, gender, education, marital, employment, and smoking status from previous waves. Results: Physical and mental health functioning seem to cluster within households. Accounting for changes in household membership over time increases estimates of the clustering in functioning at the household level. The clustering of functioning within area wards is reduced when the clustering within households and risk factors for functioning are taken into account. Conclusions: Clustered sampling units within study designs should be taken account of in individual level analyses. Changes in these units over time should be accounted for in longitudinal analysis.

Is there the potential for an epidemic of variant Creutzfeldt-Jakob disease via blood transfusion in the UK?

The discovery of three individuals suspected to have contracted variant Creutzfeldt–Jakob disease (vCJD) through blood transfusions has heightened concerns that a secondary epidemic via human-to-human transmission could occur in the UK. The Department of Health responded immediately to this threat by banning those who had received blood transfusions since 1980 from donating blood. In this paper, we conduct a sensitivity analysis to explore the potential size of a blood-borne vCJD epidemic and investigate the effectiveness of public health interventions. A mathematical model was developed together with an expression for the basic reproduction number (R0). The sensitivity of model predictions to unknown parameters determining the transmission of vCJD via infected blood was assessed under pessimistic modelling assumptions. We found that the size of the epidemic (up until 2080) was bounded above by 900 cases, with self-sustaining epidemics (R0>1) also possible; but the scenarios under which such epidemics could arise were found to be biologically implausible. Under optimistic assumptions, public health interventions reduced the upper bound to 250 and further still when only biologically plausible scenarios were considered. Our results support the belief that scenarios leading to large or self-sustaining epidemics are possible but unlikely, and that public health interventions were effective.

Changes in British men's use of family planning services between 1991 and 2000: secondary analysis of a national survey.

Background and methodology Although men are identified as a priority group for sexual health initiatives, limitations in other data sources mean little is known about their use of general practitioners (GPs) or family planning clinics (FPCs) for family planning services. This paper provides a unique profile of which men have increased their use of GPs or FPCs for family planning services over the 1990s. Data were taken from the repeated cross-sectional British Omnibus Survey, 1991–2000. In total, 16 470 men aged 16–49 years were asked which health service they had used for family planning purposes within the last 5 years. Results Although around two-thirds of men cite general practice as their preferred source for professional advice on contraception, in 2000 only 12.5% (95% CI 11–14) had used this source for family planning purposes in the past 5 years. Between 1991 and 2000, the greatest growth was in use of FPCs, particularly among men aged 16–24 years, of single or cohabiting marital status, or of professional or unskilled social class. The greatest growth in use of GPs relative to use in 1991 was among men aged 35–44 years and those in the skilled non-manual and skilled manual social classes. Discussion and conclusions As the 1990s progressed, an increasing percentage of men attended GPs and FPCs for family planning purposes. Differential rates of growth by age group, marital status and social class have occurred, but levels of use are still much lower than for women.From 2004 to 2006 CEDPA joined with local partners in the Baglung Mohottari and Udayapur districts of Nepal to improve adolescent girls lives through a non-formal education program. The program reached 3200 adolescents between the ages of 10-19 with literacy and critical life skills training that improved participants reproductive health knowledge and strengthened their self-confidence. Recognizing the need to work with boys as well as girls to change community norms school-aged boys were included in year two of the program. CEDPA and its partners-Aamaa Milan Kendra Nepal Technical Assistance Group and the Nepal Red Cross Society-also addressed family and community factors to provide support for changes in attitudes and behaviors. An impressive 45 percent of the out-of-school girls who completed the literacy training component enrolled in primary schools as a result of the project. (excerpt)