The use of segmented regression in analysing interrupted time series studies : an example in pre-hospital ambulance care

Peer reviewedPublisher PD

Prognostic value of lymph node ratio and extramural vascular invasion on survival for patients undergoing curative colon cancer resection

There was no study funding. We are grateful to Tony Rafferty (Tailored Information for the People of Scotland, TIPs) for providing survival data.Peer reviewedPublisher PD

Generation of Functional CLL-Specific Cord Blood CTL Using CD40-Ligated CLL APC

PMCID: PMC3526610This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Social Class Differences in Secular Trends in Established Coronary Risk Factors over 20 Years: A Cohort Study of British Men from 1978–80 to 1998–2000

Background: Coronary heart disease (CHD) mortality in the UK since the late 1970s has declined more markedly among higher socioeconomic groups. However, little is known about changes in coronary risk factors in different socioeconomic groups. This study examined whether changes in established coronary risk factors in Britain over 20 years between 1978-80 and 1998-2000 differed between socioeconomic groups.Methods and Findings: A socioeconomically representative cohort of 7735 British men aged 40-59 years was followed-up from 1978-80 to 1998-2000; data on blood pressure (BP), cholesterol, body mass index (BMI) and cigarette smoking were collected at both points in 4252 survivors. Social class was based on longest-held occupation in middle-age. Compared with men in non-manual occupations, men in manual occupations experienced a greater increase in BMI (mean difference=0.33 kg/m(2); 95%CI 0.14-0.53; p for interaction=0.001), a smaller decline in non-HDL cholesterol (difference in mean change=0.18 mmol/l; 95%CI 0.11-0.25, p for interaction <= 0.0001) and a smaller increase in HDL cholesterol (difference in mean change=0.04 mmol/l; 95%CI 0.02-0.06, p for interaction <= 0.0001). However, mean systolic BP declined more in manual than non-manual groups (difference in mean change=3.6; 95%CI 2.1-5.1, p for interaction <= 0.0001). The odds of being a current smoker in 1978-80 and 1998-2000 did not differ between non-manual and manual social classes (p for interaction = 0.51).Conclusion: Several key risk factors for CHD and type 2 diabetes showed less favourable changes in men in manual occupations. Continuing priority is needed to improve adverse cardiovascular risk profiles in socially disadvantaged groups in the UK

Transmission of Hepatitis B Core Antibody and Galactomannan Enzyme Immunoassay Positivity via Immunoglobulin Products: A Comprehensive Analysis

BACKGROUND: Therapeutic immunoglobulins are used as replacement or immunomodulatory therapy, but can transmit clinically important molecules. We investigated hepatitis B virus (HBV) antibodies and galactomannan enzyme immunoassay (GM-EIA) positivity. Detection of HBV core antibody may prompt antiviral prophylaxis when commencing therapy such as rituximab; a positive GM-EIA result prompts investigation or treatment for invasive fungal disease. METHODS: We performed a cross-sectional analysis of HBV serology in 80 patients established (>6 months) on immunoglobulin therapy; prospective analysis of HBV serology in 16 patients commencing intravenous immunoglobulin (IVIG); and pre- and post-infusion analysis of GM-EIA in 37 patients receiving IVIG. RESULTS: Pre-IVIG, 9 of 80 patients tested positive for HBV surface antibody and 1 of 80 tested equivocal for HBV core antibody. On IVIG, 79 of 79 tested positive for surface antibody, 37 of 80 tested positive for core antibody, and 10 of 80 tested equivocal for core antibody. There were significant differences by product, but among patients receiving products that appear to transmit core antibody, negative results correlated with lower surface antibody titers and longer time since infusion, suggesting a simple concentration effect. There was a progressive increase with each infusion in the percentage of patients testing positive for HBV core antibody among patients newly commencing IVIG. Some patients “seroreverted” to negative during therapy. Certain IVIG products tested positive for GM-EIA and there were rises in index values in corresponding patient samples from pre- to post-infusion. Overall, 5 of 37 patient samples pre-infusion and 15 of 37 samples post-infusion tested positive for GM-EIA. CONCLUSIONS: HBV antibodies and GM-EIA positivity are common in patients receiving IVIG and confound diagnostic results

The timing of elective caesarean delivery between 2000 and 2009 in England

BACKGROUND: In 2004, the National Institute for Clinical Excellence (NICE) recommended that an elective caesarean section for an uncomplicated pregnancy should not be carried out before 39 completed weeks due to increased risk of respiratory morbidity in newborns. We describe the trends and variation across 63 English NHS trusts in the timing of elective caesarean section (CS) for low-risk singleton deliveries. METHODS: We identified elective CS deliveries between 1st April 2000 and 28th February 2009 in English NHS trusts using the Hospital Episode Statistics. We selected women with uncomplicated pregnancies who had an elective CS delivery after 34 completed weeks of gestation, and analysed the trends and the trust-level variation in the timing of elective CS. The impact of the NICE guidance on the monthly rate of elective CS deliveries performed after 39 weeks was estimated using an interrupted time-series design with autoregressive integrated moving average (ARIMA). RESULTS: There were 118,456 elective CS deliveries at the 63 NHS trusts. The overall proportion of elective CS deliveries done after 39 completed weeks steadily increased from 39% in 2000/01 to 63% in 2008/09. The proportions rose from 43% to 67% for women with breech presentation and from 35% to 62% for women with a previous CS. There was significant variation across NHS trusts in each year; in 2008/09, with the proportions of elective CS done after 39 weeks ranging from 28% to 89% (Inter-quartile range limits: 54% to 72%). We found a small but statistically significant increase in the proportion immediately after the publication of the NICE guidance, but its rate of growth rate declined slightly thereafter. CONCLUSIONS: NHS trusts in our study have responded to the new evidence on the benefits of delaying elective CS to after 39 weeks gestation. However, substantial differences between NHS trusts remain, which indicates there is room for further improvement. We suggest that maternity services and commissioners adopt the "timing of elective caesarean" as a quality indicator to support clinical practice

The Global Health System: Linking Knowledge with Action—Learning from Malaria

In the third in a series of articles on the changing nature of global health institutions, Gerald Keusch and colleagues examine institutional arrangements for malaria research