Paul Elliott

Imperial College London, Londinium, England, United Kingdom

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Publications (452)4351.97 Total impact

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    ABSTRACT: DNA methylation plays a fundamental role in the regulation of the genome, but the optimal strategy for analysis of genome-wide DNA methylation data remains to be determined. We developed a comprehensive analysis pipeline for epigenome-wide association studies (EWAS) using the Illumina Infinium HumanMethylation450 BeadChip, based on 2,687 individuals, with 36 samples measured in duplicate. We propose new approaches to quality control, data normalisation and batch correction through control-probe adjustment and establish a null hypothesis for EWAS using permutation testing. Our analysis pipeline outperforms existing approaches, enabling accurate identification of methylation quantitative trait loci for hypothesis driven follow-up experiments.
    Genome Biology 12/2015; 16(1). DOI:10.1186/s13059-015-0600-x · 10.47 Impact Factor
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    ABSTRACT: This article summarizes current data and approaches to assess sodium intake in individuals and populations. A review of the literature on sodium excretion and intake estimation supports the continued use of 24-h urine collections for assessing population and individual sodium intake. Since 2000, 29 studies used urine biomarkers to estimate population sodium intake, primarily among adults. More than half used 24-h urine; the rest used a spot/casual, overnight, or 12-h specimen. Associations between individual sodium intake and health outcomes were investigated in 13 prospective cohort studies published since 2000. Only three included an indicator of long-term individual sodium intake, i.e., multiple 24-h urine specimens collected several days apart. Although not insurmountable, logistic challenges of 24-h urine collection remain a barrier for research on the relationship of sodium intake and chronic disease. Newer approaches, including modeling based on shorter collections, offer promise for estimating population sodium intake in some groups. Expected final online publication date for the Annual Review of Nutrition Volume 35 is July 17, 2015. Please see for revised estimates.
    Annual Review of Nutrition 05/2015; 35(1). DOI:10.1146/annurev-nutr-071714-034322 · 10.46 Impact Factor
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    Science translational medicine 04/2015; 7(285):285ra62-285ra62. DOI:10.1126/scitranslmed.aaa5680 · 14.41 Impact Factor
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    ABSTRACT: Cathie Sudlow and colleagues describe the UK Biobank, a large population-based prospective study, established to allow investigation of the genetic and non-genetic determinants of the diseases of middle and old age.
    PLoS Medicine 03/2015; 12(3):e1001779. DOI:10.1371/journal.pmed.1001779 · 14.00 Impact Factor
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    ABSTRACT: Adverse blood pressure (BP) is a major independent risk factor for epidemic cardiovascular diseases affecting almost one third of the US adult population. This review synthesizes results from studies published over the past few years on BP differences and prevalent hypertension between US blacks and whites and their different intakes of foods (e.g., fruits, vegetables, and dairy products) and micronutrients (e.g., vitamin D, calcium, potassium, and phosphorus). Studies have consistently reported higher prevalence of adverse BP levels and hypertension and less favorable dietary intakes in blacks than in whites, but the influence of specific dietary factors on high BP risk for blacks remains unclear.
    Current Hypertension Reports 02/2015; 17(2):517. DOI:10.1007/s11906-014-0517-x · 3.90 Impact Factor
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    ABSTRACT: Background—Epidemiologic evidence is sparse on the effect of dietary behaviors and diet quality on body mass index (BMI) that may be important drivers of the obesity epidemic. Objective—This study investigated the relationships of frequency of eating and time of intake to energy density, nutrient quality and BMI using data from the INTERnational study on MAcro/ micronutrients and blood Pressure (INTERMAP) including 2,696 men and women aged 40-59 from the United States and the United Kingdom. Design—INTERMAP is a cross-sectional investigation with four 24-hour dietary recalls and BMI measurements conducted between 1996 and 1999. Consumption of solid foods was aggregated into eating occasion. Nutrient density is expressed using the Nutrient Rich Food (NRF 9.3) index. The ratio of evening/morning energy intake was calculated; mean values of four visits were used. Statistical analyses performed—Characteristics across eating occasion categories are presented as adjusted mean with corresponding 95% confidence interval. Multiple linear regression models were used to examine associations of eating occasions, ratio of evening/ morning energy intake, dietary energy density, and NRF 9.3 index with BMI. Results—Compared to participants with < 4 eating occasions/24-hours, those with ≥ 6 eating occasions/24-hours had lower mean: BMI: 27.3 vs. 29.0 kg/m2; total energy intake: 2,129 vs. 2,472 kcal/24-hours; dietary energy density: 1.5 vs. 2.1 kcal/g; and higher NRF 9.3 index: 34.3 vs. 28.1. In multiple regression analyses, higher evening intake relative to morning intake was directly associated with BMI; however this did not influence the relationship between eating frequency and BMI. Conclusions—Our results suggest that a larger number of small meals may be associated with improved diet quality and lower BMI. This may have implications for behavioral approaches to controlling the obesity epidemic.
    Journal of the American Academy of Nutrition and Dietetics 01/2015; 115(4). DOI:10.1016/j.jand.2014.11.017 · 2.44 Impact Factor
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    ABSTRACT: Increased adiposity is linked with higher risk for cardiometabolic diseases. We aimed to determine to what extent elevated body mass index (BMI) within the normal weight range has causal effects on the detailed systemic metabolite profile in early adulthood. We used Mendelian randomization to estimate causal effects of BMI on 82 metabolic measures in 12,664 adolescents and young adults from four population-based cohorts in Finland (mean age 26 y, range 16-39 y; 51% women; mean ± standard deviation BMI 24±4 kg/m2). Circulating metabolites were quantified by high-throughput nuclear magnetic resonance metabolomics and biochemical assays. In cross-sectional analyses, elevated BMI was adversely associated with cardiometabolic risk markers throughout the systemic metabolite profile, including lipoprotein subclasses, fatty acid composition, amino acids, inflammatory markers, and various hormones (p<0.0005 for 68 measures). Metabolite associations with BMI were generally stronger for men than for women (median 136%, interquartile range 125%-183%). A gene score for predisposition to elevated BMI, composed of 32 established genetic correlates, was used as the instrument to assess causality. Causal effects of elevated BMI closely matched observational estimates (correspondence 87%±3%; R2 = 0.89), suggesting causative influences of adiposity on the levels of numerous metabolites (p<0.0005 for 24 measures), including lipoprotein lipid subclasses and particle size, branched-chain and aromatic amino acids, and inflammation-related glycoprotein acetyls. Causal analyses of certain metabolites and potential sex differences warrant stronger statistical power. Metabolite changes associated with change in BMI during 6 y of follow-up were examined for 1,488 individuals. Change in BMI was accompanied by widespread metabolite changes, which had an association pattern similar to that of the cross-sectional observations, yet with greater metabolic effects (correspondence 160%±2%; R2 = 0.92). Mendelian randomization indicates causal adverse effects of increased adiposity with multiple cardiometabolic risk markers across the metabolite profile in adolescents and young adults within the non-obese weight range. Consistent with the causal influences of adiposity, weight changes were paralleled by extensive metabolic changes, suggesting a broadly modifiable systemic metabolite profile in early adulthood. Please see later in the article for the Editors' Summary.
    PLoS Medicine 12/2014; 11(12):e1001765. DOI:10.1371/journal.pmed.1001765 · 14.00 Impact Factor
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    ABSTRACT: Observational studies have suggested that the risks of non-communicable diseases in voluntary migrants become similar to those in the host population after one or more generations, supporting the hypothesis that these diseases have a predominantly environmental (rather than inherited) origin. However, no study has been conducted thus far to identify alterations at the molecular level that might mediate these changes in disease risk after migration.
    International Journal of Epidemiology 10/2014; DOI:10.1093/ije/dyu198 · 9.20 Impact Factor
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    ABSTRACT: Background The Airwave Health Monitoring Study was established to evaluate possible health risks associated with use of TETRA, a digital communication system used by police forces and other emergency services in Great Britain since 2001. The study has been broadened to investigate more generally the health of the work force. Methods From 2004, participants from each force who agreed to participate were enrolled either with an enrolment questionnaire or a comprehensive health screening performed locally. This includes questionnaire, 7-day food diaries, anthropometry, measurements of cardiovascular and cognitive function, blood chemistry, coagulation and haematology. Blood and urine samples are stored in vapour phase liquid nitrogen allowing long-term access for biochemical or genetic analysis. Access to the resource is via an access committee and a steering committee, including external scientific advisers as well as representatives of the police officers and staff. Results By the end of 2012, the study had recruited 42,112 participants, of whom 35,199 (83.6%) had attended the health screening. Almost two thirds of participants were men and 71% of them were a TETRA user. Being in lower ranks (constable/sergeant and staff) was associated with a worse cardio-metabolic risk profile compared to higher ranks (inspector or chief inspector, superintendent and above). Conclusion The Airwave Health Monitoring Study is the only large-scale cohort study of police employees worldwide. The specificities of this sample, such as its well-defined job hierarchy, make it a particularly valuable occupational cohort. Participants have consented to the use of their data and samples for future, currently unspecified, research purposes.
    Environmental Research 10/2014; 134:280–285. DOI:10.1016/j.envres.2014.07.025 · 3.95 Impact Factor
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    ABSTRACT: The Dietary Approaches to Stop Hypertension-Sodium (DASH-Sodium) trial demonstrated beneficial effects on blood pressure (BP) of the DASH diet with lower sodium intake when compared with typical American diet. The subsequent Optimal Macronutrient Intake Trial for Heart Health (OMNIHEART) trial reported additional BP benefits from replacing carbohydrate in the DASH diet with either protein or monounsaturated fats. The primary aim of this study is to assess possible BP benefits of an OMNIHEART-like diet in free-living Americans using cross-sectional US population data of The International Study of Macronutrients, Micronutrients and Blood Pressure (INTERMAP) study. The INTERMAP data include four 24-hour dietary recalls, 2 timed 24-hour urine collections, 8 BP readings for 2195 individuals aged 40 to 59 years from 8 US INTERMAP population samples. Analyses are conducted using 2 approaches: (1) regression of BP on a linear OMNIHEART nutrient score calculated for each individual and (2) a Bayesian approach comparing estimated BP levels of an OMNIHEART-like nutrient profile with a typical American nutrient profile. After adjustment for potential confounders, an OMNIHEART score higher by 1 point was associated with systolic/diastolic BP differences of -1.0/-0.5 mm Hg (both P<0.001). Mean systolic/diastolic BPs were 111.3/68.4 and 115.2/70.6 mm Hg for Bayesian OMNIHEART and Control profiles, respectively, after controlling for possible confounders, with BP differences of -3.9/-2.2 mm Hg, P(difference ≤0)=0.98/0.96. Findings were comparable for men and women, for nonhypertensive participants, and with adjustment for antihypertensive treatment. Our findings from data on US population samples indicate broad generalizability of OMNIHEART results beyond the trial setting and support recommendations for an OMNIHEART-style diet for prevention/control of population-wide adverse BP levels.
    Hypertension 09/2014; 64(6). DOI:10.1161/HYPERTENSIONAHA.114.03799 · 7.63 Impact Factor
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    ABSTRACT: Objective: Habitual high-salt intake raises blood pressure and risk of cardiovascular diseases. To prevent/control these risks, reduced salt diet (RSD) is recommended in many countries and some people report practicing it; however, little is known about actual achievement. This population-based study assessed level of 24-h dietary sodium intake of participants reporting RSD and others. Method: Participants were 4680 men and women ages 40-59 years randomly selected from 17 populations in People's Republic of China (PRC), Japan, UK and USA, for an observational study on diet and blood pressure (INTERMAP). Daily sodium intake was determined by two timed 24-h urine collections. Antihypertensive treatment status and RSD were ascertained by questionnaire. Results: Participants reporting RSD were few; 3.1% (Japan), 1.3% (PRC), 2.5% (UK), 7.2% (USA); 15.1, 7.9, 16.7 and 16.8% of people with treated hypertension. For those reporting RSD, 24-h urinary sodium excretion was significantly, but only modestly lower than for others, by 17.9 mmol/day (Japan), 56.7 (PRC) and 14.7 (USA), but higher by 10.5 in UK. Sodium intakes for participants reporting RSD remained higher than recommended; 181.0 mmol/day (Japan), 171.5 (PRC), 155.2 (UK) and 148.9 (USA). For these people, as for others, main sources of salt were processed foods in Japan, UK and USA; in PRC, salt added in preparation at home. Conclusion: Enhanced sustained efforts are needed to raise general awareness of the harmful effects of salt on health and the benefits of salt reduction. Population approaches are needed to reduce salt content of processed foods and restaurant meals.
    Journal of Hypertension 09/2014; 32(12). DOI:10.1097/HJH.0000000000000341 · 4.22 Impact Factor
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    ABSTRACT: The genetic sequence variation of people from the Indian subcontinent who comprise one-quarter of the world's population, is not well described. We carried out whole genome sequencing of 168 South Asians, along with whole-exome sequencing of 147 South Asians to provide deeper characterisation of coding regions. We identify 12,962,155 autosomal sequence variants, including 2,946,861 new SNPs and 312,738 novel indels. This catalogue of SNPs and indels amongst South Asians provides the first comprehensive map of genetic variation in this major human population, and reveals evidence for selective pressures on genes involved in skin biology, metabolism, infection and immunity. Our results will accelerate the search for the genetic variants underlying susceptibility to disorders such as type-2 diabetes and cardiovascular disease which are highly prevalent amongst South Asians.
    PLoS ONE 08/2014; 9(8):e102645. DOI:10.1371/journal.pone.0102645 · 3.53 Impact Factor
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    ABSTRACT: Fetal and postnatal growth have been associated with adult blood pressure (BP), but findings about the relative importance of growth at different stages of life on BP are inconsistent.
    Journal of Epidemiology &amp Community Health 08/2014; DOI:10.1136/jech-2013-203661 · 3.29 Impact Factor
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    ABSTRACT: BACKGROUND: High blood pressure, blood glucose, serum cholesterol, and BMI are risk factors for cardiovascular diseases and some of these factors also increase the risk of chronic kidney disease and diabetes. We estimated mortality from cardiovascular diseases, chronic kidney disease, and diabetes that was attributable to these four cardiometabolic risk factors for all countries and regions from 1980 to 2010. METHODS: We used data for exposure to risk factors by country, age group, and sex from pooled analyses of population-based health surveys. We obtained relative risks for the effects of risk factors on cause-specific mortality from meta-analyses of large prospective studies. We calculated the population attributable fractions for each risk factor alone, and for the combination of all risk factors, accounting for multicausality and for mediation of the effects of BMI by the other three risks. We calculated attributable deaths by multiplying the cause-specific population attributable fractions by the number of disease-specific deaths. We obtained cause-specific mortality from the Global Burden of Diseases, Injuries, and Risk Factors 2010 Study. We propagated the uncertainties of all the inputs to the final estimates. FINDINGS: In 2010, high blood pressure was the leading risk factor for deaths due to cardiovascular diseases, chronic kidney disease, and diabetes in every region, causing more than 40% of worldwide deaths from these diseases; high BMI and glucose were each responsible for about 15% of deaths, and high cholesterol for more than 10%. After accounting for multicausality, 63% (10·8 million deaths, 95% CI 10·1-11·5) of deaths from these diseases in 2010 were attributable to the combined effect of these four metabolic risk factors, compared with 67% (7·1 million deaths, 6·6-7·6) in 1980. The mortality burden of high BMI and glucose nearly doubled from 1980 to 2010. At the country level, age-standardised death rates from these diseases attributable to the combined effects of these four risk factors surpassed 925 deaths per 100 000 for men in Belarus, Kazakhstan, and Mongolia, but were less than 130 deaths per 100 000 for women and less than 200 for men in some high-income countries including Australia, Canada, France, Japan, the Netherlands, Singapore, South Korea, and Spain. INTERPRETATION: The salient features of the cardiometabolic disease and risk factor epidemic at the beginning of the 21st century are high blood pressure and an increasing effect of obesity and diabetes. The mortality burden of cardiometabolic risk factors has shifted from high-income to low-income and middle-income countries. Lowering cardiometabolic risks through dietary, behavioural, and pharmacological interventions should be a part of the global response to non-communicable diseases.
    The Lancet Diabetes & Endocrinology 08/2014; 2(8):634-47. DOI:10.1016/S2213-8587(14)70102-0 · 9.19 Impact Factor
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    ABSTRACT: Metabolomics is the field of "-omics" research concerned with the comprehensive characterization of the small low-molecular-weight metabolites in biological samples. In epidemiology, it represents an emerging technology and an unprecedented opportunity to measure environmental and other exposures with improved precision and far less measurement error than with standard epidemiologic methods. Advances in the application of metabolomics in large-scale epidemiologic research are now being realized through a combination of improved sample preparation and handling, automated laboratory and processing methods, and reduction in costs. The number of epidemiologic studies that use metabolic profiling is still limited, but it is fast gaining popularity in this area. In the present article, we present a roadmap for metabolomic analyses in epidemiologic studies and discuss the various challenges these data pose to large-scale studies. We discuss the steps of data preprocessing, univariate and multivariate data analysis, correction for multiplicity of comparisons with correlated data, and finally the steps of cross-validation and external validation. As data from metabolomic studies accumulate in epidemiology, there is a need for large-scale replication and synthesis of findings, increased availability of raw data, and a focus on good study design, all of which will highlight the potential clinical impact of metabolomics in this field.
    American Journal of Epidemiology 06/2014; 180(2). DOI:10.1093/aje/kwu143 · 4.98 Impact Factor
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    ABSTRACT: National mortality statistics report that UK Indian Asians are at approxiamately 2 fold higher risk of cardiovascular disease mortality compared with people of European ancestry. However, previous studies in North American and European populations suggest that up to 40% of death certificates are incorrect, leading to an overestimation of cardiovascular disease mortality. The validity of routine death certification amongst Indian Asians is unknown.
    Heart (British Cardiac Society) 06/2014; 100(Suppl 3):A64. DOI:10.1136/heartjnl-2014-306118.111 · 6.02 Impact Factor
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    ABSTRACT: Public concern about potential health risks associated with incineration has prompted studies to investigate the relationship between incineration and risk of cancer, and more recently, birth outcomes. We conducted a systematic review of epidemiologic studies evaluating the relationship between waste incineration and the risk of adverse birth and neonatal outcomes. Literature searches were performed within the MEDLINE database, through PubMed and Ovid interfaces, for the search terms; incineration, birth, reproduction, neonatal, congenital anomalies and all related terms. Here we discuss and critically evaluate the findings of these studies. A comprehensive literature search yielded fourteen studies, encompassing a range of outcomes (including congenital anomalies, birth weight, twinning, stillbirths, sex ratio and infant death), exposure assessment methods and study designs. For congenital anomalies most studies reported no association with proximity to or emissions from waste incinerators and "all anomalies", but weak associations for neural tube and heart defects and stronger associations with facial clefts and urinary tract defects. There is limited evidence for an association between incineration and twinning and no evidence of an association with birth weight, stillbirths or sex ratio, but this may reflect the sparsity of studies exploring these outcomes. The current evidence-base is inconclusive and often limited by problems of exposure assessment, possible residual confounding, lack of statistical power with variability in study design and outcomes. However, we identified a number of higher quality studies reporting significant positive relationships with broad groups of congenital anomalies, warranting further investigation. Future studies should address the identified limitations in order to help improve our understanding of any potential adverse birth outcomes associated with incineration, particularly focussing on broad groups of anomalies, to inform risk assessment and waste policy.
    Environment international 05/2014; 69C:120-132. DOI:10.1016/j.envint.2014.04.003 · 5.66 Impact Factor
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    ABSTRACT: Evidence from animal models suggests that locomotion and blood pressure share common neurophysiological regulatory systems. As a result of this common regulation, we hypothesized that the development of locomotion in human infants would be associated with blood pressure levels in adulthood. The study sample comprised 4,347 individuals with measures of locomotive and non-locomotive neuromotor development in infancy and adult blood pressure levels within a longitudinal birth cohort study, the Northern Finland Birth Cohort 1966. Later development in all three stages of locomotive development during infancy was associated with higher systolic and diastolic blood pressure levels at age 31. For age of walking without support, 0.34 (95 % CI 0.07 to 0.60)-mm Hg higher SBP and 0.38 (95 % CI 0.15 to 0.62)-mm Hg higher DBP were estimated for each month of later achievement (P = 0.012 for SBP; P = 0.001 for DBP). No association was identified for non-locomotive neuromotor development. Conclusion: These results highlight the positive sequelae of advanced locomotive development during infancy, suggesting that the common regulatory systems between locomotion and blood pressure may influence the development of raised blood pressure over time.
    European Journal of Pediatrics 05/2014; 173(10). DOI:10.1007/s00431-014-2326-2 · 1.98 Impact Factor
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    ABSTRACT: Little is known about genes regulating male puberty. Further, while many identified pubertal timing variants associate with age at menarche, a late manifestation of puberty, and body mass, little is known about these variants' relationship to pubertal initiation or tempo. To address these questions, we performed genome-wide association meta-analysis in over 11,000 European samples with data on early pubertal traits, male genital and female breast development, measured by the Tanner scale. We report the first genome-wide significant locus for male sexual development upstream of MKL2 (P=8.9 x 10(-9)), a menarche locus tagging a developmental pathway linking earlier puberty with reduced pubertal growth (P=4.6 x 10(-5)) and short adult stature (P=1.1 x 10(-11)) in both males and females. Furthermore, our results indicate that a proportion of menarche loci are important for pubertal initiation in both sexes.Consistent with epidemiological correlations between increased prepubertal body mass and earlier pubertal timing in girls, BMI-increasing alleles correlated with earlier breast development. In boys, some BMI-increasing alleles associated with earlier, and others with delayed, sexual development; these genetic results mimic the controversy in epidemiological studies, some of which show opposing correlations between prepubertal BMI and male puberty. Our results contribute to our understanding of the pubertal initiation program in both sexes, and indicate that although mechanisms regulating pubertal onset in males and females may largely be shared, the relationship between body mass and pubertal timing in boys may be complex and requires further genetic studies.
    Human Molecular Genetics 04/2014; DOI:10.1093/hmg/ddu150 · 6.68 Impact Factor
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    ABSTRACT: Warm temperatures adversely affect disease occurrence and death, in extreme conditions as well as when the temperature changes are more modest. Therefore climate change, which is expected to affect both average temperatures and temperature variability, is likely to impact health even in temperate climates. Climate change risk assessment is enriched if there is information on vulnerability and resilience to effects of temperature. Some studies have analysed socio-demographic characteristics that make individuals vulnerable to adverse effects of temperature. Less is known about community-level vulnerability. We used geo-coded mortality and environmental data and Bayesian spatial methods to conduct a national small-area analysis of the mortality effects of warm temperature for all 376 districts in England and Wales. In the most vulnerable districts, those in London and south/southeast England, odds of dying from cardiorespiratory causes increased by more than 10% for 1 °C warmer temperature, compared with virtually no effect in the most resilient districts, which were in the far north. A 2 °C warmer summer may result in 1,552 (95% credible interval 1,307-1,762) additional deaths, about one-half of which would occur in 95 districts. The findings enable risk and adaptation analyses to incorporate local vulnerability to warm temperature and to quantify inequality in its effects.
    Nature Climate Change 03/2014; DOI:10.1038/NCLIMATE2123 · 15.30 Impact Factor

Publication Stats

26k Citations
4,351.97 Total Impact Points


  • 1997–2015
    • Imperial College London
      • • Department of Epidemiology and Biostatistics
      • • School of Public Health
      • • Faculty of Medicine
      Londinium, England, United Kingdom
  • 2013
    • Uppsala University
      Uppsala, Uppsala, Sweden
    • Harvard Medical School
      • Department of Medicine
      Boston, Massachusetts, United States
  • 2012
    • University of Gothenburg
      • Department of Molecular and Clinical Medicine
      Göteborg, Vaestra Goetaland, Sweden
    • McGill University
      • Department of Epidemiology, Biostatistics and Occupational Health
      Montréal, Quebec, Canada
    • University of Groningen
      Groningen, Groningen, Netherlands
    • Wake Forest School of Medicine
      Winston-Salem, North Carolina, United States
  • 2011
    • University Hospital of Lausanne
      Lausanne, Vaud, Switzerland
  • 2010–2011
    • Imperial Valley College
      Imperial, California, United States
    • University of Exeter
      • Peninsula College of Medicine and Dentistry
      Exeter, ENG, United Kingdom
    • Shiga University of Medical Science
      • Department of Health Science
      Ōtu, Shiga, Japan
  • 2004–2010
    • University of Oulu
      • • Institute of Health Sciences
      • • Department of Public Health Science and General Practice
      Oulu, Oulu, Finland
  • 2009
    • CREAL Center for Research in Environmental Epidemiology
      Barcino, Catalonia, Spain
  • 2008
    • University of Leicester
      • Department of Health Sciences
      Leicester, ENG, United Kingdom
  • 2007
    • University of Oxford
      • Nuffield Department of Obstetrics and Gynaecology
      Oxford, England, United Kingdom
    • University of Greenwich
      • Department of Mathematical Sciences
      Londinium, England, United Kingdom
  • 2006
    • University of Bath
      Bath, England, United Kingdom
    • UK Department of Health
      Londinium, England, United Kingdom
    • Johns Hopkins University
      Baltimore, Maryland, United States
  • 1995–2006
    • Northwestern University
      • Department of Preventive Medicine
      Evanston, Illinois, United States
  • 2005
    • King's College London
      • Department of Nutrition and Dietetics
      London, ENG, United Kingdom
  • 2001
    • The University of Edinburgh
      • School of Clinical Sciences and Community Health
      Edinburgh, Scotland, United Kingdom
  • 2000–2001
    • University College London
      • Department of Epidemiology and Public Health
      London, ENG, United Kingdom
  • 1998–1999
    • Imperial College Healthcare NHS Trust
      Londinium, England, United Kingdom
  • 1996
    • National Heart, Lung, and Blood Institute
      Maryland, United States
    • Group Health Cooperative
      Seattle, Washington, United States
    • Lancaster University
      • Department of Mathematics and Statistics
      Lancaster, ENG, United Kingdom
    • University of Leuven
      Louvain, Flanders, Belgium
  • 1989–1996
    • London School of Hygiene and Tropical Medicine
      • Faculty of Epidemiology and Population Health
      Londinium, England, United Kingdom
  • 1994
    • Hospital of Saint Raphael
      New Haven, Connecticut, United States