Christopher Bartlett
University of Bristol
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Christopher Bartlett.
BMJ | 2002
Lee Hooper; Christopher Bartlett; George Davey Smith; Shah Ebrahim
Abstract Objective: To assess the long term effects of advice to restrict dietary sodium in adults with and without hypertension. Design: Systematic review and meta-analysis of randomised controlled trials. Data sources: Cochrane library, Medline, Embase, and bibliographies. Study selection: Unconfounded randomised trials that aimed to reduce sodium intake in healthy adults over at least 6 months. Inclusion decisions, validity and data extraction were duplicated. Random effects meta-analysis, subgrouping, sensitivity analysis, and meta-regression were performed. Outcomes: Mortality, cardiovascular events, blood pressure, urinary sodium excretion, quality of life, and use of antihypertensive drugs. Results: Three trials in normotensive people (n=2326), five trials in those with untreated hypertension (n=387), and three trials in people being treated for hypertension (n=801) were included, with follow up from six months to seven years. The large high quality (and therefore most informative) studies used intensive behavioural interventions. Deaths and cardiovascular events were inconsistently defined and reported. There were 17 deaths, equally distributed between intervention and control groups. Systolic and diastolic blood pressures were reduced (systolic by 1.1 mm Hg, 95% confidence interval 1.8 to 0.4 mm Hg; diastolic by 0.6 mm Hg, 1.5 to 0.3 mm Hg) at 13 to 60 months, as was urinary 24 hour sodium excretion (by 35.5 mmol/24 hours, 47.2 to 23.9). Degree of reduction in sodium intake and change in blood pressure were not related. Conclusions: Intensive interventions, unsuited to primary care or population prevention programmes, provide only small reductions in blood pressure and sodium excretion, and effects on deaths and cardiovascular events are unclear. Advice to reduce sodium intake may help people on antihypertensive drugs to stop their medication while maintaining good blood pressure control.
BMJ | 2002
Christopher Bartlett; Jonathan A C Sterne; Matthias Egger
Abstract Objective: To assess the characteristics of medical research that is press released by general medical journals and reported in newspapers. Design: Longitudinal study. Data sources: All original research articles published in Lancet and BMJ during 1999 and 2000. Main outcome measures: Inclusion of articles in Lancet or BMJ press releases, and reporting of articles in Times or Sun newspapers. Results: Of 1193 original research articles, 517 (43%) were highlighted in a press release and 81 (7%) were reported in one or both newspapers. All articles covered in newspapers had been press released. The probability of inclusion in press releases was similar for observational studies and randomised controlled trials, but trials were less likely to be covered in the newspapers (odds ratio 0.15 (95% confidence interval 0.06 to 0.37)). Good news and bad news were equally likely to be press released, but bad news was more likely to be reported in newspapers (1.74 (1.07 to 2.83)). Studies of womens health, reproduction, and cancer were more likely to be press released and covered in newspapers. Studies from industrialised countries other than Britain were less likely to be reported in newspapers (0.51 (0.31 to 0.82)), and no studies from developing countries were covered. Conclusions: Characteristics of articles were more strongly associated with selection for reporting in newspapers than with selection for inclusion in press releases, although each stage influenced the reporting process. Newspapers underreported randomised trials, emphasised bad news from observational studies, and ignored research from developing countries. What is already known on this topic Newspapers are an important source of information about the results of medical research There are two stages on the path to newspaper coverage—selection by medical journal editors of articles to be press released and the selection of newsworthy articles by journalists What this study adds Examination of press releasing by the Lancet and BMJ and reporting by the Times and Sun showed that selection processes acted at both stages The net effect meant that newspapers emphasised results from observational studies, in particular studies of womens health, reproduction, and cancer Good news and bad news were equally likely to be press released, but bad news was more likely to be reported in newspaper articles
BMJ | 2005
Li Wei; Shah Ebrahim; Christopher Bartlett; Peter D Davey; Frank Sullivan; Thomas M. MacDonald
Abstract Objective To compare the social and demographic profiles of patients who receive statin treatment after myocardial infarction and patients included in randomised trials. To estimate the effect of statin use in community based patients on subsequent all cause mortality and cardiovascular recurrence, contrasting effects with trial patients. Design Observational cohort study using a record linkage database. Setting Tayside, Scotland (population size and characteristics: about 400 000, mixed urban and rural). Subjects 4892 patients were discharged from hospital after their first myocardial infarction between January 1993 and December 2001. 2463 (50.3%) were taking statins during an average follow-up of 3.7 years (3.1% in 1993 and 62.9% in 2001). Main outcome measures All cause mortality and recurrence of cardiovascular events. Results 319 deaths occurred in the statin treated group (age adjusted rate 4.1 per 100 person years, 95% confidence interval 3.2 to 4.9), and 1200 in the statin untreated group (12.7 per 100 person years, 11.1 to 14.3). More older people and women were represented in the population of patients treated with statins than among those recruited into clinical trials (mean age 67.8 v 59.8; women 39.6% v 16.9%, respectively). The effects of statins in routine clinical practice were consistent with, and similar to, those reported in clinical trials (adjusted hazard ratio for all cause mortality 0.69, 95% confidence interval 0.59 to 0.80; adjusted hazard ratio for cardiovascular recurrence 0.82, 0.71 to 0.95). Conclusions The community effectiveness of statins in those groups that were not well represented in clinical trials was similar to the efficacy of statins in these trials.
BMJ | 2004
Paul Dieppe; Christopher Bartlett; Peter Davey; Lesley Doyal; Shah Ebrahim
To provide safe and effective interventions for people, reliable and valid evidence is needed. This is most easily produced by undertaking trials in samples of people who are as homogeneous as possible and applying the results to similar, well defined groups of patients. To be equitable, however, appropriate care needs to be provided for everyone in the diverse community using health services. Therefore, there is a tension between obtaining scientific evidence that is reliable but which can be applied only to a small subset of the population, and distributive justice that requires that all in need are treated equally appropriately. Drugs have potential harms as well as benefits. Doctors would like to be able to balance any risks against benefits to derive a therapeutic ratio for each patient, but this is difficult. Formal trials can tell a lot about the efficacy of a drug in a specific context, but unless they are huge and pragmatic they tell less about a drugs toxicity. Post-marketing surveillance may uncover more information on toxicity, but the data usually lack sufficient detail to lead to an understanding of the determinants of adverse reactions. Furthermore, extrapolation of the efficacy or toxicity of a drug in one disease or group of patients to those associated with different diseases or groups can be difficult and misleading. We examined aspects of these problems in the context of one commonly prescribed class of drugs—non-selective, non-steroidal anti-inflammatory agents (NSAIDs)—and their use in the management of joint pain. We compared the types of patients in whom trials of non-selective NSAIDs are conducted with those who receive the drugs in practice. Then we examined the prevalence and associations of adverse events in these two groups. ### Methods As NSAIDs are primarily used to treat arthritic pain, we studied trials of these drugs in patients with …
Huisarts En Wetenschap | 2003
Lee Hooper; Christopher Bartlett; G Davey Smith; S Ebrahim
SamenvattingAchtergrond en uitkomstmaten De zoutbloeddruktheorie is al jaren onderwerp van discussie. Deze twee Cochranereviews onderzochten of natriumbeperking via bloeddrukverlaging wel leidt tot een afname van cardiovasculaire ziekten en dood. Hooper et al. keken naar het langetermijneffect (ten minste zes maanden) van zoutbeperking. Als primaire uitkomstmaten golden: fataal en niet-fataal myocardinfarct, CVA, angina pectoris, hartfalen, perifeer vasculair lijden, plotse dood en niet-geplande invasieve cardiovasculaire diagnostiek of therapie. Secundaire uitkomstmaten waren: veranderingen in de bloeddruk, kwaliteit van leven, lichaamsgewicht, nutriënteninneming, 24-uurs urine natriumuitscheiding en het kwantitatieve en kwalitatieve gebruik van antihypertensiva.
Journal of Mental Health | 2001
Christopher Bartlett; John W. Holloway; Mark Evans; John Owen; Glynn Harrison
Acute psychiatric beds in the UK are under pressure. More beds are often called for, yet conceivably many in-patients might benefit from alternative care-settings. We studied an admissions cohort of 730 cases in four hospitals over a 5-month period. Using a structured instrument, Consultant Psychiatrists recorded an opinion, on a case-by-case basis, stating whether admission was divertible or whether discharge was delayed, recommending alternative placements where applicable. One hundred and seventy-nine of 543 cases with stays completed in the study period were deemed inappropriately placed at some point (33.0%, 95% CI 29.0 to 36.9), with 112 (21%) being divertible admissions. When surveyed systematically, clinicians reported that many in-patients could benefit from alternative caresettings, the majority being community-based services, although more specialised hospital beds were also needed. Divertible admissions are judged to impose more pressure on acute beds than delayed discharges, although a small ...Acute psychiatric beds in the UK are under pressure. More beds are often called for, yet conceivably many in-patients might benefit from alternative care-settings. We studied an admissions cohort of 730 cases in four hospitals over a 5-month period. Using a structured instrument, Consultant Psychiatrists recorded an opinion, on a case-by-case basis, stating whether admission was divertible or whether discharge was delayed, recommending alternative placements where applicable. One hundred and seventy-nine of 543 cases with stays completed in the study period were deemed inappropriately placed at some point (33.0%, 95% CI 29.0 to 36.9), with 112 (21%) being divertible admissions. When surveyed systematically, clinicians reported that many in-patients could benefit from alternative caresettings, the majority being community-based services, although more specialised hospital beds were also needed. Divertible admissions are judged to impose more pressure on acute beds than delayed discharges, although a small number of difficult-to-place patients with protracted stays can occupy many bed-days.
Health Technology Assessment | 2003
Matthias Egger; Peter Jüni; Christopher Bartlett; Holenstein F; Jac Sterne
International Journal of Epidemiology | 2002
Peter Jüni; Franziska Holenstein; Jonathan A C Sterne; Christopher Bartlett; Matthias Egger
JAMA | 2001
Matthias Egger; Peter Jüni; Christopher Bartlett
Statistics in Medicine | 2002
Jonathan A C Sterne; Peter Jüni; Kenneth F. Schulz; Douglas G. Altman; Christopher Bartlett; Matthias Egger