Showing papers in "BMJ in 1995"

Qualitative Research: Introducing focus groups

Abstract: This paper introduces focus group methodology, gives advice on group composition, running the groups, and analysing the results. Focus groups have advantages for researchers in the field of health and medicine: they do not discriminate against people who cannot read or write and they can encourage participation from people reluctant to be interviewed on their own or who feel they have nothing to say. This is the fifth in a series of seven articles describing non-quantitative techniques and showing their value in health research **FIGURE OMITTED** Focus groups are a form of group interview that capitalises on communication between research participants in order to generate data. Although group interviews are often used simply as a quick and convenient way to collect data from several people simultaneously, focus groups explicitly use group interaction as part of the method. This means that instead of the researcher asking each person to respond to a question in turn, people are encouraged to talk to one another: asking questions, exchanging anecdotes and commenting on each other's experiences and points of view.1 The method is particularly useful for exploring people's knowledge and experiences and can be used to examine not only what people think but how they think and why they think that way. Focus groups were originally used within communication studies to explore the effects of films and television programmes,2 and are a popular method for assessing health education messages and examining public understandings of illness and of health behaviours.3 4 5 6 7 They are widely used to examine people's experiences of disease and of health services.8 9 and are an effective technique for exploring the attitudes and needs of staff.10 11 The idea behind the focus group method is that group processes can help people to explore and …

Descartes' Error: Emotion, Reason and the Human Brain

Abstract: Antonio R Damasio Picador, pounds sterling16.99, pp 312 ISBN 0 330 33927 3 Documentary makers find the brain sexy at present; surf the television channels and the workings of the psyche are hard to avoid: violence, paraphilias, psychopathy, all are explained. Brain books are similarly popular. They come in three varieties. There is the “you're only” school: you're only a cluster of neurons (Francis Crick), processes (Daniel Dennett), microtubules (Sir Roger Penrose) and so on in a reductionist vein. Humans are considered from a pathological/laboratory perspective. Computer metaphors abound (your mind is your software!) and there are boxes and arrows in profusion. Such books …

Multiple significance tests: the Bonferroni method

Abstract: Many published papers include large numbers of significance tests. These may be difficult to interpret because if we go on testing long enough we will inevitably find something which is “significant.” We must beware of attaching too much importance to a lone significant result among a mass of non-significant ones. It may be the one in 20 which we expect by chance alone. Lee et al simulated a clinical trial of the treatment of coronary artery disease by allocating 1073 patient records from past cases into two “treatment” groups at random.1 They then analysed the outcome as if it were a genuine trial of two treatments. The analysis was quite detailed and thorough. As we would expect, it failed to show any significant difference in survival between those patients allocated to the two treatments. Patients were then subdivided by two variables which affect prognosis, the number of diseased coronary vessels and whether the left ventricular contraction pattern was normal or abnormal. A significant difference in survival between the two “treatment” groups was found in those patients with three diseased vessels (the maximum) and abnormal ventricular contraction. As this would be the subset of patients with the worst prognosis, the finding would be easy to account for by saying that the superior “treatment” …

Fetal origins of coronary heart disease

Abstract: The fetal origins hypothesis states that fetal undernutrition in middle to late gestation, which leads to disproportionate fetal growth, programmes later coronary heart disease. Animal studies have shown that undernutrition before birth programmes persisting changes in a range of metabolic, physiological, and structural parameters. Studies in humans have shown that men and women whose birth weights were at the lower end of the normal range, who were thin or short at birth, or who were small in relation to placental size have increased rates of coronary heart disease. We are beginning to understand something of the mechanisms underlying these associations. The programming of blood pressure, insulin responses to glucose, cholesterol metabolism, blood coagulation, and hormonal settings are all areas of active research.

Consensus methods for medical and health services research.

Abstract: Health providers face the problem of trying to make decisions in situations where there is insufficient information and also where there is an overload of (often contradictory) information. Statistical methods such as meta-analysis have been developed to summarise and to resolve inconsistencies in study findings—where information is available in an appropriate form. Consensus methods provide another means of synthesising information, but are liable to use a wider range of information than is common in statistical methods, and where published information is inadequate or non-existent these methods provide a means of harnessing the insights of appropriate experts to enable decisions to be made. Two consensus methods commonly adopted in medical, nursing, and health services research—the Delphi process and the nominal group technique (also known as the expert panel)—are described, together with the most appropriate situations for using them; an outline of the process involved in undertaking a study using each method is supplemented by illustrations of the authors' work. Key methodological issues in using the methods are discussed, along with the distinct contribution of consensus methods as aids to decision making, both in clinical practice and in health service development. This is the sixth in a series of seven articles describing non-quantitative techniquesand showing their value in health research Quantitative methods such as meta-analysis have been developed to provide statistical overviews of the results of clinical trials and to resolve inconsistencies in the results of published studies. Consensus methods are another means of dealing with conflicting scientific evidence. They allow a wider range of study types to be considered than is usual in statistical reviews. In addition they allow a greater role for the qualitative assessment of evidence (box 1). These methods, unlike those described in the other papers in this series, are primarily concerned with deriving quantitative estimates through qualitative …

Rigour and qualitative research.

Abstract: Various strategies are available within qualitative research to protect against bias and enhance the reliability of findings This paper gives examples of the principal approaches and summarises them into a methodological checklist to help readers of reports of qualitative projects to assess the quality of the research In the health field--with its strong tradition of biomedical research using conventional, quantitative, and often experimental methods--qualitative research is often criticised for lacking scientific rigour To label an approach “unscientific” is peculiarly damning in an era when scientific knowledge is generally regarded as the highest form of knowing The most commonly heard criticisms are, firstly, that qualitative research is merely an assembly of anecdote and personal impressions, strongly subject to researcher bias; secondly, it is argued that qualiative research lacks reproducibility--the research is so personal to the researcher that there is no guarantee that a different researcher would not come to radically different conclusions; and, finally, qualitative research is criticised for lacking generalisability It is said that qualitative methods tend to generate large amounts of detailed information about a small number of settings The pervasive assumption underlying all these criticisms is that quantitative and qualitative approaches are fundamentally different in their ability to ensure the validity and reliability of their findings This distinction, however, is more one of degree than of type The problem of the relation of a piece of research to some presumed underlying “truth” applies to the conduct of any form of social research “One of the greatest methodological fallacies of the last half century in social research is the belief that science is a particular set of techniques; it is, rather, a state of mind, or attitude, and the organisational conditions which allow that attitude to be expressed”1 In quantitative data analysis it is possible to generate statistical …

Reaching the parts other methods cannot reach: an introduction to qualitative methods in health and health services research.

Abstract: Qualitative research methods have a long history in the social sciences and deserve to be an essential component in health and health services research. Qualitative and quantitative approaches to research tend to be portrayed as antithetical; the aim of this series of papers is to show the value of a range of qualitative techniques and how they can complement quantitative research. Medical advances, increasing specialisation, rising patient expectations, and the sheer size and diversity of health service provision mean that today's health professionals work in an increasingly complex arena. The wide range of research questions generated by this complexity has encouraged the search for new ways of conducting research. The rapid expansion of research on and about health and health services, and the relatively recent demarcation of a distinct field of “health services research” depend heavily on doctors and other health professionals being investigators, participants, and peer reviewers. Yet some of the most important questions in health services concern the organisation and culture of those who provide health care, such as why the findings of randomised controlled trials are often difficult to apply in day to day clinical practice. The social science methods appropriate to studying such phenomena are very different from the methods familiar to many health professionals. Although the more qualitative approaches found in certain of the social sciences may seem alien alongside the experimental, quantitative methods used in clinical and biomedical research, they should be an essential component of health services research--not just because they enable us to access areas not amenable to quantitative research, such as lay and professional health beliefs, but also because qualitative description is a prerequisite of good quantitative research, particularly in areas that have received little previous investigation. A good example of this is the study of the social consequences of the …

Endarterectomy for asymptomatic carotid artery stenosis

Abstract: Reasonable doubt justifies randomisation European and North American clinicians have always differed in their management of carotid artery disease.1 Carotid endarterectomy is one of the commonest vascular procedures in North America, with over 360 operations per million population being performed each year.1 Meanwhile, despite the fact that the first carotid reconstruction was performed in Britain,1 selection for the procedure in Europe has been sporadic. British data for 1993-4 confirm that fewer than 40 carotid endarterectomies are performed per million population per year (personal communications from Department of Health, England; NHS Information and Statistics Division, Scotland; and Department of Health and Social Services, Northern Ireland, 1995). Two major multicentre trials, the North American symptomatic carotid endarterectomy trial and the European carotid surgery trial, both published in 1991, have helped to define the role of carotid endarterectomy in patients with symptoms, such as transient ischaemic attacks and non-disabling strokes.2 3 In symptomatic patients with an internal carotid artery stenosis of greater than 70%, endarterectomy produced a 75% reduction in rates of stroke over two to three years when compared with best medical treatment. These trials meant that carotid endarterectomy became a member of that small group of preventive surgical procedures that have withstood the test of a randomised controlled trial. Neurologists' lack of confidence in the outcome of carotid endarterectomy has contributed to low rates of referral in Europe.1 The benefit to patients with symptoms is acknowledged, but the impact of the operation on preventing stroke in the population has been challenged, as highlighted recently in the BMJ.4 Health service statistics suggest that the provision of endarterectomy for symptomatic patients is not uniform across the country. Given that Britain cannot optimally provide for patients …

Community study of role of viral infections in exacerbations of asthma in 9-11 year old children.

Abstract: Objective: To study the association between upper and lower respiratory viral infections and acute exacerbations of asthma in schoolchildren in the community. Design: Community based 13 month longitudinal study using diary card respiratory symptom and peak expiratory flow monitoring to allow early sampling for viruses. Subjects: 108 Children aged 9-11 years who had reported wheeze or cough, or both, in a questionnaire. Setting: Southampton and surrounding community. Main outcome measures: Upper and lower respiratory viral infections detected by polymerase chain reaction or conventional methods, reported exacerbations of asthma, computer identified episodes of respiratory tract symptoms or peak flow reductions. Results: Viruses were detected in 80% of reported episodes of reduced peak expiratory flow, 80% of reported episodes of wheeze, and in 85% of reported episodes of upper respiratory symptoms, cough, wheeze, and a fall in peak expiratory flow. The median duration of reported falls in peak expiratory flow was 14 days, and the median maximum fall in peak expiratory flow was 81 1/min. The most commonly identified virus type was rhinovirus. Conclusions: This study supports the hypothesis that upper respiratory viral infections are associated with 80-85% of asthma exacerbations in school age children. Key messages Key messages In this study common cold viruses were found in 80-85% of reported exacerbations of asthma in children Rhinoviruses, which cause most common colds, accounted for two thirds of viruses detected Analysis of diary cards also showed large numbers of similar but less severe episodes that may also be viral in origin

Waist circumference as a measure for indicating need for weight management

Abstract: Objective : To test the hypothesis that a single measurement, waist circumference, might be used to identify people at health risk both from being overweight and from having a central fat distribution. Design : A community derived random sample of men and women and a second, validation sample. Setting : North Glasgow. Subjects : 904 men and 1014 women (first sample); 86 men and 202 women (validation sample). Main outcome measures : Waist circumference, body mass index, waist:hip ratio. Results : Waist circumference >/=94 cm for men and >/=80 cm for women identified subjects with high body mass index (>/=25 kg/m 2 ) and those with lower body mass index but high waist:hip ratio (>/=0.95 for men, >/=0.80 women) with a sensitivity of >96% and specificity >97.5%. Waist circumference >/=102 cm for men or >/=88 cm for women identified subjects with body mass index >/=30 and those with lower body mass index but high waist:hip ratio with a sensitivity of >96% and specificity >98%, with only about 2% of the sample being misclassified. Conclusions : Waist circumference could be used in health promotion programmes to identify individuals who should seek and be offered weight management. Men with waist circumference >/=94 cm and women with waist circumference >/=80 cm should gain no further weight; men with waist circumference >/=102 cm and women with waist circumference >/=88 cm should reduce their weight.

Qualitative interviews in medical research.

Abstract: Much qualitative research is interview based, and this paper provides an outline of qualitative interview techniques and their application in medical settings. It explains the rationale for these techniques and shows how they can be used to research kinds of questions that are different from those dealt with by quantitative methods. Different types of qualitative interviews are described, and the way in which they differ from clinical consultations is emphasised. Practical guidance for conducting such interviews is given.

Ways with words

Abstract: I was delighted to hear that the BMJ (British Medical Journal) had accepted an advertisement for the BMJ (Builders Merchants Journal). It confirmed a long held belief in the abomination of abbreviations and the arrogance of those who use them, expecting others to know what they are talking about. Over the years I have collected many examples with a similar potential for confusion. A simple case might be BP: …

The number needed to treat: a clinically useful measure of treatment effect.

Abstract: The relative benefit of an active treatment over a control is usually expressed as the relative risk, the relative risk reduction, or the odds ratio. These measures are used extensively in both clinical and epidemiological investigations. For clinical decision making, however, it is more meaningful to use the measure "number needed to treat." This measure is calculated on the inverse of the absolute risk reduction. It has the advantage that it conveys both statistical and clinical significance to the doctor. Furthermore, it can be used to extrapolate published findings to a patient at an arbitrary specified baseline risk when the relative risk reduction associated with treatment is constant for all levels of risk.

Absence of evidence is not evidence of absence

Abstract: PIP: Randomized controlled clinical trials are conducted to determine whether differences of clinical importance exist between selected treatment regimens. When statistical analysis of the study data finds a P value greater than 5%, it is convention to deem the assessed difference nonsignificant. Just because convention dictates that such study findings be termed nonsignificant, or negative, however, it does not necessarily follow that the study found nothing of clinical importance. Subject samples used in controlled trials tend to be too small. The studies therefore lack the necessary power to detect real, and clinically worthwhile, differences in treatment. Freiman et al. found that only 30% of a sample of 71 trials published in the New England Journal of Medicine in 1978-79 with a P value greater than 10% were large enough to have a 90% chance of detecting even a 50% difference in the effectiveness of the treatments being compared, and they found no improvement in a similar sample of trials published in 1988. It is therefore wrong and unwise to interpret so many negative trials as providing evidence of the ineffectiveness of new treatments. One must instead seriously question whether the absence of evidence is a valid justification for inaction. Efforts must be made to look for quantification of an association rather than just a P value, especially when the risks under investigation are small. The authors cite a recent trial comparing octreotide and sclerotherapy in patients with variceal bleeding, as well as the overview of clinical trials evaluating fibrinolytic treatment for preventing reinfarction after acute myocardial infarction as examples.

Obesity in Britain: gluttony or sloth?

Abstract: The prevalence of clinical obesity in Britain has doubled in the past decade. The Health of the Nation initiative has set ambitious targets for reversing the trend in recognition of the serious health burden which will accrue, but efforts to develop prevention and treatment strategies are handicapped by uncertainty as to the aetiology of the problem. It is generally assumed that ready access to highly palatable foods induces excess consumption and that obesity is caused by simple gluttony. There is evidence that a high fat diet does override normal satiety mechanisms. However, average recorded energy intake in Britain has declined substantially as obesity rates have escalated. The implication is that levels of physical activity, and hence energy needs, have declined even faster. Evidence suggests that modern inactive lifestyles are at least as important as diet in the aetiology of obesity and possibly represent the dominant factor.

Evidence based medicine: an approach to clinical problem-solving

Abstract: Doctors within the NHS are confronting major changes at work. While we endeavour to improve the quality of health care, junior doctors' hours have been reduced and the emphasis on continuing medical education has increased. We are confronted by a growing body of information, much of it invalid or irrelevant to clinical practice. This article discusses evidence based medicine, a process of turning clinical problems into questions and then systematically locating, appraising, and using contemporaneous research findings as the basis for clinical decisions. The computerisation of bibliographies and the development of software that permits the rapid location of relevant evidence have made it easier for busy clinicians to make best use of the published literature. Critical appraisal can be used to determine the validity and applicability of the evidence, which is then used to inform clinical decisions. Evidence based medicine can be taught to, and practised by, clinicians at all levels of seniority and can be used to close the gulf between good clinical research and clinical practice. In addition it can help to promote self directed learning and teamwork and produce faster and better doctors.

Diet and overall survival in elderly people

Abstract: Objective : To assess the influence of a specific dietary pattern on overall survival. Design : Cohort study. Setting : Three rural Greek villages, the data from which were collected as part of an international cross cultural study of food habits in later life. Subjects : 182 elderly residents of the three villages. Main outcome measure : Overall mortality. Results : Diet was assessed with a validated extensive semiquantitative questionnaire on food intake. A one unit increase in diet score, devised a priori on the basis of eight component characteristics of the traditional common diet in the Mediterranean region, was associated with a significant 17% reduction in overall mortality (95% confidence interval 1% to 31%). Conclusion : A diet meeting currently understood health criteria does predict survival among people.

Waist circumference action levels in the identification of cardiovascular risk factors: prevalence study in a random sample

Abstract: Objective: To determine the frequency of cardiovascular risk factors in people categorised by previously defined “action g126 levels” of waist circumference. Design: Prevalence study in a random population sample. Setting: Netherlands. Subjects: 2183 men and 2698 women aged 20-59 years selected at random from the civil registry of Amsterdam and Maastricht. Main outcome measures: Waist circumference, waist to hip ratio, body mass index (weight (kg)/height (m2)), total plasma cholesterol concentration, high density lipoprotein cholesterol concentration, blood pressure, age, and lifestyle. Results: A waist circumference exceeding 94 cm in men and 80 cm in women correctly identified subjects with body mass index of >/=25 and waist to hip ratios >/=0.95 in men and >/=0.80 in women with a sensitivity and specificity of >/=96%. Men and women with at least one cardiovascular risk factor (total cholesterol >/=6.5 mmol/l, high density lipoprotein cholesterol /=160 mm Hg, diastolic blood pressure >/=95 mm Hg) were identified with sensitivities of 57% and 67% and specificities of 72% and 62% respectively. Compared with those with waist measurements below action levels, age and lifestyle adjusted odds ratios for having at least one risk factor were 2.2 (95% confidence interval 1.8 to 2.8) in men with a waist measurement of 94-102 cm and 1.6 (1.3 to 2.1) in women with a waist measurement of 80-88 cm. In men and women with larger waist measurements these age and lifestyle adjusted odds ratios were 4.6 (3.5 to 6.0) and 2.6 (2.0 to 3.2) respectively. Conclusions: Larger waist circumference identifies people at increased cardiovascular risks.

Calculating correlation coefficients with repeated observations: Part 2—correlation between subjects

Abstract: In earlier Statistics Notes1 2 we commented on the analysis of paired data where there is more than one observation per subject. It can be highly misleading to analyse such data by combining repeated observations from several subjects and then calculating the correlation coefficient as if the data were a simple sample.1 The appropriate analysis depends on the question we wish to answer. If we want to know whether an increase in one variable within the individual is associated with an increase in the other we can calculate the correlation coefficient within subjects.2 If we want to know whether subjects with high values of one variable also tend to have …

Statistics notes: Calculating correlation coefficients with repeated observations: Part 1—correlation within subjects

Abstract: In an earlier Statistics Note1 we commented on the analysis of paired data where there is more than one observation per subject, as shown in table I. We pointed out that it could be highly misleading to analyse such data by combining repeated observations from several subjects and then calculating the correlation coefficient as if the data were a simple sample. This note is a response to several letters about the appropriate analysis for such data. View this table: TABLE I Repeated measurements of intramural pH and PaCO2 for eight subjects2 The choice of analysis for the data in table I depends on the question we want to …

Sleep related vehicle accidents.

Abstract: Objectives: To assess the incidence, time of day, and driver morbidity associated with vehicle accidents where the most likely cause was the driver falling asleep at the wheel. Design: Two surveys were undertaken, in southwest England and the midlands, by using police databases or on the spot interviews. Subjects: Drivers involved in 679 sleep related vehicle accidents. Results: Of all vehicle accidents to which the police were summoned, sleep related vehicle accidents comprised 16% on major roads in southwest England, and over 20% on midland motorways. During the 24 hour period there were three major peaks: at around 0200, 0600, and 1600. About half these drivers were men under 30 years; few such accidents involved women. Conclusions: Sleep related vehicle accidents are largely dependent on the time of day and account for a considerable proportion of vehicle accidents, especially those on motorways and other monotonous roads. As there are no norms for the United Kingdom on road use by age and sex for time of day with which to compare these data, we cannot determine what the hourly exposure v risk factors are for these subgroups. The findings are in close agreement with those from other countries. Key messages Key messages Such accidents accounted for about 16% of road accidents in general and over 20% for motorways There were clear time of day (circadian) effects with the most vulnerable times being around 2-7 am and in the mid-afternoon Young male drivers accounted for half these accidents, but it is unknown whether these men are more exposed or are particularly at risk The morbidity and mortality associated with sleep related accidents is higher, probably because of the greater speed on impact

Incidence of and mortality from acute upper gastrointestinal haemorrhage in the United Kingdom

Abstract: Objective: To describe the current epidemiology of acute upper gastrointestinal haemorrhage. Design: Population based, unselected, multicentre, prospective survey. Setting: 74 hospitals receiving emergency admissions in four health regions in the United Kingdom. Subjects: 4185 cases of acute upper gastrointestinal haemorrhage in which patients were aged over 16 years identified over four months. Outcome measures: Incidence and mortality. Results: The overall incidence of acute upper gastrointestinal haemorrhage in the United Kingdom is 103/100000 adults per year. The incidence rises from 23 in those aged under 30 to 485 in those aged over 75. At all ages incidence in men was more than double that in women except in elderly patients. 14% of the haemorrhages occurred in inpatients already in hospital for some other reason. In 27% of cases (37% female, 19% male) patients were aged over 80. Overall mortality was 14% (11% in emergency admissions and 33% in haemorrhage in inpatients). In the emergency admissions, 65% of deaths in those aged under 80 were associated with malignancy or organ failure at presentation. Mortality for patients under 60 in the absence of malignancy or organ failure at presentation was 0.8%. Conclusions: The incidence of acute upper gastrointestinal haemorrhage is twice that previously reported in England and similar to that reported in Scotland. The incidence increases appreciably with age. Although the proportion of elderly patients continues to rise and mortality increases steeply with age, age standardised mortality is lower than in earlier studies. Deaths occurred almost exclusively in very old patients or those with severe comorbidity.

Prevalence of Alzheimer's disease and vascular dementia: association with education. The Rotterdam study.

Abstract: Objective: To estimate the prevalence of dementia and its subtypes in the general population and examine the relation of the disease to education. Design: Population based cross sectional study. Setting: Ommoord, a suburb of Rotterdam. Subjects: 7528 participants of the Rotterdam study aged 55-106 years. Results: 474 cases of dementia were detected, giving an overall prevalence of 6.3%. Prevalence ranged from 0.4% (5/1181 subjects) at age 55-59 years to 43.2% (19/44) at 95 years and over. Alzheimer9s disease was the main subdiagnosis (339 cases; 72%); it was also the main cause of the pronounced increase in dementia with age. The relative proportion of vascular dementia (76 cases; 16%), Parkinson9s disease dementia (30; 6%), and other dementias (24; 5%) decreased with age. A substantially higher prevalence of dementia was found in subjects with a low level of education. The association with education was not due to confounding by cardiovascular disease. Conclusions: The prevalence of dementia increases exponentially with age. About one third of the population aged 85 and over has dementia. Three quarters of all dementia is due to Alzheimer9s disease. In this study an inverse dose-response relation was found between education and dementia—in particular, Alzheimer9s disease. Key messages Key messages Of all cases of dementia, 72% were cases of Alzheimer9s disease The pronounced increase in prevalence of dementia with age was due to a substantial increase in Alzheimer9s disease Alzheimer9s disease was more often diagnosed in less educated people The association between dementia and education could not be explained by cardiovascular disease comorbidity

Identifying relevant studies for systematic reviews.

Abstract: EDITOR,—Carl Counsell and Hazel Fraser make a useful point when they describe the different methods of identifying trials used by the Cochrane Stroke Review Group: electronic searches, review of cited papers, searches of registers of trials, and communication with individual …

Dietary underreporting by obese individuals--is it specific or non-specific?

Abstract: Objective: To examine the distribution of patterns of macronutrient density in relation to obesity. Design: Cross sectional. Setting: Denmark. Subjects: 323 men and women aged 35-65 years, selected randomly from a larger population sample of Danish adults. Main outcome measure: Bias in dietary reporting of energy and protein intake in relation to percentage body fat, assessed by comparison of data from an interview on dietary intake with data estimated from 24 hour nitrogen output, validated by administering p-aminobenzoic acid, and estimated 24 hour energy expenditure. Results: Degree of obesity was positively associated with underreporting of total energy and protein, whereas compared with total energy reported, protein was overreported by the obese subjects. Conclusion: Errors in dietary reporting of protein seem to occur disproportionately with respect to total energy, suggesting a differential reporting pattern of different foods. Although, on average, all subjects showed a greater underreporting of energy than of protein, this was most common in the obese subjects. Snack-type foods may be preferentially forgotten when obese people omit food items in dietary reporting. These results seem to agree with the general assumption that obese people tend to underreport fatty foods and foods rich in carbohydrates rather than underreport their total dietary intake. These results may have implications for the interpretation of studies of diet and comorbidities related to obesity.

Anticonvulsant drugs for management of pain: a systematic review.

Abstract: Objective: To determine effectiveness and adverse effects of anticonvulsant drugs in management of pain. Design: Systematic review of randomised controlled trials of anticonvulsants for acute, chronic, or cancer pain identified by using Medline, by hand searching, by searching reference lists, and by contacting investigators. Subjects: Between 1966 and February 1994, 37 reports were found; 20 reports, of four anticonvulsants, were eligible. Main outcome measures: Numbers needed to treat were calculated for effectiveness, adverse effects, and drug related withdrawal from study. Results: The only placebo controlled study in acute pain found no analgesic effect of sodium valproate. For treating trigeminal neuralgia, carbamazepine had a combined number needed to treat of 2.6 for effectiveness, 3.4 for adverse effects, and 24 for severe effects (withdrawal from study). For treating diabetic neuropathy, anticonvulsants had a combined number needed to treat of 2.5 for effectiveness, 3.1 for adverse effects, and 20 for severe effects. For migraine prophylaxis, anticonvulsants had a combined number needed to treat of 1.6 for effectiveness, 2.4 for adverse effects, and 39 for severe effects. Phenytoin had no effect on the irritable bowel syndrome, and carbamazepine had little effect on pain after stroke. Clonazepam was effective in one study for temporomandibular joint dysfunction. No study compared one anticonvulsant with another. Conclusions: Anticonvulsants were effective for trigeminal neuralgia and diabetic neuropathy and for migraine prophylaxis. Minor adverse effects occurred as often as benefit.

Mortality associated with moderate intakes of wine, beer, or spirits.

Abstract: Objective : To examine the association between intake of different types of alcoholic drinks and mortality. Design : Prospective population study with base-line assessment of alcohol intake, smoking habit, income, education, and body mass index, and 10-12 years9 follow up of mortality. Setting : Copenhagen city heart study, Denmark. Subjects : 6051 men and 7234 women aged 30-70 years. Main outcome measure : Number and time of cause-specific deaths from 1976 to 1988. Results : The risk of dying steadily decreased with an increasing intake of wine—from a relative risk of 1.00 for the subjects who never drank wine to 0.51 (95% confidence interval 0.32 to 0.81) for those who drank three to five glasses a day. Intake of neither beer nor spirits, however, was associated with reduced risk. For spirits intake the relative risk of dying increased from 1.00 for those who never drank to 1.34 (1.05 to 1.71) for those with an intake of three to five drinks a day. The effects of the three types of alcoholic drinks seemed to be independent of each other, and no significant interactions existed with sex, age, education, income, smoking, or body mass index. Wine drinking showed the same relation to risk of death from cardiovascular and cerebrovascular disease as to risk of death from all causes. Conclusion : Low to moderate intake of wine is associated with lower mortality from cardiovascular and cerebrovascular disease and other causes. Similar intake of spirits implied an increased risk, while beer drinking did not affect mortality. Key messages Key messages Alcohol in small doses is assumed to protect against ischaemic heart disease In this study drinkers of three to five glasses of wine a day had half the risk of dying as those who never drank wine Beer and spirit drinkers experienced no such advantages, and three to five drinks of spirits a day was associated with increased mortality The U shaped risk function may be a result of a combination of the risk functions of wine, beer, and spirits

Prospective study of cigarette smoking, alcohol use, and the risk of diabetes in men.

Abstract: Objective : To examine the association between smoking, alcohol consumption, and the incidence of non-insulin dependent diabetes mellitus in men of middle years and older. Design : Cohort questionnaire study of men followed up for six years from 1986. Setting : The health professionals9 follow up study being conducted across the United States. Subjects : 41810 male health professionals aged 40-75 years and free of diabetes, cardiovascular disease, and cancer in 1986 and followed up for six years. Main outcome measure : Incidence of non-insulin dependent diabetes mellitus diagnosed in the six years. Results : During 230 769 person years of follow up 509 men were newly diagnosed with diabetes. After controlling for known risk factors men who smoked 25 or more cigarettes daily had a relative risk of diabetes of 1.94 (95% confidence interval 1.25 to 3.03) compared with non-smokers. Men who consumed higher amounts of alcohol had a reduced risk of diabetes (P for trend Conclusions : Cigarette smoking may be an independent, modifiable risk factor for non-insulin dependent diabetes mellitus. Moderate alcohol consumption among healthy people may be associated with increased insulin sensitivity and a reduced risk of diabetes. Key messages Key messages Epidemiological studies have not adequately examined the independent associations between smoking, alcohol, and the risk of diabetes after accounting for obesity This paper shows that current smoking roughly doubles the risk of diabetes among a healthy population of men Moderate alcohol consumption, however, significantly decreases the risk of diabetes Smoking and alcohol may alter the risk of diabetes through long term effects on insulin secretion and insulin resistance

Association of Helicobacter pylori and Chlamydia pneumoniae infections with coronary heart disease and cardiovascular risk factors

Abstract: Objective: To investigate the relation between seropositivity to chronic infections with Helicobacter pylori and Chlamydia pneumoniae and both coronary heart disease and cardiovascular risk factors. Objective:To investigate the relation between seropositivity to chronic infections with Helicobacter pylori and Chlamydia pneumoniae and both coronary heart disease and cardiovascular risk factors. Setting: General practices in Merton, Sutton, and Wandsworth, south London. Subjects: 388 white south London men aged 50-69. Main outcome measures: Evidence of coronary risk factors and infection with H pylori or C pneumoniae. Results: 47 men (12.1%) had electrocardiographic evidence of ischaemia or infarction. 36 (76.6%) and 18 (38.3%) were seropositive for H pylori and C pneumoniae, respectively, compared with 155 (45.5%) and 62 (18.2%) men with normal electrocardiograms. Odds ratios for abnormal electrocardiograms were 3.82 (95% confidence interval 1.60 to 9.10) and 3.06 (12.33 to 7.01) in men seropositive for H pylori and C pneumoniae, respectively, after adjustment for a range of socioeconomic indicators and risk factors for coronary heart disease. Cardiovascular risk factors that were independently associated with seropositivity to H pylori included fibrinogen concentration and total leucocyte count. Seropositivity to C pneumoniae was independently associated with raised fibrinogen and malondialdehyde concentrations. Conclusions: Both H pylori and C pneumoniae infections are associated with coronary heart disease. These relations are not explained by a wide range of confounding factors. Possible mechanisms include an increase in risk factor levels due to a low grade chronic inflammatory response.

Incidence and consequences of falls due to stroke: a systematic inquiry.

Abstract: Objective : To undertake a systematic inquiry into the incidence and consequences of falls in a cohort of elderly patients with stroke after discharge from hospital. Design : Administration of a questionnaire to patients and main carers at discharge from hospital and eight weeks and six months later. Setting : Bradford Metropolitan District. Subjects : 108 patients recruited to the Bradford community stroke trial. Patients were recruited to the trial if they were 60 years or over and resident at home with some residual disability. Main outcome measures : Number of falls, motor club assessment, Barthel index, Frenchay activities index, and Nottingham health profile. Stress in carers was indicated by the general health questionnaire. Results : Of 108 patients, 79 (73%) fell in the six months after discharge from hospital with a total of 270 falls reported. Patients who fell in hospital were significantly more likely to fall at least twice at home after discharge (x 2 =8.16; P=0.004). “Fallers” (two or more falls) were less socially active at six months and more had depressed mood. Carers of these patients were significantly more stressed at six months (53% v 18%; x 2 =8.5; P=0.003). Conclusion : Stroke is associated with a risk of falling at home and affects the lives of patients with stroke and their carers. Falling and fear of falling is an important issue which needs to be dealt with by the multidisciplinary team.