Search PubMed⌕ Search

Biomedical subjects

Andrew D Oxman

Publications and source records attributed to Andrew D Oxman.

At least 37 records · Page 2Linked to original sources

Summaries of findings, descriptions of interventions, and information about adverse effects would make reviews more informative.

BACKGROUND AND OBJECTIVE: To describe challenges when extracting and presenting relevant, consistent, and accessible information from systematic reviews. MATERIALS AND METHODS: We systematically selected comparisons and outcomes from 18 Cochrane reviews, evaluated the quality of evidence for each outcome using the GRADE system, and developed standardized patient information. We evaluated the information using patient, review author, researcher, and clinician feedback. RESULTS: Challenges included large numbers of comparisons and outcomes; missing information about treatments and adverse effects; and variations in how effect was measured and presented. By selecting comparisons and outcomes based on patient-relevance, quality, and nonredundancy, we halved the number of outcomes. We prepared information about treatments and adverse effects using other sources. We framed outcomes consistently and standardized the presentation of magnitude of effect. CONCLUSIONS: The incorporation of summary of findings tables in reviews could address these challenges. Problems could also be reduced if review groups agreed upon standard outcomes; excluded less relevant outcomes; incorporated more information about interventions and adverse effects; and implemented clearer guidelines for the presentation of results.

Clinical Trials as Topic↗

Does telling people what they have been doing change what they do? A systematic review of the effects of audit and feedback.

BACKGROUND: Many people advocate audit and feedback as a strategy for improving professional practice. The main results of an update of a Cochrane review on the effects of audit and feedback are reported. DATA SOURCES: The Cochrane Effective Practice and Organisation of Care Group's register up to January 2004 was searched. Randomised trials of audit and feedback that reported objectively measured professional practice in a healthcare setting or healthcare outcomes were included. REVIEW METHODS: Data were independently extracted and the quality of studies were assessed by two reviewers. Quantitative, visual and qualitative analyses were undertaken. MAIN RESULTS: 118 trials are included in the review. In the primary analysis, 88 comparisons from 72 studies were included that compared any intervention in which audit and feedback was a component to no intervention. For dichotomous outcomes, the median-adjusted risk difference of compliance with desired practice was 5% (interquartile range 3-11). For continuous outcomes, the median-adjusted percentage change relative to control was 16% (interquartile range 5-37). Low baseline compliance with recommended practice and higher intensity of audit and feedback appeared to predict the effectiveness of audit and feedback. CONCLUSIONS: Audit and feedback can be effective in improving professional practice. The effects are generally small to moderate. The absolute effects of audit and feedback are likely to be larger when baseline adherence to recommended practice is low and intensity of audit and feedback is high.

Education, Medical, Continuing↗

A surrealistic mega-analysis of redisorganization theories.

BACKGROUND: We are sick and tired of being redisorganized. OBJECTIVE: To systematically review the empirical evidence for organizational theories and repeated reorganizations. METHODS: We did not find anything worth reading, other than Dilbert, so we fantasized. Unfortunately, our fantasies may well resemble many people's realities. We are sorry about this, but it is not our fault. RESULTS: We discovered many reasons for repeated reorganizations, the most common being 'no good reason'. We estimated that trillions of dollars are being spent on strategic and organizational planning activities each year, thus providing lots of good reasons for hundreds of thousands of people, including us, to get into the business. New leaders who are intoxicated with the prospect of change further fuel perpetual cycles of redisorganization. We identified eight indicators of successful redisorganizations, including large consultancy fees paid to friends and relatives. CONCLUSIONS: We propose the establishment of ethics committees to review all future redisorganization proposals in order to put a stop to uncontrolled, unplanned experimentation inflicted providers and users of the health services.

Journal Article↗

Rational prescribing in primary care (RaPP): a cluster randomized trial of a tailored intervention.

BACKGROUND: A gap exists between evidence and practice regarding the management of cardiovascular risk factors. This gap could be narrowed if systematically developed clinical practice guidelines were effectively implemented in clinical practice. We evaluated the effects of a tailored intervention to support the implementation of systematically developed guidelines for the use of antihypertensive and cholesterol-lowering drugs for the primary prevention of cardiovascular disease. METHODS AND FINDINGS: We conducted a cluster-randomized trial comparing a tailored intervention to passive dissemination of guidelines in 146 general practices in two geographical areas in Norway. Each practice was randomized to either the tailored intervention (70 practices; 257 physicians) or control group (69 practices; 244 physicians). Patients started on medication for hypertension or hypercholesterolemia during the study period and all patients already on treatment that consulted their physician during the trial were included. A multifaceted intervention was tailored to address identified barriers to change. Key components were an educational outreach visit with audit and feedback, and computerized reminders linked to the medical record system. Pharmacists conducted the visits. Outcomes were measured for all eligible patients seen in the participating practices during 1 y before and after the intervention. The main outcomes were the proportions of (1) first-time prescriptions for hypertension where thiazides were prescribed, (2) patients assessed for cardiovascular risk before prescribing antihypertensive or cholesterol-lowering drugs, and (3) patients treated for hypertension or hypercholesterolemia for 3 mo or more who had achieved recommended treatment goals. The intervention led to an increase in adherence to guideline recommendations on choice of antihypertensive drug. Thiazides were prescribed to 17% of patients in the intervention group versus 11% in the control group (relative risk 1.94; 95% confidence interval 1.49-2.49, adjusted for baseline differences and clustering effect). Little or no differences were found for risk assessment prior to prescribing and for achievement of treatment goals. CONCLUSIONS: Our tailored intervention had a significant impact on prescribing of antihypertensive drugs, but was ineffective in improving the quality of other aspects of managing hypertension and hypercholesterolemia in primary care.

Anticholesteremic Agents↗

Rational prescribing in primary care (RaPP): economic evaluation of an intervention to improve professional practice.

BACKGROUND: Interventions designed to narrow the gap between research findings and clinical practice may be effective, but also costly. Economic evaluations are necessary to judge whether such interventions are worth the effort. We have evaluated the economic effects of a tailored intervention to support the implementation of guidelines for the use of antihypertensive and cholesterol-lowering drugs. The tailored intervention was evaluated in a randomized trial, and was shown to significantly increase the use of thiazides for patients started on antihypertensive medication, but had little or no impact on other outcomes. The increased use of thiazides was not expected to have an impact on health outcomes. METHODS AND FINDINGS: We performed cost-minimization and cost-effectiveness analyses on data from a randomized trial involving 146 general practices from two geographical areas in Norway. Each practice was randomized to either the tailored intervention (70 practices; 257 physicians) or control group (69 practices; 244 physicians). Only patients that were being started on antihypertensive medication were included in the analyses. A multifaceted intervention was tailored to address identified barriers to change. Key components were an educational outreach visit with audit and feedback, and computerized reminders. Pharmacists conducted the visits. A cost-minimization framework was adopted, where the costs of intervention were set against the reduced treatment costs (principally due to increased use of thiazides rather than more expensive medication). The cost-effectiveness of the intervention was estimated as the cost per additional patient being started on thiazides. The net annual cost (cost minimization) in our study population was 53,395 US dollars, corresponding to 763 US dollars per practice. The cost per additional patient started on thiazides (cost-effectiveness) was 454 US dollars. The net annual savings in a national program was modeled to be 761,998 US dollars, or 540 US dollars per practice after 2 y. In this scenario the savings exceeded the costs in all but two of the sensitivity analyses we conducted, and the cost-effectiveness was estimated to be 183 US dollars. CONCLUSIONS: We found a significant shift in prescribing of antihypertensive drugs towards the use of thiazides in our trial. A major reason to promote the use of thiazides is their lower price compared to other drugs. The cost of the intervention was more than twice the savings within the time frame of our study. However, we predict modest savings over a 2-y period.

Anticholesteremic Agents↗

Translating research into policy and practice in developing countries: a case study of magnesium sulphate for pre-eclampsia.

BACKGROUND: The evidence base for improving reproductive health continues to grow. However, concerns remain that the translation of this evidence into appropriate policies is partial and slow. Little is known about the factors affecting the use of evidence by policy makers and clinicians, particularly in developing countries. The objective of this study was to examine the factors that might affect the translation of randomised controlled trial (RCT) findings into policies and practice in developing countries. METHODS: The recent publication of an important RCT on the use of magnesium sulphate to treat pre-eclampsia provided an opportunity to explore how research findings might be translated into policy. A range of research methods, including a survey, group interview and observations with RCT collaborators and a survey of WHO drug information officers, regulatory officials and obstetricians in 12 countries, were undertaken to identify barriers and facilitators to knowledge translation. RESULTS: It proved difficult to obtain reliable data regarding the availability and use of commonly used drugs in many countries. The perceived barriers to implementing RCT findings regarding the use of magnesium sulphate for pre-eclampsia include drug licensing and availability; inadequate and poorly implemented clinical guidelines; and lack of political support for policy change. However, there were significant regional and national differences in the importance of specific barriers. CONCLUSION: The policy changes needed to ensure widespread availability and use of magnesium sulphate are variable and complex. Difficulties in obtaining information on availability and use are combined with the wide range of barriers across settings, including a lack of support from policy makers. This makes it difficult to envisage any single intervention strategy that might be used to promote the uptake of research findings on magnesium sulphate into policy across the study settings. The publication of important trials may therefore not have the impacts on health care that researchers hope for.

Anticonvulsants↗

Systems for grading the quality of evidence and the strength of recommendations II: pilot study of a new system.

BACKGROUND: Systems that are used by different organisations to grade the quality of evidence and the strength of recommendations vary. They have different strengths and weaknesses. The GRADE Working Group has developed an approach that addresses key shortcomings in these systems. The aim of this study was to pilot test and further develop the GRADE approach to grading evidence and recommendations. METHODS: A GRADE evidence profile consists of two tables: a quality assessment and a summary of findings. Twelve evidence profiles were used in this pilot study. Each evidence profile was made based on information available in a systematic review. Seventeen people were given instructions and independently graded the level of evidence and strength of recommendation for each of the 12 evidence profiles. For each example judgements were collected, summarised and discussed in the group with the aim of improving the proposed grading system. Kappas were calculated as a measure of chance-corrected agreement for the quality of evidence for each outcome for each of the twelve evidence profiles. The seventeen judges were also asked about the ease of understanding and the sensibility of the approach. All of the judgements were recorded and disagreements discussed. RESULTS: There was a varied amount of agreement on the quality of evidence for the outcomes relating to each of the twelve questions (kappa coefficients for agreement beyond chance ranged from 0 to 0.82). However, there was fair agreement about the relative importance of each outcome. There was poor agreement about the balance of benefits and harms and recommendations. Most of the disagreements were easily resolved through discussion. In general we found the GRADE approach to be clear, understandable and sensible. Some modifications were made in the approach and it was agreed that more information was needed in the evidence profiles. CONCLUSION: Judgements about evidence and recommendations are complex. Some subjectivity, especially regarding recommendations, is unavoidable. We believe our system for guiding these complex judgements appropriately balances the need for simplicity with the need for full and transparent consideration of all important issues.

Comprehension↗

Portals to Wonderland: health portals lead to confusing information about the effects of health care.

BACKGROUND: The Internet offers a seemingly endless amount of health information of varying quality. Health portals, which provide entry points to quality-controlled collections of websites, have been hailed as a solution to this problem. The objective of this study is to assess the extent to which government-run health portals provide access to relevant, valid and understandable information about the effects of health care. METHODS: We selected eight clinically relevant questions for which there was a systematic review, searched four portals for answers, and compared the answers we found to the results of the systematic reviews. RESULTS: Our searches resulted in 3400 hits, 155 of which mentioned both the condition and the intervention in one of the eight questions. Sixty-three of the 155 web pages did not give any information about the effect of the intervention. Seventy-seven qualitatively described the effects of the intervention. Twenty-six of these had information that was too unclear to be categorised; 15 were not consistent with the systematic review; and 36 were consistent with the review, but usually did not mention what happens without the intervention, what outcomes have been measured or when they were measured. Fifteen web pages quantitatively described effects. Four of these were abstracts from the systematic review, nine had information that was incomplete and potentially misleading because of a lack of information about people not receiving the intervention and the length of follow-up; one had information that was consistent with the review, but only referred to three trials whereas the review included six; and one was consistent with the review. CONCLUSION: Information accessible through health portals is unlikely to be based on systematic reviews and is often unclear, incomplete and misleading. Portals are only as good as the websites they lead to. Investments in national health portals are unlikely to benefit consumers without investments in the production and maintenance of relevant, valid and understandable information to which the portals lead.

Delivery of Health Care↗

International variation in prescribing antihypertensive drugs: its extent and possible explanations.

BACKGROUND: Inexpensive antihypertensive drugs are at least as effective and safe as more expensive drugs. Overuse of newer, more expensive antihypertensive drugs is a poor use of resources. The potential savings are substantial, but vary across countries, in large part due to differences in prescribing patterns. We wanted to describe prescribing patterns of antihypertensive drugs in ten countries and explore possible reasons for inter-country variation. METHODS: National prescribing profiles were determined based on information on sales and indications for prescribing. We sent a questionnaire to academics and drug regulatory agencies in Canada, France, Germany, UK, US and the Nordic countries, asking about explanations for differences in prescribing patterns in their country compared with the other countries. We also conducted telephone interviews with medical directors of drug companies in the UK and Norway, the countries with the largest differences in prescribing patterns. RESULTS: There is considerable variation in prescribing patterns. In the UK thiazides account for 25% of consumption, while the corresponding figure for Norway is 6%. In Norway alpha-blocking agents account for 8% of consumption, which is more than twice the percentage found in any of the other countries. Suggested factors to explain inter-country variation included reimbursement policies, traditions, opinion leaders with conflicts of interests, domestic pharmaceutical production, and clinical practice guidelines. The medical directors also suggested hypotheses that: Norwegian physicians are early adopters of new interventions while the British are more conservative; there are many clinical trials conducted in Norway involving many general practitioners; there is higher cost-awareness among physicians in the UK, in part due to fund holding; and there are publicly funded pharmaceutical advisors in the UK. CONCLUSION: Two compelling explanations the variation in prescribing that warrant further investigation are the promotion of less-expensive drugs by pharmaceutical advisors in UK and the promotion of more expensive drugs through "seeding trials" in Norway.

Antihypertensive Agents↗

A surrealistic mega-analysis of redisorganization theories.

BACKGROUND: We are sick and tired of being redisorganized. OBJECTIVE: To systematically review the empirical evidence for organizational theories and repeated reorganizations. METHODS: We did not find anything worth reading, other than Dilbert, so we fantasized. Unfortunately, our fantasies may well resemble many people's realities. We are sorry about this, but it is not our fault. RESULTS: We discovered many reasons for repeated reorganizations, the most common being "no good reason". We estimated that trillions of dollars are being spent on strategic and organizational planning activities each year, thus providing lots of good reasons for hundreds of thousands of people, including us, to get into the business. New leaders who are intoxicated with the prospect of change further fuel perpetual cycles of redisorganization. We identified eight indicators of successful redisorganizations, including large consultancy fees paid to friends and relatives. CONCLUSIONS: We propose the establishment of ethics committees to review all future redisorganization proposals in order to put a stop to uncontrolled, unplanned experimentation inflicted on providers and users of the health services.

Consultants↗

Systems for grading the quality of evidence and the strength of recommendations I: critical appraisal of existing approaches The GRADE Working Group.

BACKGROUND: A number of approaches have been used to grade levels of evidence and the strength of recommendations. The use of many different approaches detracts from one of the main reasons for having explicit approaches: to concisely characterise and communicate this information so that it can easily be understood and thereby help people make well-informed decisions. Our objective was to critically appraise six prominent systems for grading levels of evidence and the strength of recommendations as a basis for agreeing on characteristics of a common, sensible approach to grading levels of evidence and the strength of recommendations. METHODS: Six prominent systems for grading levels of evidence and strength of recommendations were selected and someone familiar with each system prepared a description of each of these. Twelve assessors independently evaluated each system based on twelve criteria to assess the sensibility of the different approaches. Systems used by 51 organisations were compared with these six approaches. RESULTS: There was poor agreement about the sensibility of the six systems. Only one of the systems was suitable for all four types of questions we considered (effectiveness, harm, diagnosis and prognosis). None of the systems was considered usable for all of the target groups we considered (professionals, patients and policy makers). The raters found low reproducibility of judgements made using all six systems. Systems used by 51 organisations that sponsor clinical practice guidelines included a number of minor variations of the six systems that we critically appraised. CONCLUSIONS: All of the currently used approaches to grading levels of evidence and the strength of recommendations have important shortcomings.

Advisory Committees↗

Improving prescribing of antihypertensive and cholesterol-lowering drugs: a method for identifying and addressing barriers to change.

BACKGROUND: We describe a simple approach we used to identify barriers and tailor an intervention to improve pharmacological management of hypertension and hypercholesterolaemia. We also report the results of a post hoc exercise and survey we carried out to evaluate our approach for identifying barriers and tailoring interventions. METHODS: We used structured reflection, searched for other relevant trials, surveyed general practitioners and talked with physicians during pilot testing of the intervention. The post hoc exercise was carried out as focus groups of international researchers in the field of quality improvement in health care. The post hoc survey was done by telephone interviews with physicians allocated to the experimental group of a randomised trial of our multifaceted intervention. RESULTS: A wide range of barriers was identified and several interventions were suggested through structured reflection. The survey led to some adjustments. Studying other trials and pilot testing did not lead to changes in the design of the intervention. Neither the post hoc focus groups nor the post hoc survey revealed important barriers or interventions that we had not considered or included in our tailored intervention. CONCLUSIONS: A simple approach to identifying barriers to change appears to have been adequate and efficient. However, we do not know for certain what we would have gained by using more comprehensive methods and we do not know whether the resulting intervention would have been more effective if we had used other methods. The effectiveness of our multifaceted intervention is under evaluation in a randomised controlled trial.

Anticholesteremic Agents↗

Grading quality of evidence and strength of recommendations.

Users of clinical practice guidelines and other recommendations need to know how much confidence they can place in the recommendations. Systematic and explicit methods of making judgments can reduce errors and improve communication. We have developed a system for grading the quality of evidence and the strength of recommendations that can be applied across a wide range of interventions and contexts. In this article we present a summary of our approach from the perspective of a guideline user. Judgments about the strength of a recommendation require consideration of the balance between benefits and harms, the quality of the evidence, translation of the evidence into specific circumstances, and the certainty of the baseline risk. It is also important to consider costs (resource utilisation) before making a recommendation. Inconsistencies among systems for grading the quality of evidence and the strength of recommendations reduce their potential to facilitate critical appraisal and improve communication of these judgments. Our system for guiding these complex judgments balances the need for simplicity with the need for full and transparent consideration of all important issues.

Cost-Benefit Analysis↗

You cannot make informed choices without information.

Informed choices require information that is relevant, valid and accessible. Systematic reviews of the effects of alternative strategies provide information that is essential but not sufficient for recommendations about how best to manage mild brain injury or other problems. Work such as that of the Task Force on Mild Traumatic Brain Injury make decisions easier and better informed. To achieve better outcomes the information derived from systematic reviews needs to be applied critically and well-informed, context specific recommendations must be effectively implemented.

Choice Behavior↗

Letters, numbers, symbols and words: how to communicate grades of evidence and recommendations.

The GRADE Working Group is developing and evaluating a common, sensible approach to grading quality of evidence and strength of recommendations in health care. In this article, we discuss the advantages and disadvantages of using letters, numbers, symbols or words to represent grades of evidence and recommendations. Using multiple strategies, we searched for comparative studies of alternative ways of representing ordered categories in any context. In addition, we contacted experts and reviewed theoretical work and qualitative research on how best to communicate grades of any kind quickly and clearly. We were unable to identify health care research that addressed, either directly or indirectly, the best way to present grades of evidence and recommendations. We found examples of symbols used by government, commercial and consumer organizations to communicate quality of evidence or strength of recommendations, but no comparative studies. Although a number of grading systems are used in health care and other fields, there is little or no evidence of how well various presentations are understood. Before promoting the use of specific symbols, numbers, letters or words, the extent to which the intended message is comprehended should be evaluated.

Communication↗