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R B Haynes

Publications and source records attributed to R B Haynes.

At least 19 recordsLinked to original sources
PubMed2000

Users' Guides to the Medical Literature: XXV. Evidence-based medicine: principles for applying the Users' Guides to patient care. Evidence-Based Medicine Working Group.

This series provides clinicians with strategies and tools to interpret and integrate evidence from published research in their care of patients. The 2 key principles for applying all the articles in this series to patient care relate to the value-laden nature of clinical decisions and to the hierarchy of evidence postulated by evidence-based medicine. Clinicians need to be able to distinguish high from low quality in primary studies, systematic reviews, practice guidelines, and other integrative research focused on management recommendations. An evidence-based practitioner must also understand the patient's circumstances or predicament; identify knowledge gaps and frame questions to fill those gaps; conduct an efficient literature search; critically appraise the research evidence; and apply that evidence to patient care. However, treatment judgments often reflect clinician or societal values concerning whether intervention benefits are worth the cost. Many unanswered questions concerning how to elicit preferences and how to incorporate them in clinical encounters constitute an enormously challenging frontier for evidence-based medicine. Time limitation remains the biggest obstacle to evidence-based practice but clinicians should seek evidence from as high in the appropriate hierarchy of evidence as possible, and every clinical decision should be geared toward the particular circumstances of the patient.

Clinical Competence↗
PubMed2000

A randomized trial of improved weight loss with a prepared meal plan in overweight and obese patients: impact on cardiovascular risk reduction.

OBJECTIVE: To assess the long-term effects of a prepackaged, nutritionally complete, prepared meal plan compared with a usual-care diet (UCD) on weight loss and cardiovascular risk factors in overweight and obese persons. DESIGN: In this randomized multicenter study, 302 persons with hypertension and dyslipidemia (n = 183) or with type 2 diabetes mellitus (n = 119) were randomized to the nutrient-fortified prepared meal plan (approximately 22% energy from fat, 58% from carbohydrate, and 20% from protein) or to a macronutrient-equivalent UCD. MAIN OUTCOME MEASURES: The primary outcome measure was weight change. Secondary measures were changes in blood pressure or plasma lipid, lipoprotein, glucose, or glycosylated hemoglobin levels; quality of life; nutrient intake; and dietary compliance. RESULTS: After 1 year, weight change in the hypertension/dyslipidemia group was -5.8+/-6.8 kg with the prepared meal plan vs -1.7+/-6.5 kg with the UCD plan (P<.001); for the type 2 diabetes mellitus group, the change was -3.0+/-5.4 kg with the prepared meal plan vs -1.0+/-3.8 kg with the UCD plan (P<.001) (data given as mean +/- SD). In both groups, both interventions improved blood pressure, total and low-density lipoprotein cholesterol levels, glycosylated hemoglobin level, and quality of life (P<.02); in the diabetic group, the glucose level was reduced (P<.001). Compared with those in the UCD group, participants with hypertension/dyslipidemia in the prepared meal plan group showed greater improvements in total (P<.01) and high-density lipoprotein (P<.03) cholesterol levels, systolic blood pressure (P<.03), and glucose level (P<.03); in participants with type 2 diabetes mellitus, there were greater improvements in glucose (P =.046) and glycosylated hemoglobin (P<.02) levels. The prepared meal plan group also showed greater improvements in quality of life (P<.05) and compliance (P<.001) than the UCD group. CONCLUSIONS: Long-term dietary interventions induced significant weight loss and improved cardiovascular risk in high-risk patients. The prepared meal plan simultaneously provided the simplicity and nutrient composition necessary to maintain long-term compliance and to reduce cardiovascular risk.

Adult↗
PubMed2000

Users' guides to the medical literature: XX. Integrating research evidence with the care of the individual patient. Evidence-Based Medicine Working Group.

Clinicians can use research results to determine optimal care for an individual patient by using a patient's baseline risk estimate, clinical prediction guidelines that quantitate an individual patient's potential for benefit, and published articles. We propose that when clinicians are determining the likelihood that treatment will prevent the target event (at the expense of adverse events) in a patient that they also incorporate the patient's values. The 3 main elements to joint clinical decision making are disclosure of information about the risks and benefits of therapeutic alternatives, exploration of the patient's values about both the therapy and potential outcomes, and the actual decision. In addressing the patient's risk of adverse events without treatment and risk of harm with therapy, clinicians must recognize that patients are rarely identical to the average study patient. Differences between study participants and patients in real-world practice tend to be quantitative (differences in degree of risk of the outcome or responsiveness to therapy) rather than qualitative (no risk or adverse response to therapy). The number needed to treat and number needed to harm can be used to generate patient-specific estimates relative to the risk of the outcome event. Clinicians must consider a patient's risk of adverse events from any intervention and incorporate the patient's values in clinical decision making by using information about the risks and benefits of therapeutic alternatives. JAMA. 2000;283:2829-2836

Decision Making↗
PubMed2000

Interventions for helping patients to follow prescriptions for medications.

BACKGROUND BACKGROUND: Efforts to assist patients with adherence to prescribed, self-administered medications might improve the benefits and efficiency of health care. OBJECTIVES OBJECTIVE: To update an ongoing review summarising the results of randomised controlled trials (RCTs) of interventions to help patients follow prescriptions for medications, focusing on trials that measured both adherence and clinical outcomes. SEARCH STRATEGY: Computerised searches to July 1998 in MEDLINE, CINAHL, The Cochrane Library, International Pharmaceutical Abstracts (IPA), PsychInfo, Sociofile, and HSTAR; bibliographies in articles on patient adherence; articles in the reviewers' personal collections; and contact with authors. SELECTION CRITERIA: Articles were selected if they reported an unconfounded RCT of an intervention to improve adherence with prescribed medications, measuring both medication adherence and treatment outcome, with at least 80% follow-up of each group studied and, for long-term treatments, at least six months follow-up for studies with positive initial findings. DATA COLLECTION AND ANALYSIS: Information on study design features, interventions and controls, and findings were extracted by one reviewer (PM) and a research assistant and confirmed by two of the other reviewers. The studies were too disparate to warrant meta-analysis. MAIN RESULTS: For short-term treatments, one study, of counselling and written information, showed an effect on adherence and clinical outcome. Ten of 19 interventions for long-term treatments reported in 17 RCTs were associated with improvements in adherence, but only nine interventions led to improvements in treatment outcomes. Almost all of the interventions that were effective for long-term care were complex, including combinations of more convenient care, information, counselling, reminders, self-monitoring, reinforcement, family therapy, and other forms of additional supervision or attention. Even the most effective interventions did not lead to large improvements in adherence and treatment outcomes. Two studies showed that telling patients about adverse effects of treatment did not affect their adherence. REVIEWER'S CONCLUSIONS: The full benefits of medications cannot be realised at currently achievable levels of adherence. Current methods of improving adherence for chronic health problems are mostly complex and not very effective. More studies of innovative approaches to assist patients to follow medication prescriptions are needed.

Drug Prescriptions↗
PubMed2000

Local opinion leaders: effects on professional practice and health care outcomes.

BACKGROUND: Both the theory of diffusion of innovations and the social influences model of behaviour change suggest that using local opinion leaders to transmit norms and model appropriate behaviour may improve health professional practice. OBJECTIVES: To assess the effects using local opinion leaders on the practice of health professionals or patient outcomes. SEARCH STRATEGY: We searched MEDLINE to May 1998, the Research and Development Resource Base in Continuing Medical Education, and reference lists of related systematic reviews and articles. SELECTION CRITERIA: Randomised trials of the use of local opinion leaders (defined as health professionals nominated by their colleagues as being educationally influential). The participants were health care professionals responsible for patient care. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Eight studies were included involving more than 296 health professionals. A variety of patient problems were targeted, including acute myocardial infarction, cancer pain, osteoarthritis, rheumatoid arthritis, chronic lung disease, vaginal birth after caesarean section, labour and delivery, and urinary catheter care. Six of seven trials that measured health professional practice demonstrated some improvement for at least one outcome variable, and in two trials, the results were statistically significant and clinically important. In three trials that measured patient outcomes, only one achieved an impact upon practice that was of practical importance: local opinion leaders were effective in improving the rate of vaginal birth after previous caesarean section. REVIEWER'S CONCLUSIONS: Using local opinion leaders results in mixed effects on professional practice. However, it is not always clear what local opinion leaders do and replicable descriptions are needed. Further research is required to determine if opinion leaders can be identified and in which circumstances they are likely to influence the practice of their peers.

Health Services Research↗
PubMed2000

Audit and feedback: effects on professional practice and health care outcomes.

BACKGROUND: Audit and feedback has been identified as having the potential to change the practice of health care professionals. OBJECTIVES: To assess the effects of audit and feedback on the practice of health professionals and patient outcomes. SEARCH STRATEGY: We searched MEDLINE up to June 1997, the Research and Development Resource Base in Continuing Medical Education, and reference lists of related systematic reviews and articles. SELECTION CRITERIA: Randomised trials of audit and feedback (defined as any summary of clinical performance of health care over a specified period of time). The participants were health care professionals responsible for patient care. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Thirty-seven studies were included, involving more than 4977 physicians. The reporting of study methods was inadequate for almost all studies. In 31 out of 37 studies the randomisation process could not be determined. Information regarding data analysis was also lacking. For example, power calculations were not mentioned in 27 out of 37 studies. A variety of behaviours were targeted including the reduction of diagnostic test ordering, prescribing practices, preventive care, and the general management of a problem, for example hypertension. Twenty-eight studies measured physician performance, one study targeted patient outcomes in diabetes and the remaining eight studies measured both physician performance and patient outcomes. The relative percentage differences ranged from -16% to 152%. The clinical importance of the changes was not always clear. REVIEWER'S CONCLUSIONS: Audit and feedback can sometimes be effective in improving the practice of health care professionals, in particular prescribing and diagnostic test ordering. When it is effective, the effects appear to be small to moderate but potentially worthwhile. Those attempting to enhance professional behaviour should not rely solely on this approach.

Education, Medical, Continuing↗
PubMed2000

Audit and feedback versus alternative strategies: effects on professional practice and health care outcomes.

BACKGROUND: Audit and feedback has been identified as having the potential to change the practice of health care professionals. OBJECTIVES: To assess the effects of audit and feedback compared with other interventions in changing health professional practice and to assess whether the effectiveness of audit and feedback can be improved by modifying how it is done. SEARCH STRATEGY: We searched MEDLINE up to June 1997, the Research and Development Resource Base in Continuing Medical Education, and reference lists of related systematic reviews and articles. SELECTION CRITERIA: Randomised trials of audit and feedback (defined as any summary of clinical performance of health care over a specified period of time) compared with other interventions. The participants were health care providers responsible for patient care. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Twelve studies were included involving more than 2194 physicians. Seven trials with direct comparisons were included. The targeted behaviours were the management of low haemoglobin, the delivery of preventive care services (two studies), the management of high cholesterol, the performance of cervical smears, and the ordering of diagnostic tests (two studies). From the results of four trials, there is little evidence of a measurable effect of adding a complementary intervention such as a local consensus process to audit and feedback compared to audit and feedback alone. Two of three trials that compared audit and feedback to reminders reported that reminders were more effective in improving the delivery of some preventive services. REVIEWER'S CONCLUSIONS: It is not possible to recommend a complementary intervention to enhance the effectiveness of audit and feedback. Reminders might be more effective than audit and feedback to improve the delivery of some preventive services but the results are not striking. Few trials have investigated the effect of varying different characteristics of the audit and feedback process. Consideration should be given to testing the effects of modifying important characteristics such as the content, source, timing, recipient and format.

Education, Medical, Continuing↗
PubMed2000

Educational outreach visits: effects on professional practice and health care outcomes.

BACKGROUND: Outreach visits have been identified as an intervention that may improve the practice of health care professionals, in particular prescribing. This type of 'face to face' visit has been referred to as university-based educational detailing, public interest detailing, and academic detailing. OBJECTIVES: To assess the effects of outreach visits on improving health professional practice or patient outcomes. SEARCH STRATEGY: We searched MEDLINE up to March 1997, the Research and Development Resource Base in Continuing Medical Education, and reference lists of related systematic reviews and articles. SELECTION CRITERIA: Randomised trials of outreach visits (defined as a personal visit by a trained person to a health care provider in his or her own setting). The participants were health care professionals. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Eighteen studies were included involving more than 1896 physicians. All of the outreach visit interventions consisted of several components, including written materials and conferences. Reminders or audit and feedback complemented some visits. In 13 studies, the targeted behaviours were prescribing practices. In three studies, the behaviours were preventive services, including counselling for smoking cessation. In two studies, the outreach visits were directed toward improving the general management of common problems encountered in general practice, including asthma, diabetes, otitis media, hypertension, anxiety, and acute bronchitis. All studies examined physician behaviour and in three studies other health professionals such as nurses, nursing home attendants or health care workers were targeted. Positive effects on practice were observed in all studies. Only one study measured a patient outcome. Few studies examined the cost effectiveness of outreach. REVIEWER'S CONCLUSIONS: Educational outreach visits, particularly when combined with social marketing, appear to be a promising approach to modifying health professional behaviour, especially prescribing. Further research is needed to assess the effects of outreach visits for other aspects of practice and to identify key characteristics of outreach visits that are important to its success. The cost-effectiveness of outreach visits is not well evaluated.

Education, Medical, Continuing↗
PubMed2000

Carotid endarterectomy for symptomatic carotid stenosis.

BACKGROUND: Severe narrowing (or stenosis) of the carotid artery is an important cause of stroke. Surgical removal of the atheromatous material from the inside of the carotid artery (endarterectomy) may reduce the risk of stroke, but carries a risk of operative complications. OBJECTIVES: This review seeks to summarize the evidence from randomized trials on the balance of risks and benefits of carotid endarterectomy in adults with symptomatic carotid stenosis. SEARCH STRATEGY: We searched the Cochrane Stroke Group's Specialized Register of trials (date last searched: March 1999), supplemented by electronic searches of several databases. SELECTION CRITERIA: Randomized controlled trials comparing 'best medical treatment plus carotid endarterectomy' with 'best medical therapy' in patients with carotid stenosis and a recent transient ischaemic attack or nondisabling ischaemic stroke in the territory of that artery. DATA COLLECTION AND ANALYSIS: Two reviewers independently selected the studies and extracted the data. An intention to treat analysis was performed. MAIN RESULTS: Data on death or disabling stroke were available from two trials, which included 5950 patients: the North American Symptomatic Carotid Endarterectomy Trial (NASCET), and the European Carotid Surgery Trial (ECST). The two trials used different methods to measure stenosis, but a simple formula can be used to convert between the two methods. For patients with severe stenosis (ECST > 80% = NASCET > 70%), surgery reduced the relative risk of disabling stroke or death by 48% (95% confidence interval [CI] 27 - 73%). The number of patients needed to be operated on (number needed to treat [NNT]) to prevent one disabling stroke or death over 2 to 6 years follow-up was 15 (95% CI 10 - 31). For patients with less severe stenosis (ECST 70 - 79% = NASCET 50 - 69%), surgery reduced the relative risk of disabling stroke or death by 27% (95% CI 15 - 44%). The number of patients needed to be operated on to prevent one disabling stroke or death was 21 (95% CI 11 - 125). Patients with lesser degrees of stenosis were harmed by surgery. Surgery increased the risk of disabling stroke or death by 20% (95% CI 0 - 44%). The number of patients needed to be operated on to cause one disabling stroke or death was 45 (95% CI 22 - infinity). REVIEWER'S CONCLUSIONS: Carotid endarterectomy reduced the risk of disabling stroke or death for patients with stenosis exceeding ECST-measured 70% or NASCET-measured 50%. This result is generalizable only to surgically-fit patients operated on by surgeons with low complication rates (less than 6%).

Adult↗
PubMed2000

How to read a systematic review.

A systematic review is a carefully planned and conducted study designed to answer a specific focused clinical question. A systematic review differs from the frequently encountered narrative review article. Systematic review must be completed using a prespecified methodology. The reader must ask eight important questions when reading a systematic review: (i) did the review address a focused clinical question (ii) is it likely that important, relevant studies are missed (iii) were the inclusion criteria used to select appropriate articles (iv) was the validity of the included studies assessed (v) were the assessments of studies reproducible (vi) were the results similar from study to study (vii) what were the overall results and how precise are they and (viii) will the results help in caring for patients. The article also provides sources for systematic reviews.

Evidence-Based Medicine↗
PubMed2000

Factors affecting blood pressure responses to diet: the Vanguard study.

To study physiologic factors affecting the blood pressure (BP) response to nonpharmacologic maneuvers, fasting blood glucose, insulin, lipid and mineral levels, urinary mineral excretion, and the calcium regulating hormones parathyroid hormone (PTH) and 1,25 dihydroxyvitamin D (1,25 (OH)2D) were measured in 71 unmedicated hypertensive (26 hypertensive only [HT], 45 hypertensive hyperlipidemic [HTHL]), and 87 normotensive hyperlipidemic (NTHL) control subjects before and during a 10-week multicenter, randomized controlled trial comparing a prepared meal plan (CCNW) with a self-selected diet (SSD) based on nutritionist counseling. Blood pressure fell to a greater extent in hypertensive versus normotensive subjects (-8+/-1/-5+/-1 v -2+/-1/-2+/-1 mm Hg, P < .0001/P < .0001), and on CCNW versus SSD diets (delta systolic BP [SBP]/delta diastolic BP [DBP], P = .033/P = .002). Diet-induced weight change was the strongest correlate of changes in BP (SBP: r = 0.360, P < .0001; DBP: r = 0.414, P < .0001), which, on multivariate analysis for deltaSBP, could partly be accounted for by diet-induced changes in fasting glucose (r = 0.215, P = .009) and cholesterol (r = 0.219, P = .006) levels. Independently of weight, diet-induced changes in SBP also were significantly related to concomitant changes in urinary excretion of potassium (r = -0.285, P = .001), magnesium (r = -0.254, P = .003), and calcium relative to sodium (r = -0.200, P = .021), but not to sodium per se; and to changes in serum potassium (r = -0.249, P = .002), phosphorus (r = -0.279, P = .001), PTH (r = 0.288, P = .0006), and 1,25 D (r = 0.202, P = .017). We conclude that the ability of diet to lower BP successfully may result from the additive contributions of multiple components. Independently of weight loss and the associated changes in circulating glucose and cholesterol, BP is influenced by the increasing provision of minerals such as potassium, magnesium, and calcium, perhaps by virtue of their suppressive effects on circulating vasoactive calcium regulating hormones.

Adult↗
PubMed1999

Low-dose and high-dose acetylsalicylic acid for patients undergoing carotid endarterectomy: a randomised controlled trial. ASA and Carotid Endarterectomy (ACE) Trial Collaborators.

BACKGROUND: Endarterectomy benefits certain patients with carotid stenosis, but benefits are lessened by perioperative surgical risk. Acetylsalicylic acid lowers the risk of stroke in patients who have experienced transient ischaemic attack and stroke. We investigated appropriate doses and the role of acetylsalicylic acid in patients undergoing carotid endarterectomy. METHODS: In a randomised, double-blind, controlled trial, 2849 patients scheduled for endarterectomy were randomly assigned 81 mg (n=709), 325 mg (n=708), 650 mg (n=715), or 1300 mg (n=717) acetylsalicylic acid daily, started before surgery and continued for 3 months. We recorded occurrences of stroke, myocardial infarction, and death. We compared patients on the two higher doses of acetylsalicylic acid with patients on the two lower doses. FINDINGS: Surgery was cancelled in 45 patients, none were lost to follow-up by 30 days, and two were lost by 3 months. The combined rate of stroke, myocardial infarction, and death was lower in the low-dose groups than in the high-dose groups at 30 days (5.4 vs 7.0%, p=0.07) and at 3 months (6.2 vs 8.4%, p=0.03). In an efficacy analysis, which excluded patients taking 650 mg or more acetylsalicylic acid before randomisation, and patients randomised within 1 day of surgery, combined rates were 3.7% and 8.2%, respectively, at 30 days (p=0.002) and 4.2% and 10.0% at 3 months (p=0.0002). INTERPRETATION: The risk of stroke, myocardial infarction, and death within 30 days and 3 months of endarterectomy is lower for patients taking 81 mg or 325 mg acetylsalicylic acid daily than for those taking 650 mg or 1300 mg.

Aged↗
PubMed1999

Nutritionally complete prepared meal plan to reduce cardiovascular risk factors: a randomized clinical trial.

OBJECTIVE: To compare a nutritionally complete prepared meal plan that meets national dietary guidelines to usual-care dietary therapy for hypertension, dyslipidemia, and glycemic control. DESIGN: Randomized, controlled trial. SUBJECTS/SETTING: Outpatients with hypertension, dyslipidemia, or diabetes mellitus (n = 251) were recruited at 6 medical centers in the United States and Canada. INTERVENTION: The prepared meal plan, which was developed by university-based nutrition and cardiovascular scientists and food technologists at Campbell's Center for Nutrition & Wellness (CCNW), provided the optimal levels of macronutrients and micronutrients recommended for cardiovascular risk reduction in a variety of prepackaged meals and snacks. After a 4-week pretrial period to assess baseline state, participants were randomized to the CCNW plan or "usual-care" diet for 10 weeks. MAIN OUTCOME MEASURES: Blood pressure, carbohydrate metabolism, lipoproteins, homocysteine, weight, nutrient intake, compliance. STATISTICAL ANALYSES PERFORMED: Repeated measures analysis of variance. RESULTS: Lipoproteins, carbohydrate metabolism, blood pressure, and weight improved on both plans. Mean differences (+/- standard deviation) between baseline and follow-up for the CCNW plan and the usual-care plan, respectively, were total cholesterol, -0.41 +/- 0.64 and -0.20 +/- 0.50 mmol/L (between-group P < .01); plasma glucose, -0.7 +/- 1.7 and -0.3 +/- 1.3 mmol/L (P < .05); systolic blood pressure, -5.2 +/- 10.0 and -4.7 +/- 9.0 mm Hg (P = .67), diastolic blood pressure, -3.8 +/- 5.9 and -2.2 +/- 5.5 mm Hg (P < .05); and homocysteine, -1.3 +/- 3.8 and 0.2 +/- 3.4 mumol/L (P < .01). The CCNW plan led to greater weight loss than the usual-care diet (-5.5 +/- 3.8 kg vs -3.0 +/- 3.2 kg, P < .0001). APPLICATIONS/CONCLUSION: The nutritionally complete CCNW plan offers greater improvements in lipids, blood sugars, homocysteine, and weight loss than usual-care diet therapy. This prepackaged comprehensive nutrition program can augment both the prescription and practice of optimal dietary therapy.

Adult↗
PubMed1999

Canadian hypertension society guidelines for ambulatory blood pressure monitoring.

The Canadian Hypertension Society has developed guidelines for the use of ambulatory blood pressure (BP) monitoring in clinical practice. Published articles with the best available levels of evidence were used to support the following recommendations: Physicians should only use ambulatory BP monitoring devices that have been validated independently using established protocols. A decision to withhold drug therapy based upon the ambulatory BP should take into account normal values for 24-h and awake ambulatory BP. Based upon studies on prognosis and a clinical trial based upon BP control as an outcome, ambulatory BP monitoring should be considered for untreated patients whenever an office-induced increase in BP is suspected. Ambulatory BP monitoring should be considered for treated patients suspected of having an office-induced increase in BP, including individuals with apparent resistance to drug therapy, symptoms suggestive of hypotension, and fluctuating office BP readings. Based upon studies on prognosis, changes in nocturnal BP should be taken into account in any decision to withhold drug therapy based upon the ambulatory BP. Further studies are required to determine whether the clinical benefit of antihypertensive therapy is more closely related to ambulatory or office BP.

Blood Pressure↗