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PubMedDate not supplied

Improving test ordering in primary care: the added value of a small-group quality improvement strategy compared with classic feedback only.

PURPOSE: We wanted to evaluate the added value of small peer-group quality improvement meetings compared with simple feedback as a strategy to improve test-ordering behavior. Numbers of tests ordered by primary care physicians are increasing, and many of these tests seem to be unnecessary according to established, evidence-based guidelines. METHODS: We enrolled 194 primary care physicians from 27 local primary care practice groups in 5 health care regions (5 diagnostic centers). The study was a cluster randomized trial with randomization at the local physician group level. We evaluated an innovative, multifaceted strategy, combining written comparative feedback, group education on national guidelines, and social influence by peers in quality improvement sessions in small groups. The strategy was aimed at 3 specific clinical topics: cardiovascular issues, upper abdominal complaints, and lower abdominal complaints. The mean number of tests per physician per 6 months at baseline and the physicians' region were used as independent variables, and the mean number of tests per physician per 6 months was the dependent variable. RESULTS: The new strategy was executed in 13 primary care groups, whereas 14 groups received feedback only. For all 3 clinical topics, the decrease in mean total number of tests ordered by physicians in the intervention arm was far more substantial (on average 51 fewer tests per physician per half-year) than the decrease in mean number of tests ordered by physicians in the feedback arm (P = .005). Five tests considered to be inappropriate for the clinical problem of upper abdominal complaints decreased in the intervention arm, with physicians in the feedback arm ordering 13 more tests per 6 months (P = .002). Interdoctor variation in test ordering decreased more in the intervention arm. CONCLUSION: Compared with only disseminating comparative feedback reports to primary care physicians, the new strategy of involving peer interaction and social influence improved the physicians' test-ordering behavior. To be effective, feedback needs to be integrated in an interactive, educational environment.

Abdominal Pain↗
PubMed2004

A randomised controlled trial of a tailored multifaceted strategy to promote implementation of a clinical guideline on induced abortion care.

OBJECTIVE: To evaluate the effectiveness and efficiency of a tailored multifaceted strategy, delivered by a national clinical effectiveness programme, to implement a guideline on induced abortion. DESIGN: Cluster randomised controlled trial. SETTING AND PARTICIPANTS: All 26 hospital gynaecology units in Scotland providing induced abortion care. INTERVENTION: Following the identification of barriers to guideline implementation, intervention units received a package comprising audit and feedback, unit educational meetings, dissemination of structured case records and promotion of a patient information booklet. Control units received printed guideline summaries alone. MAIN OUTCOME MEASURES: Compliance with five key guideline recommendations (primary outcomes) and compliance with other recommendations, patient satisfaction and costs of the implementation strategy (secondary outcomes). RESULTS: No effect was observed for any key recommendation: appointment with a gynaecologist within five days of referral (odds ratio 0.89; 95% confidence interval 0.50 to 1.58); ascertainment of cervical cytology history (0.93; 0.36 to 2.40); antibiotic prophylaxis or screening for lower genital tract infection (1.70; 0.71 to 5.99); use of misoprostol as an alternative to gemeprost (1.00; 0.27 to 1.77); and offer of contraceptive supplies at discharge (1.11; 0.48 to 2.53). Median pre-intervention compliance was near optimal for antibiotic prophylaxis and misoprostol use. No intervention benefit was observed for any secondary outcome. The intervention costs an average of pound 2607 per gynaecology unit. CONCLUSIONS: The tailored multifaceted strategy was ineffective. This was possibly attributable to high pre-intervention compliance and the limited impact of the strategy on factors outside the perceived control of clinical staff.

Abortion, Induced↗
PubMed2006

Can antibiotic prescriptions in respiratory tract infections be improved? A cluster-randomized educational intervention in general practice--the Prescription Peer Academic Detailing (Rx-PAD) Study [NCT00272155].

BACKGROUND: More than half of all antibiotic prescriptions in general practice are issued for respiratory tract infections (RTIs), despite convincing evidence that many of these infections are caused by viruses. Frequent misuse of antimicrobial agents is of great global health concern, as we face an emerging worldwide threat of bacterial antibiotic resistance. There is an increasing need to identify determinants and patterns of antibiotic prescribing, in order to identify where clinical practice can be improved. METHODS/DESIGN: Approximately 80 peer continuing medical education (CME) groups in southern Norway will be recruited to a cluster randomized trial. Participating groups will be randomized either to an intervention- or a control group. A multifaceted intervention has been tailored, where key components are educational outreach visits to the CME-groups, work-shops, audit and feedback. Prescription Peer Academic Detailers (Rx-PADs), who are trained GPs, will conduct the educational outreach visits. During these visits, evidence-based recommendations of antibiotic prescriptions for RTIs will be presented and software will be handed out for installation in participants PCs, enabling collection of prescription data. These data will subsequently be linked to corresponding data from the Norwegian Prescription Database (NorPD). Individual feedback reports will be sent all participating GPs during and one year after the intervention. Main outcomes are baseline proportion of inappropriate antibiotic prescriptions for RTIs and change in prescription patterns compared to baseline one year after the initiation of the tailored pedagogic intervention. DISCUSSION: Improvement of prescription patterns in medical practice is a challenging task. A thorough evaluation of guidelines for antibiotic treatment in RTIs may impose important benefits, whereas inappropriate prescribing entails substantial costs, as well as undesirable consequences like development of antibiotic resistance. Our hypothesis is that an educational intervention program will be effective in improving prescription patterns by reducing the total number of antibiotic prescriptions, as well as reducing the amount of broad-spectrum antibiotics, with special emphasis on macrolides.

Anti-Bacterial Agents↗
PubMed2001

Partnerships, community participation and intersectoral collaboration in South Africa.

Five community partnerships (CP) were initiated in South Africa as demonstration projects aimed at the re-orientation of health professionals' education (HPE) to be more community responsive and interprofessional. A cluster evaluation of these partnerships has demonstrated that, in addition to motivating all stakeholders to forge closer working relationships, it is necessary for partnerships to pay close attention to a variety of structural and operational dimensions, the lack of which could prove to be major constraints to effective partnership functioning. This study critically reviews the challenges to collaborative working as experienced by the South African cluster. Within the context of the post-apartheid restructuring and development, the discussion highlights the insights that partnerships offer to clarify the extent to which potential barriers could affect the stakeholder groups. The paper identifies potential impediments, and makes explicit how they impact on partnership fostering. Evidence is also presented for their early detection and possible solutions are identified. The lessons learnt from these South African cases are that wide representation, commitment and a sense of ownership, sound leadership skills, regular and effective communication, reliable member expertise and capabilities and attention to power issues are crucial elements in the partnership equation. The paper concludes with an invitation to health administrators and partnership executives to devote attention to the array of interacting components that, collectively, could impinge on the effectiveness of the multifaceted nature of interprofessional joint working arrangements.

Cluster Analysis↗
PubMed2006

Outcomes of a multifaceted physical activity regimen as part of a diabetes self-management intervention.

BACKGROUND: Physical activity (PA) is important for management of diabetes, yet practical interventions that achieve sustained behavior change are rare. PURPOSE: The goals of this research were to evaluate the effectiveness of a multifaceted PA intervention for people with type 2 diabetes that emphasized participant choice in activity selection. Baseline activity patterns were examined to determine whether they predicted changes in PA at 2 months. METHODS: Three hundred thirty-five participants were recruited from 42 primary care physicians and then randomized to either a computer-assisted, tailored self-management intervention (N = 174) or health risk appraisal with feedback control (N = 161). Primary outcome measures included the Community Healthy Activities Model Program for Seniors Questionnaire, diet, and psychosocial assessments at baseline and 2 months. RESULTS: For 301 participants who completed the 2-month follow-up, the intervention significantly improved all PA (p < .01) and moderate PA (metabolic equivalents > 3.0, p < 01) relative to controls. Baseline cluster analyses grouped participant activity patterns into three categories. At 2 months, cluster assignment differentially predicted change in calories expended in moderate, rote, sport, and lifestyle PA. CONCLUSIONS: A computer-assisted, multifaceted approach to PA demonstrated improvement after 2 months. The results suggest that individuals are capable of adjusting their activity patterns to maximize their PA.

Choice Behavior↗
PubMed2003

The ERGO genome analysis and discovery system.

The ERGO (http://ergo.integratedgenomics.com/ERGO/) genome analysis and discovery suite is an integration of biological data from genomics, biochemistry, high-throughput expression profiling, genetics and peer-reviewed journals to achieve a comprehensive analysis of genes and genomes. Far beyond any conventional systems that facilitate functional assignments, ERGO combines pattern-based analysis with comparative genomics by visualizing genes within the context of regulation, expression profiling, phylogenetic clusters, fusion events, networked cellular pathways and chromosomal neighborhoods of other functionally related genes. The result of this multifaceted approach is to provide an extensively curated database of the largest available integration of genomes, with a vast collection of reconstructed cellular pathways spanning all domains of life. Although access to ERGO is provided only under subscription, it is already widely used by the academic community. The current version of the system integrates 500 genomes from all domains of life in various levels of completion, 403 of which are available for subscription.

Animals↗
PubMed2005

Effectiveness of clinical practice guideline implementation on lower third molar management in improving clinical decision-making: a randomized controlled trial.

The objective of this study was twofold, namely to evaluate the effectiveness of a dental clinical practice guideline on the management of asymptomatic impacted lower third molars (i) on referral rates and (ii) on dentists' change in knowledge. A two-arm cluster randomized controlled trial, with pre- and post-test assessments, was conducted. A guideline was implemented by multifaceted interventions (i.e. feedback, reminders, and an interactive meeting). The effect was evaluated after 1 yr by repeating the baseline questionnaire and by monitoring the number of patients who were referred for removal of their asymptomatic impacted mandibular third molars. Instruments were questionnaires for detecting changes in knowledge, patient records, and panoramic radiographs. The knowledge of dentists regarding asymptomatic mandibular third molar management was found to increase significantly in the intervention group as compared to the control group. There was no statistically significant difference between the groups in guideline-consistent patient referral rates at the post-test assessment. It was concluded that the methodology employed for dissemination and implementation of a clinical practice guideline on asymptomatic mandibular third molar management improves dentists' knowledge on this topic and is effective in improving decision-making in simulated cases; however, no clinical effect was demonstrated.

Communication↗
PubMed2005

[Effectiveness of a multifactorial strategy for implementing clinical guidelines on unstable angina: cluster randomized trial].

UNLABELLED: INTRODUCTION AND OBJECTIVES. Clinical practice in unstable angina is not always based on best evidence. Guidelines have the potential to improve quality of health care. There are no randomised trials assessing implementation strategies in the public healthcare system of Spain yet. OBJECTIVE: to compare the effectiveness of a multifaceted strategy (interactive educational meetings, local consensus process) for guideline implementation in unstable angina, with a passive dissemination strategy. Patients and method. SETTING: 10 wards from 3 university hospitals in Sevilla. PARTICIPANTS: 153 specialists (cardiologists, internists) and their patients admitted for an unstable angina episode. DESIGN: a pragmatic, before and after cluster randomized controlled trial. Intervention was delivered from January to April 1998. Retrospective data collection took place in July 1999, of those pre and post-intervention episodes attended from January to October 1997 and from September 1998 to June 1999, respectively. OUTCOMES: compliance with the guideline recommendations for coronary angiography and stress testing, and ejection fraction assessment. RESULTS: The multifaceted strategy compared with the passive one, was associated with an absolute improvement in the appropriateness of use of coronary angiography and stress testing of 11% (95% CI, 0.85-21.1), P=.03. There was no association for the assessment of the ejection fraction: absolute improvement of 1.1% (95% CI, --15.9 to 18.1), P=.88. CONCLUSIONS: Our results show that a combination of interactive educational meetings and local consensus process delivered to wards of physicians may improve the appropriateness of use of coronary angiography and stress testing.

Aged↗
PubMed1989

Adolphe Abrahams memorial lecture, 1988. Exercise and lifestyle change.

While the evidence for a clustering of health habits is not particularly strong, there are both pedagogic and economic arguments in favour of a multifaceted approach to health education. The present review thus examines the impact of regular physical exercise upon other forms of health behaviour, testing the extent to which an activity programme can be a catalyst of improved lifestyle in both primary and secondary preventive therapy. The conceptual framework of health promotion is examined with particular reference to the models of Skinner, Becker, Fishbein, Triandis and Rokeach. Certain differences are noted between the decision to exercise and the marketing decisions for which Fishbein's model was originally designed. Nevertheless, in its later modifications, it provides a basic framework for understanding how human lifestyle is shaped. Theoretical mechanisms are suggested whereby exercise could influence such behaviours as cigarette smoking, alcohol consumption and drug usage, seat-belt usage, hypertension, body mass, lipid profile, promiscuous sexual behaviour, the carrying of lethal weapons, and acceptance of regular preventive medical examinations. The empirical evidence from both cross-sectional and longitudinal experiments shows a relatively weak association between exercise habits and other desirable forms of health behaviour. Moreover, it is arguable that other forms of health intervention such as smoking withdrawal or dieting might be equally effective as a primary change agent, and much of the observed association between exercise and other health habits could be attributable to a common dependence on demographic and socio-economic factors. On the other hand, the apparent weakness of associations may arise in part from difficulties in measuring both habitual physical activity and other forms of health behaviour, with a resultant attenuation of correlations. Possibly, a stronger association between exercise participation and other favourable health habits would be uncovered if attention were focused upon those forms of endurance exercise currently thought to enhance cardiac health. Given that moderate endurance exercise is also positive and pleasant advice, further examination of the potential of multifaceted but exercise-centered health promotion programmes appears warranted.

Exercise↗
PubMed2003

Identification of nutrient partitioning genes participating in rice grain filling by singular value decomposition (SVD) of genome expression data.

BACKGROUND: In order to identify rice genes involved in nutrient partitioning, microarray experiments have been done to quantify genomic scale gene expression. Genes involved in nutrient partitioning, specifically grain filling, will be used to identify other co-regulated genes, and DNA binding proteins. Proper identification of the initial set of bait genes used for further investigation is critical. Hierarchical clustering is useful for grouping genes with similar expression profiles, but decreases in utility as data complexity and systematic noise increases. Also, its rigid classification of genes is not consistent with our belief that some genes exhibit multifaceted, context dependent regulation. RESULTS: Singular value decomposition (SVD) of microarray data was investigated as a method to complement current techniques for gene expression pattern recognition. SVD's usefulness, in finding likely participants in grain filling, was measured by comparison with results obtained previously via clustering. 84 percent of these known grain-filling genes were re-identified after detailed SVD analysis. An additional set of 28 genes exhibited a stronger grain-filling pattern than those grain-filling genes that were unselected. They also had upstream sequence containing motifs over-represented among grain filling genes. CONCLUSIONS: The pattern-based perspective that SVD provides complements to widely used clustering methods. The singular vectors provide information about patterns that exist in the data. Other aspects of the decomposition indicate the extent to which a gene exhibits a pattern similar to those provided by the singular vectors. Thus, once a set of interesting patterns has been identified, genes can be ranked by their relationship with said patterns.

Cluster Analysis↗
PubMed2004

The emergency department community-acquired pneumonia trial: Methodology of a quality improvement intervention.

Community-acquired pneumonia causes more than 4 million episodes of illness each year and has high morbidity, mortality, and total cost of care. Nationwide, nearly 75% of community-acquired pneumonia patients are initially evaluated and treated in hospital-based emergency departments (EDs). Substantial variation exists in illness severity assessment, hospital admission decisions, and performance of recommended processes of care. We designed an ED-based quality improvement trial focused on the initial care of patients with community-acquired pneumonia. We used the Pneumonia Severity Index and level of arterial oxygenation to identify patients at low risk for 30-day mortality and to guide admission decisionmaking. We assessed the performance of recommended "best practices," consisting of assessment of arterial oxygenation, the collection of blood cultures for inpatients, and the timely initiation of appropriate empiric antibiotic therapy for inpatients and outpatients. We conducted a 32-site, cluster-randomized trial in Pennsylvania and Connecticut, comparing the effectiveness and safety of 3 guideline implementation strategies of increasing intensity. The multifaceted implementation plans were carried out in conjunction with each state's quality improvement organization. This article describes the background, objectives, and methodology of this trial to translate evidence-based knowledge on the quality and efficiency of care for community-acquired pneumonia into clinical practice.

Anti-Bacterial Agents↗
PubMed2004

Effects of training in direct observation of medical residents' clinical competence: a randomized trial.

BACKGROUND: Faculty observation of residents and students performing clinical skills is essential for reliable and valid evaluation of trainees. OBJECTIVE: To evaluate the efficacy of a new multifaceted method of faculty development called direct observation of competence training. DESIGN: Controlled trial of faculty from 16 internal medicine residency programs using a cluster randomization design. SETTING: Academic medical centers. PARTICIPANTS: 40 internal medicine teaching faculty members: 17 in the intervention group and 23 in the control group. MEASUREMENTS: Changes in faculty comfort performing direct observation, faculty satisfaction with workshop, and changes in faculty rating behaviors 8 months after completing the training. INTERVENTION: The direct observation of competence workshop combines didactic mini-lectures, interactive small group and videotape evaluation exercises, and evaluation skill practice with standardized residents and patients. RESULTS: 37 faculty members (16 in the intervention group and 21 in the control group) completed the study. Most of the faculty in the intervention group (14 [88%]) reported that they felt significantly more comfortable performing direct observation compared with control group faculty (4 [19%]) (P = 0.04), and all intervention faculty rated the training as outstanding. For 9 videotaped clinical encounters, intervention group faculty were more stringent than controls in their evaluations of medical interviewing, physical examination, and counseling; differences in ratings for medical interviewing and physical examination remained statistically significant even after adjustment for baseline rating behavior. LIMITATIONS: The study involved a limited number of residency programs, and faculty did not rate the performance of actual residents. CONCLUSION: Direct observation of competence training, a new multifaceted approach to faculty development, leads to meaningful changes in rating behaviors and in faculty comfort with evaluation of clinical skills.

Adult↗
PubMed2003

Randomised trial of intensive academic detailing to promote opportunistic recruitment of women to cervical screening by general practitioners.

OBJECTIVE: To evaluate a multifaceted intervention involving intensive academic detailing for general practitioners (GPs) to improve recruitment of women for cervical screening. METHODS: We conducted a cluster randomisation trial involving 39 general practices in inner-metropolitan Sydney. GPs' knowledge, propensity to an opportunistic approach, competence and confidence were assessed by self-report before and after the intervention. To measure GP behaviour, recall of an opportunistic discussion about cervical screening was determined in cross-sectional samples of female patients at baseline (n = 1,090) and post-test (n = 1,062). RESULTS: Knowledge improved marginally in both groups but there were no changes in other GP self-reported measures. At post-test, women attending GPs in the intervention group were no more likely than those in the control group to recall an opportunistic inquiry about their cervical screening status (OR 0.65, 95% CI 0.40-1.08). Women in the intervention group who were overdue for cervical screening were no more likely than their control group counterparts at post-test to recall advice about cervical screening (OR 2.16, 95% CI 0.75-6.14) or written information (OR 0.34, 95% CI 0.04-26.5). CONCLUSIONS: Intensive academic detailing does not improve an opportunistic approach to cervical screening in general practice. IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: In an evidence-based climate, implementation of academic detailing as a strategy to improve cervical screening rates in general practice would be premature.

Adult↗
PubMed2001

Genomic expression analysis implicates Wnt signaling pathway and extracellular matrix alterations in hepatic specification and differentiation of murine hepatic stem cells.

HBC-3 hepatic stem cells maintained in the undifferentiated state can be induced to differentiate along the hepatocyte lineage in response to DMSO (Rogler, 1997). In order to understand the complex transcriptional regulatory mechanisms associated with the differentiation of these somatic stem cells and to identify novel candidate stem cell and differentiation associated genes, we have begun to characterize the transcriptome of HBC-3 cells during a 7-day differentiation protocol. This analysis showed that differentiating HBC-3 cells undergo biphasic bursts of gene regulation peaking at 3 hours and 120 hours of DMSO treatment. In the undifferentiated state, HBC-3 cells express muscle, neuron, myeloid, and lymphoid specific genes that are rapidly downregulated during hepatocytic differentiation. Cluster analysis has revealed large groups of genes with different temporal regulation profiles demonstrating complex and widespread transcriptional changes. Specifically, we discovered a multifaceted downregulation of the Wnt/beta-catenin pathway accompanied by the repression of TCF target genes during HBC-3 differentiation. In addition, there is downregulation of cellular receptors for fibronectin and laminin and other extracellular matrix molecules indicative of widespread cell surface alterations. DMSO induces cell cycle arrest, and this is reflected in upregulation of growth inhibitory proteins such as cyclin I and p18 and downregulation of cyclins B1 and D. Genes needed for hepatocytic functions, such as apolipoprotein C-IV, phosphoenolpyruvate carboxykinase, alcohol dehydrogenase, and asialoglycoprotein receptor were upregulated. Finally, transcriptional regulators including Twist, Snail, HNF1a, and GATA6 were upregulated during differentiation of HBC-3 cells. The significance of these findings is that our genome-based approach has allowed the parallel identification of multiple regulatory pathways that is needed to begin to fully understand the complex differentiation process.

Animals↗
PubMed2002

Distinct gene expression signatures in the striata of wild-type and heterozygous c-fos knockout mice following methamphetamine administration: evidence from cDNA array analyses.

Methamphetamine (METH) is a drug of abuse which can cause apoptosis and degeneration of monoaminergic terminals in the mammalian brain. c-fos appears to play a protective role against METH-induced damage because METH toxicity is exacerbated in c-fos heterozygous knockout mice. In the present study, we used the comprehensive technique of cDNA array to test the idea that heterozygous c-fos knockout mice might show differential METH-induced molecular responses in comparison to wild-type (WT) animals. Of 1,176 genes examined, the expression of 195 genes in either of the two groups of mice was affected by at least 2-fold at 2 or 12 h after METH treatment. More genes were either up- or downregulated in the WT mice. Moreover, there were substantial differences in the pattern of responses between the two genotypes, with more genes involved in DNA repair and protective processes being upregulated in WT mice after METH administration. These results support the idea that the c-fos knockout genotype may render the animals unable to trigger multicomponent responses in order to protect against the multifaceted toxic effects of this illicit neurotoxin.

Animals↗
PubMed2002

Multifaceted support to improve clinical decision making in diabetes care: a randomized controlled trial in general practice.

AIMS: To evaluate the effectiveness of a multifaceted intervention to improve the clinical decision making of general practitioners (GPs) for patients with diabetes. To identify practice characteristics which predict success. METHODS: Cluster randomized controlled trial with 124 practices and 185 GPs in The Netherlands. The intervention group received feedback reports and support from a facilitator; the control group received no special attention. Outcome measures were the compliance rates with evidence-based recommendations pertaining to discussion of body weight control, discussion of problems with medication, blood pressure measurement, foot examination, eye examination, initiating anti-diabetic medication or increasing the dosage in cases of uncontrolled blood glucose, and scheduling a follow-up appointment. RESULTS: The GPs reported on their clinical decision making in 1410 consultations with Type 2 diabetic patients at baseline and 1449 consultations after the intervention period. The intervention resulted in statistically significant improvement for two of the seven outcome measures: foot examination (odds ratio 1.68; 95% confidence interval 1.19-2.39) and eye examination (1.52; 1.07-2.16). Discussion of problems with medication showed a near significant trend towards increased benefit for the intervention group (1.52; 0.99-2.32). Practice characteristics were not found to be related to the success of the intervention. CONCLUSIONS: Feedback reports with support from facilitators appear to increase rates of foot examination and eye examination in general practice. Alternative interventions should be explored to improve the pursuit of metabolic control by GPs.

Adult↗
PubMed2002

The insulin resistance syndrome: mechanisms of clustering of cardiovascular risk.

For more than a decade, insulin resistance has been proposed as the key linking factor for the metabolic syndrome disease cluster of glucose intolerance, hypertension, dyslipidemia, obesity, and cardiovascular disease. Although most of the epidemiological, experimental, and clinical evidence still support the role of insulin resistance as an important component of this multifaceted syndrome, there is evidence amassing that a neurohormonal mechanism, including an endocrine role for adipocytes, probably plays a more fundamental role. This is supported by the strong associations between obesity, especially central adiposity, and all components of the metabolic syndrome, in contrast to the inconsistent relationships between blood pressure and markers of insulin resistance. However, much of the effect of visceral fat on cardiovascular risk factors is mediated through the metabolic actions of free fatty acids (FFA) on insulin resistance, thus resolving any obesity versus insulin resistance controversy. In addition to the roles of obesity and FFA in the development of insulin resistance syndrome, the high prevalence rates of this disease cluster among subjects from low socioeconomic groups as well as from developing countries have led to alternative hypotheses to better our understanding of the contributory roles of socioeconomic, in utero, and genetic factors in this syndrome. More recently, the pathogenetic roles of iron overload and liver dysfunction have also been re-examined. In this article, the various hypotheses which have been put forward to explain the diverse clinical manifestations of the metabolic or insulin resistance syndrome are summarized and put into perspective. While there is clinical and experimental evidence to support many of these independent pathways, alternative statistical methods such as factor analysis or structural equation modeling may be needed to unravel the complex nature of these interacting pathways. Finally, these hypotheses, if proven, will add new dimensions to our current strategies and emphasize the need to focus on behavioral and socioeconomic interventions in addition to the use of pharmacological therapy in our attempt to control this epidemic disease of modern societies.

Adipocytes↗
PubMed2005

Informed patient consent to participation in cluster randomized trials: an empirical exploration of trials in primary care.

Cluster randomized trials are increasingly common. Obtaining informed patient consent to participation in these trials raises practical challenges and ethical issues. The aims of this paper were to 1) develop a typology of interventions employed in cluster randomized trials in primary care; 2) assess whether the likelihood of seeking individual consent to participation varies by intervension type; 3) assess whether this likelihood has increased over time; 4) assess evidence for under reporting of consent procedures; 5) articulate reasons for not obtaining consent; and 6) make recommendations for future trial investigators. We collected data on trial interventions and consent procedures from reports of 152 recently published trials, and 47 unpublished trials. We develop a typology of interventions based on reasons for adopting a clustered design. We examine proportions seeking individual consent to participation among trials involving different types of intervention, in different periods, and among published and unpublished trials. Two-thirds of the trials had multifaceted interventions. Trials involving different types of intervention had different propensities to seek consent, largely because of practical obstacles to obtaining consent. Obtaining consent can compromise internal validity. More recent trials are no more likely to obtain consent than past trials. There was no evidence of under-reporting of consent procedures in publications. In conclusion, future trial investigators should consider both practical reasons and scientific arguments for not obtaining individual patient consent for all interventions in their trials. Where feasible, they should allow patients to opt out of the trial. Lay individuals should represent trial participants as part of the process of cluster consent to participation, and lay individuals could also be involved in considering ethical issues during trial planning. A more public debate may clarify the general acceptability of not obtaining consent in certain situations.

Biomedical Research↗