Alessandro Liberati

Bio: Alessandro Liberati is an academic researcher from University of Modena and Reggio Emilia. The author has contributed to research in topics: Breast cancer & Systematic review. The author has an hindex of 46, co-authored 144 publications receiving 167184 citations. Previous affiliations of Alessandro Liberati include Mario Negri Institute for Pharmacological Research & Cochrane Collaboration.

Randomized clinical trials on medical treatment of glaucoma. Are they appropriate to guide clinical practice

Abstract: • A systematic quantitative and qualitative overview of published randomized clinical trials was undertaken to assess the yield of medical treatment on the outcome of patients with primary open angle glaucoma. Reports of 102 randomized clinical trials were published between 1975 and 1991, totaling about 5000 patients. Only 16% (16/102) of the trials were, however, properly designed (ie, comparing an active treatment with a placebo-treated or untreated control group) to answer the question of whether any medical treatment can effectively cure patients with primary open angle glaucoma. Pooled analysis showed a moderate yet statistically significant reduction in mean intraocular pressure (−4.9 mm Hg; 95% confidence interval [Cl], −7.3 to −2.5 mm Hg); however, data on long-term visual field changes were available in only three randomized clinical trials, and their statistical combination failed to show a significant protective effect of active treatment (odds ratio, 0.75; 95% CI, 0.42 to 1.35). All of the remaining 86 randomized clinical trials looked at the effectiveness of one drug vs another in lowering intraocular pressure and were thus of no use in the overview. Practicing ophthalmologists should be aware that the effectiveness of pressure-lowering agents in the treatment of primary open angle glaucoma is still to be determined and that the vast majority of published trials are not appropriate to guide clinical practice. It is urgent to plan trials with end-point and follow-up duration that is fully relevant for the health of patients.

Practice Guidelines: Useful and Participative Method?: Survey of Italian Physicians by Professional Setting

Abstract: Background Professional setting might be a key determinant of physicians' attitudes toward practice guidelines, influencing the effect of their implementation. Because no previous surveys have specifically considered this aspect, we evaluated the perceived role and usefulness of guidelines, as well as barriers to and facilitators of their implementation, for hospital, primary care, and nonpracticing clinicians. Methods A 43-item self-administered questionnaire was sent to all National Health Service physicians in the province of Modena, Italy (593 primary care physicians, 1049 hospital physicians, and 149 nonpracticing clinicians), and 1199 (66.9%) responded. Opinions and attitudes were assessed using 5-point ordinal scales and an attitude measurement scale. Results were evaluated overall and by professional setting, sex, age, year of graduation, and academic background. Results Practice guidelines were generally perceived to be less useful than other sources of medical information (eg, personal experience, conferences, colleagues, articles, the Internet, and textbooks [pharmaceutical representatives were the exception]). Most physicians thought that guidelines are developed for cost-containment reasons and expressed concerns about their limited applicability to individual patients and local settings. Most respondents did not favor the involvement of health professionals other than physicians in guideline development and use and preferred nonmonetary incentives for their implementation. Answers to individual items and attitude scores varied significantly across professional settings. Primary care physicians showed, in general, the least favorable attitudes toward practice guidelines, toward nonphysicians participating in guideline development and use, and toward incentives for guideline users. Conclusions Physicians perceived practice guidelines as externally imposed and cost-containment tools rather than as decision-supporting tools. Regularly monitoring attitudes toward practice guidelines can be helpful to evaluate potential barriers to their adoption.

The role of attitudes, beliefs, and personal characteristics of Italian physicians in the surgical treatment of early breast cancer.

Abstract: The influence of Italian physicians' attitudes, beliefs, and personal characteristics on medical decision making is examined in the case of surgical treatment of early breast cancer. Responses to a mail survey of 657 physicians from different specialties were analyzed comparing doctors recommending a radical procedure (9%) to those preferring a conservative procedure for younger patients only (25%), and those considering conservative surgery the treatment of choice regardless of patients' age (66%). The findings suggest that the likelihood of physicians' preferring a conservative procedure is influenced by their specialty and the extent to which they feel that a patient should have a role in the treatment decision more than by differences in the beliefs of treatment outcomes. Only preferences of the small group indicating radical surgery as the sole admissible treatment can be accounted for by ignorance or distrust of results of recent trials. These findings suggest that other than scientific factors guid...

Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement

Abstract: David Moher and colleagues introduce PRISMA, an update of the QUOROM guidelines for reporting systematic reviews and meta-analyses

Preferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement.

Abstract: Systematic reviews and meta-analyses have become increasingly important in health care. Clinicians read them to keep up to date with their field,1,2 and they are often used as a starting point for developing clinical practice guidelines. Granting agencies may require a systematic review to ensure there is justification for further research,3 and some health care journals are moving in this direction.4 As with all research, the value of a systematic review depends on what was done, what was found, and the clarity of reporting. As with other publications, the reporting quality of systematic reviews varies, limiting readers' ability to assess the strengths and weaknesses of those reviews. Several early studies evaluated the quality of review reports. In 1987, Mulrow examined 50 review articles published in 4 leading medical journals in 1985 and 1986 and found that none met all 8 explicit scientific criteria, such as a quality assessment of included studies.5 In 1987, Sacks and colleagues6 evaluated the adequacy of reporting of 83 meta-analyses on 23 characteristics in 6 domains. Reporting was generally poor; between 1 and 14 characteristics were adequately reported (mean = 7.7; standard deviation = 2.7). A 1996 update of this study found little improvement.7 In 1996, to address the suboptimal reporting of meta-analyses, an international group developed a guidance called the QUOROM Statement (QUality Of Reporting Of Meta-analyses), which focused on the reporting of meta-analyses of randomized controlled trials.8 In this article, we summarize a revision of these guidelines, renamed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses), which have been updated to address several conceptual and practical advances in the science of systematic reviews (Box 1). Box 1 Conceptual issues in the evolution from QUOROM to PRISMA

Measuring inconsistency in meta-analyses

Abstract: Cochrane Reviews have recently started including the quantity I 2 to help readers assess the consistency of the results of studies in meta-analyses. What does this new quantity mean, and why is assessment of heterogeneity so important to clinical practice? Systematic reviews and meta-analyses can provide convincing and reliable evidence relevant to many aspects of medicine and health care.1 Their value is especially clear when the results of the studies they include show clinically important effects of similar magnitude. However, the conclusions are less clear when the included studies have differing results. In an attempt to establish whether studies are consistent, reports of meta-analyses commonly present a statistical test of heterogeneity. The test seeks to determine whether there are genuine differences underlying the results of the studies (heterogeneity), or whether the variation in findings is compatible with chance alone (homogeneity). However, the test is susceptible to the number of trials included in the meta-analysis. We have developed a new quantity, I 2, which we believe gives a better measure of the consistency between trials in a meta-analysis. Assessment of the consistency of effects across studies is an essential part of meta-analysis. Unless we know how consistent the results of studies are, we cannot determine the generalisability of the findings of the meta-analysis. Indeed, several hierarchical systems for grading evidence state that the results of studies must be consistent or homogeneous to obtain the highest grading.2–4 Tests for heterogeneity are commonly used to decide on methods for combining studies and for concluding consistency or inconsistency of findings.5 6 But what does the test achieve in practice, and how should the resulting P values be interpreted? A test for heterogeneity examines the null hypothesis that all studies are evaluating the same effect. The usual test statistic …