Michaela Eikermann

Overviews of reviews often have limited rigor: a systematic review

OBJECTIVE To examine published overviews of systematic reviews in terms of descriptive and methodological characteristics. STUDY DESIGN AND SETTING MEDLINE, Database of Abstracts of Reviews of Effects, the Cochrane Database of Systematic Reviews, and several Health Technology Assessment databases were searched for overviews of reviews up to February 2012. We extracted data from the methods and results sections of the included overviews. These data were analyzed descriptively as frequencies or medians and interquartile ranges. RESULTS We included 126 overviews of reviews. According to our sample, publication rates for overviews have risen in the last decade. The quality of the included reviews was systematically appraised in 64% of the overviews. The most commonly used assessment tools were the Overview Quality Assessment Questionnaire (26%), Assessment of Multiple Systematic Reviews (11%), and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (5%). Only three of 18 overviews restricted to Cochrane reviews in our sample performed a quality assessment. Strategies to deal with discordant reviews were reported in 5% of the overviews. Searches for additional primary studies were conducted in 5% of the overviews. CONCLUSION Overviews of reviews often lack methodological rigor. Methodological standards and reporting guidelines for overviews are needed to improve the quality of this new publication type.

State of Evidence on the Relationship between High-Volume Hospitals and Outcomes in Surgery: A Systematic Review of Systematic Reviews

presented at the annual meeting of the German S Medicine and Prevention (DGSMP), Essen, Germany, S and the annual meeting of the German Network for Research (DNVF), Dresden, Germany, September 2012. Received October 29, 2012; Revised December 20, 2 December 20, 2012. From the Institute for Research in Operative Medicine, Fa School of Medicine, Witten/Herdecke University, Cologne Correspondence address: Dawid Pieper, MPH, Institute Operative Medicine, Faculty of Health, School of Me Herdecke University, Ostmerheimer Str 200, Building Cologne, Germany. email: dawid.pieper@uni-wh.de a 2013 by the American College of Surgeons Published by Elsevier Inc. COLLECTIVE REVIEW State of Evidence on the Relationship between High-Volume Hospitals and Outcomes in Surgery: A Systematic Review of Systematic Reviews Dawid Pieper, MPH, Tim Mathes, MHE, Edmund Neugebauer, PhD, Michaela Eikermann, MD In particular in surgical disciplines, many studies have been published on the volumeeoutcomes relationship since Luft and colleagues explained their theory of it. A lot of empirical work has shown differences in patient outcomes between high-volume hospitals (HVH) and low-volume hospitals (LVH) in favor of HVH. Mortality and survival have been explored the most in this debate. According to theory, superior outcomes in HVH can be explained by their structural characteristics (eg, teaching status or ownership) and a higher degree of experience. From this, it follows that the volumee outcomes relationship is likely to be most eminent in high-risk, low-volume procedures, such as pancreatectomy or esophagectomy. To improve patient outcomes, policy makers introduced minimum hospital volumes for surgical procedures. Among other quality criteria, accredited institutions performing bariatric surgery for Medicare patients must perform at least 125 operations per year. The Leapfrog Group has recommended annual hospital volumes for several surgical procedures. The European Society of Mastology claims for at least 150 newly diagnosed cases of primary breast cancer per year in specialized breast units. In Germany, minimum hospital volumes have been established for elected procedures. Although there seems to be a lot of evidence on the volumeeoutcomes relationship for several surgical procedures, there has also been a lot of criticism on the methodological quality of studies. Including methodologically flawed studies in systematic reviews can introduce bias in results when study quality is ignored. ociety of Social eptember 2012 Health Services

Appraisal tools for clinical practice guidelines: a systematic review.

Introduction Clinical practice guidelines can improve healthcare processes and patient outcomes, but are often of low quality. Guideline appraisal tools aim to help potential guideline users in assessing guideline quality. We conducted a systematic review of publications describing guideline appraisal tools in order to identify and compare existing tools. Methods Among others we searched MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews from 1995 to May 2011 for relevant primary and secondary publications. We also handsearched the reference lists of relevant publications. On the basis of the available literature we firstly generated 34 items to be used in the comparison of appraisal tools and grouped them into thirteen quality dimensions. We then extracted formal characteristics as well as questions and statements of the appraisal tools and assigned them to the items. Results We identified 40 different appraisal tools. They covered between three and thirteen of the thirteen possible quality dimensions and between three and 29 of the possible 34 items. The main focus of the appraisal tools were the quality dimensions “evaluation of evidence” (mentioned in 35 tools; 88%), “presentation of guideline content” (34 tools; 85%), “transferability” (33 tools; 83%), “independence” (32 tools; 80%), “scope” (30 tools; 75%), and “information retrieval” (29 tools; 73%). The quality dimensions “consideration of different perspectives” and “dissemination, implementation and evaluation of the guideline” were covered by only twenty (50%) and eighteen tools (45%) respectively. Conclusions Most guideline appraisal tools assess whether the literature search and the evaluation, synthesis and presentation of the evidence in guidelines follow the principles of evidence-based medicine. Although conflicts of interest and norms and values of guideline developers, as well as patient involvement, affect the trustworthiness of guidelines, they are currently insufficiently considered. Greater focus should be placed on these issues in the further development of guideline appraisal tools.

Systematic review found AMSTAR, but not R(evised)-AMSTAR, to have good measurement properties.

OBJECTIVES To summarize all available evidence on measurement properties in terms of reliability, validity, and feasibility of the Assessment of Multiple Systematic Reviews (AMSTAR) tool, including R(evised)-AMSTAR. STUDY DESIGN AND SETTING MEDLINE, EMBASE, Psycinfo, and CINAHL were searched for studies containing information on measurement properties of the tools in October 2013. We extracted data on study characteristics and measurement properties. These data were analyzed following measurement criteria. RESULTS We included 13 studies, four of them were labeled as validation studies. Nine articles dealt with AMSTAR, two articles dealt with R-AMSTAR, and one article dealt with both instruments. In terms of interrater reliability, most items showed a substantial agreement (>0.6). The median intraclass correlation coefficient (ICC) for the overall score of AMSTAR was 0.83 (range 0.60-0.98), indicating a high agreement. In terms of validity, ICCs were very high with all but one ICC lower than 0.8 when the AMSTAR score was compared with scores from other tools. Scoring AMSTAR takes between 10 and 20 minutes. CONCLUSION AMSTAR seems to be reliable and valid. Further investigations for systematic reviews of other study designs than randomized controlled trials are needed. R-AMSTAR should be further investigated as evidence for its use is limited and its measurement properties have not been studied sufficiently. In general, test-retest reliability should be investigated in future studies.

Evidence-based clinical practice: Overview of threats to the validity of evidence and how to minimise them

Using the best quality of clinical research evidence is essential for choosing the right treatment for patients. How to identify the best research evidence is, however, difficult. In this narrative review we summarise these threats and describe how to minimise them. Pertinent literature was considered through literature searches combined with personal files. Treatments should generally not be chosen based only on evidence from observational studies or single randomised clinical trials. Systematic reviews with meta-analysis of all identifiable randomised clinical trials with Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessment represent the highest level of evidence. Even though systematic reviews are trust worthier than other types of evidence, all levels of the evidence hierarchy are under threats from systematic errors (bias); design errors (abuse of surrogate outcomes, composite outcomes, etc.); and random errors (play of chance). Clinical research infrastructures may help in providing larger and better conducted trials. Trial Sequential Analysis may help in deciding when there is sufficient evidence in meta-analyses. If threats to the validity of clinical research are carefully considered and minimised, research results will be more valid and this will benefit patients and heath care systems.

Adherence enhancing interventions for oral anticancer agents: A systematic review

BACKGROUND The use of oral anticancer agents has increased in the last decades. Adherence is a crucial factor for the success of oral anticancer agent therapy. However, many patients are non-adherent. OBJECTIVE The objective was to evaluate the effectiveness of adherence interventions in patients taking oral anticancer agents. METHODS A systematic literature search was performed in Medline and Embase. Titles and abstracts and in case of potential relevance, full-texts were assessed for eligibility according to the predefined inclusion criteria. The study quality was evaluated. Both process steps were carried out independently by two reviewers. Relevant data on study design, patients, interventions and results were extracted in standardized tables by one reviewer and checked by a second reviewer. RESULTS Six controlled studies were included. Only one study was randomized. The study quality was moderate to low. One study showed statistically significant results in favor of the adherence intervention, two studies showed a tendency in favor of the intervention, one study showed an inconsistent result depending on the adherence definition and one study showed almost identical adherence rates in both groups. One study showed a tendency in favor of the control group. CONCLUSIONS Although most of the interventions are not very effective, it appears that certain adherence enhancing interventions could have a promising effect. One crucial point is the consideration of the baseline adherence when choosing patients to avoid ceiling effects. The evidence is limited due to lack of sufficient studies and partly inconsistent results. Further high quality studies are needed.

Commentary: Europe needs a central, transparent, and evidence based regulation process for devices

Last September, the European Commission published proposals to update regulations for medical devices in order to improve patient safety.1 The proposals are being discussed by the European parliament where critical debate is being led by the Committee on Environment, Public Health and Food Safety. Medical devices range from bandages to life support machines, and manufacturers classify them into four risk categories from low (such as urine drainage bags) to high risk (such as drug eluting cardiac stents) according to EU rules.2 The risk associated with the device depends on the duration of contact with the body, invasiveness, and whether it has a local or a systemic effect. Medium and high risk devices must be certified by one of the notified bodies, organisations that are accredited to assess a product’s compliance with EU legislation (CE mark). At a …

Intravascular volume therapy in adults: Guidelines from the Association of the Scientific Medical Societies in Germany

Index Table of contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489 List of abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489 A. Rationale and goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 A1: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 A2: Initial situation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 A3: Guideline requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 A4: Guideline objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 A5: Target user group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 B: Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 B1: Literature search and selection of evidence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 Use of existing guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 Systematic literature search . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 Selection of literature identified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 492 B2: Appraisal and extraction of evidence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 493

Adherence influencing factors in patients taking oral anticancer agents: a systematic review.

BACKGROUND The use of oral anticancer agents increased steadily in the last decades. Although oral anticancer agent adherence is important for a successful treatment, many patients are insufficiently adherent. PURPOSE To evaluate adherence influencing factors in patients taking oral anticancer agents. METHODS A systematic literature search was performed in Medline and Embase. Titles and abstracts and in case of relevance, full-texts were screened according to predefined inclusion criteria. The risk of bias was assessed. Both were carried out independently by two reviewers. Relevant data on study characteristics and results were extracted in standardized tables by one reviewer and checked by a second. A meta-analysis was not performed because of clinical and methodological heterogeneity between the studies to avoid misleading results. Data were synthesized in narrative way using a standardized procedure. RESULTS Twenty-two relevant studies were identified. The study quality was moderate. Especially the risk of bias regarding the measurement of influencing factors and adherence was mostly unclear. Social support, intake of aromatase inhibitors, and lower out-of-pocket costs for OACA seem to have a positive effect on adherence. Depression and the number of different medications seem to have a negative effect on adherence. Low age and very high age seem to be associated with lower adherence. The remaining factors showed either mostly no influence or were heterogeneous regarding the effect direction and statistical significance. CONCLUSIONS There are some factors that seem to have influence on adherence in patients taking OACA. However, due to the heterogeneity no general conclusions can be made also for these factors that can be applied to all indications, medications, settings, countries etc. The results should rather be considered as indications for factors that can have an influence on adherence to OACA.

Partial updating of clinical practice guidelines often makes more sense than full updating: a systematic review on methods and the development of an updating procedure.

OBJECTIVES To conduct a systematic review of the methods used to determine when and how to update clinical practice guidelines (CPGs) and develop a procedure for updating CPGs. STUDY DESIGN AND SETTING We searched MEDLINE, Embase, and the Cochrane Methodology Register for methodological publications on updating CPGs. Guideline development manuals were obtained from the Web sites of guideline-developing organizations. Using the information obtained from these records, a procedure for updating CPGs was developed. RESULTS A total of 5,116 journal articles were screened, and seven articles met the criteria for inclusion. Forty-seven manuals were included; of these, eight included details about the methods used to update the guidelines. Most of the included publications focused on assessing whether the CPGs needed updating and not on how to update them. The developed procedure includes a systematic monitoring system and a scheduled process for updating the CPGs, which includes guidance on how to determine the type and scope of an update. CONCLUSION Partial updating often makes more sense than updating the whole CPG because topics and recommendations differ in terms of the need for updating. Guideline developers should implement a systematic updating procedure that includes an ongoing monitoring system that is appropriate for the nature of the guideline topics and the capabilities of the developers.