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Featured researches published by Heike Raatz.


European Journal of Nuclear Medicine and Molecular Imaging | 2012

The impact of 18F-FDG PET on the management of patients with suspected large vessel vasculitis

Martin Fuchs; Matthias Briel; Thomas Daikeler; Ulrich A. Walker; Helmut Rasch; Scott Berg; Quinn Kwan-Tai Ng; Heike Raatz; David Jayne; Ina Kötter; Daniel Engelbert Blockmans; Maria C. Cid; Sergio Prieto-González; Peter Lamprecht; Carlo Salvarani; Zaharenia Karageorgaki; Richard A. Watts; Raashid Luqmani; Jan Müller-Brand; Alan Tyndall; Martin A. Walter

PurposeWe aimed to assess the impact of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on the management of patients with suspected large vessel vasculitis.MethodsAn international expert panel determined diagnoses and clinical management in patients with suspected large vessel vasculitis, with and without the results of 18F-FDG PET, respectively. The accuracy of the clinical diagnosis and the resulting clinical management with and without the 18F-FDG PET results were compared using logistic regression models.ResultsThe analysis included 30 patients referred to a tertiary care centre with large vessel vasculitis and 31 controls. 18F-FDG PET had an overall sensitivity of 73.3% [95% confidence interval (CI) 54.1–87.7%], a specificity of 83.9% (95% CI 66.3–94.5%), a positive predictive value of 81.5% (95% CI 61.9–93.7%) and a negative predictive value of 76.5% (95% CI 58.8–89.3%). The diagnostic accuracy of 18F-FDG PET was higher in patients not receiving immunosuppressive drugs (93.3 vs 64.5%, p = 0.006). Taken in context with other available diagnostic modalities, the addition of 18F-FDG PET increased the clinical diagnostic accuracy from 54.1 to 70.5% (p = 0.04). The addition of 18F-FDG PET increased the number of indicated biopsies from 22 of 61 patients (36.1%) to 25 of 61 patients (41.0%) and changed the treatment recommendation in 8 of 30 patients (26.7%) not receiving immunosuppressive medication and in 7 of 31 patients (22.6%) receiving immunosuppressive medication.Conclusion18F-FDG PET is a sensitive and specific imaging tool for large vessel vasculitis, especially when performed in patients not receiving immunosuppressive drugs. It increases the overall diagnostic accuracy and has an impact on the clinical management in a significant proportion of patients.


JAMA | 2014

Prevalence, Characteristics, and Publication of Discontinued Randomized Trials

Benjamin Kasenda; Erik von Elm; John J. You; Anette Blümle; Yuki Tomonaga; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Joerg J. Meerpohl; Mihaela Stegert; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Dirk Bassler; Jason W. Busse; Ignacio Ferreira-González; Francois Lamontagne; Alain Nordmann; Viktoria Gloy; Heike Raatz; Lorenzo Moja; Rachel Rosenthal; Shanil Ebrahim; Stefan Schandelmaier; Sun Xin; Per Olav Vandvik

IMPORTANCE The discontinuation of randomized clinical trials (RCTs) raises ethical concerns and often wastes scarce research resources. The epidemiology of discontinued RCTs, however, remains unclear. OBJECTIVES To determine the prevalence, characteristics, and publication history of discontinued RCTs and to investigate factors associated with RCT discontinuation due to poor recruitment and with nonpublication. DESIGN AND SETTING Retrospective cohort of RCTs based on archived protocols approved by 6 research ethics committees in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics and planned recruitment from included protocols. Last follow-up of RCTs was April 27, 2013. MAIN OUTCOMES AND MEASURES Completion status, reported reasons for discontinuation, and publication status of RCTs as determined by correspondence with the research ethics committees, literature searches, and investigator surveys. RESULTS After a median follow-up of 11.6 years (range, 8.8-12.6 years), 253 of 1017 included RCTs were discontinued (24.9% [95% CI, 22.3%-27.6%]). Only 96 of 253 discontinuations (37.9% [95% CI, 32.0%-44.3%]) were reported to ethics committees. The most frequent reason for discontinuation was poor recruitment (101/1017; 9.9% [95% CI, 8.2%-12.0%]). In multivariable analysis, industry sponsorship vs investigator sponsorship (8.4% vs 26.5%; odds ratio [OR], 0.25 [95% CI, 0.15-0.43]; P < .001) and a larger planned sample size in increments of 100 (-0.7%; OR, 0.96 [95% CI, 0.92-1.00]; P = .04) were associated with lower rates of discontinuation due to poor recruitment. Discontinued trials were more likely to remain unpublished than completed trials (55.1% vs 33.6%; OR, 3.19 [95% CI, 2.29-4.43]; P < .001). CONCLUSIONS AND RELEVANCE In this sample of trials based on RCT protocols from 6 research ethics committees, discontinuation was common, with poor recruitment being the most frequently reported reason. Greater efforts are needed to ensure the reporting of trial discontinuation to research ethics committees and the publication of results of discontinued trials.


BMJ | 2014

Subgroup analyses in randomised controlled trials: cohort study on trial protocols and journal publications

Benjamin Kasenda; Stefan Schandelmaier; Xin Sun; Erik von Elm; John J. You; Anette Blümle; Yuki Tomonaga; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Joerg J. Meerpohl; Mihaela Stegert; Kelechi K Olu; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Dirk Bassler; Jason W. Busse; Ignacio Ferreira-González; Francois Lamontagne; Alain Nordmann; Viktoria Gloy; Heike Raatz; Lorenzo Moja; Rachel Rosenthal; Shanil Ebrahim

Objective To investigate the planning of subgroup analyses in protocols of randomised controlled trials and the agreement with corresponding full journal publications. Design Cohort of protocols of randomised controlled trial and subsequent full journal publications. Setting Six research ethics committees in Switzerland, Germany, and Canada. Data sources 894 protocols of randomised controlled trial involving patients approved by participating research ethics committees between 2000 and 2003 and 515 subsequent full journal publications. Results Of 894 protocols of randomised controlled trials, 252 (28.2%) included one or more planned subgroup analyses. Of those, 17 (6.7%) provided a clear hypothesis for at least one subgroup analysis, 10 (4.0%) anticipated the direction of a subgroup effect, and 87 (34.5%) planned a statistical test for interaction. Industry sponsored trials more often planned subgroup analyses compared with investigator sponsored trials (195/551 (35.4%) v 57/343 (16.6%), P<0.001). Of 515 identified journal publications, 246 (47.8%) reported at least one subgroup analysis. In 81 (32.9%) of the 246 publications reporting subgroup analyses, authors stated that subgroup analyses were prespecified, but this was not supported by 28 (34.6%) corresponding protocols. In 86 publications, authors claimed a subgroup effect, but only 36 (41.9%) corresponding protocols reported a planned subgroup analysis. Conclusions Subgroup analyses are insufficiently described in the protocols of randomised controlled trials submitted to research ethics committees, and investigators rarely specify the anticipated direction of subgroup effects. More than one third of statements in publications of randomised controlled trials about subgroup prespecification had no documentation in the corresponding protocols. Definitive judgments regarding credibility of claimed subgroup effects are not possible without access to protocols and analysis plans of randomised controlled trials.


Annals of Surgery | 2015

Completion and publication rates of randomized controlled trials in surgery: an empirical study

Rachel Rosenthal; Benjamin Kasenda; Salome Dell-Kuster; Erik von Elm; John J. You; Anette Blümle; Yuki Tomonaga; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Joerg J. Meerpohl; Mihaela Stegert; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Dirk Bassler; Jason W. Busse; Ignacio Ferreira-González; Francois Lamontagne; Alain Nordmann; Viktoria Gloy; Kelechi K Olu; Heike Raatz; Lorenzo Moja; Shanil Ebrahim; Stefan Schandelmaier

OBJECTIVE To investigate the prevalence of discontinuation and nonpublication of surgical versus medical randomized controlled trials (RCTs) and to explore risk factors for discontinuation and nonpublication of surgical RCTs. BACKGROUND Trial discontinuation has significant scientific, ethical, and economic implications. To date, the prevalence of discontinuation of surgical RCTs is unknown. METHODS All RCT protocols approved between 2000 and 2003 by 6 ethics committees in Canada, Germany, and Switzerland were screened. Baseline characteristics were collected and, if published, full reports retrieved. Risk factors for early discontinuation for slow recruitment and nonpublication were explored using multivariable logistic regression analyses. RESULTS In total, 863 RCT protocols involving adult patients were identified, 127 in surgery (15%) and 736 in medicine (85%). Surgical trials were discontinued for any reason more often than medical trials [43% vs 27%, risk difference 16% (95% confidence interval [CI]: 5%-26%); P = 0.001] and more often discontinued for slow recruitment [18% vs 11%, risk difference 8% (95% CI: 0.1%-16%); P = 0.020]. The percentage of trials not published as full journal article was similar in surgical and medical trials (44% vs 40%, risk difference 4% (95% CI: -5% to 14%); P = 0.373). Discontinuation of surgical trials was a strong risk factor for nonpublication (odds ratio = 4.18, 95% CI: 1.45-12.06; P = 0.008). CONCLUSIONS Discontinuation and nonpublication rates were substantial in surgical RCTs and trial discontinuation was strongly associated with nonpublication. These findings need to be taken into account when interpreting surgical literature. Surgical trialists should consider feasibility studies before embarking on full-scale trials.


JAMA Internal Medicine | 2017

Personalized Prescription Feedback Using Routinely Collected Data to Reduce Antibiotic Use in Primary Care: A Randomized Clinical Trial

Lars G. Hemkens; Ramon Saccilotto; Selene Leon Reyes; Dominik Glinz; Thomas Zumbrunn; Oliver Grolimund; Viktoria Gloy; Heike Raatz; Andreas F. Widmer; Andreas Zeller; Heiner C. Bucher

Importance Feedback interventions using routinely collected health data might reduce antibiotic use nationwide without requiring the substantial resources and structural efforts of other antibiotic stewardship programs. Objective To determine if quarterly antibiotic prescription feedback over 2 years reduces antibiotic use when implemented in a complex health care system. Design, Setting, and Participants Pragmatic randomized trial using routinely collected claims data on 2900 primary care physicians with the highest antibiotic prescription rates in Switzerland. Interventions Physicians were randomized to quarterly updated personalized antibiotic prescription feedback over 2 years (n = 1450) or usual care (n = 1450). Feedback was provided both by mail and online from October 2013 to October 2015 and was supported by an initial 1-time provision of evidence-based guidelines. Main Outcomes and Measures The primary outcome was the prescribed defined daily doses (DDD) of any antibiotic to any patient per 100 consultations in the first year analyzed by intention-to-treat. We further analyzed prescriptions of specific antibiotics, age groups, and sex for the first and second year to investigate persistency of effects over time. Results The 2900 physicians had 10 660 124 consultations over 2 years of follow-up, prescribed 1 175 780 packages of antibiotics with 10 290 182 DDD. Physicians receiving feedback prescribed the same amount of antibiotics to all patients in the first year (between-group difference, 0.81%; 95% CI, −2.56% to 4.30%; P = .64) and second year (between-group difference, −1.73%; 95% CI, −5.07% to 1.72%; P = .32) compared with the control group. Prescribing to children aged 6 to 18 years was −8.61% lower in the feedback than in the control group in the first year (95% CI, −14.87% to −1.90%; P = .01). This difference diminished in the second year (between-group difference, −4.10%; 95% CI, −10.78% to 3.07%; P = .25). Physicians receiving feedback prescribed fewer antibiotics to adults aged 19 to 65 years in the second year (between-group difference, −4.59%; 95% CI, −7.91% to −1.16%; P < .01). Prescribing to other patient groups or of specific antibiotic types was not significantly different between groups. Conclusions and Relevance This nationwide antibiotic stewardship program with routine feedback on antibiotic prescribing was not associated with a change of antibiotic use. In older children, adolescents, and younger adults less antibiotics were prescribed, but not consistently over the entire intervention period. Trial Registration clinicaltrials.gov Identifier: NCT01773824


PLOS Medicine | 2016

Agreements between Industry and Academia on Publication Rights: A Retrospective Study of Protocols and Publications of Randomized Clinical Trials

Benjamin Kasenda; Erik von Elm; John J. You; Anette Blümle; Yuki Tomonaga; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Joerg J. Meerpohl; Mihaela Stegert; Kelechi K Olu; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Dirk Bassler; Jason W. Busse; Ignacio Ferreira-González; Francois Lamontagne; Alain Nordmann; Viktoria Gloy; Heike Raatz; Lorenzo Moja; Shanil Ebrahim; Stefan Schandelmaier; Xin Sun; Per Olav Vandvik

Background Little is known about publication agreements between industry and academic investigators in trial protocols and the consistency of these agreements with corresponding statements in publications. We aimed to investigate (i) the existence and types of publication agreements in trial protocols, (ii) the completeness and consistency of the reporting of these agreements in subsequent publications, and (iii) the frequency of co-authorship by industry employees. Methods and Findings We used a retrospective cohort of randomized clinical trials (RCTs) based on archived protocols approved by six research ethics committees between 13 January 2000 and 25 November 2003. Only RCTs with industry involvement were eligible. We investigated the documentation of publication agreements in RCT protocols and statements in corresponding journal publications. Of 647 eligible RCT protocols, 456 (70.5%) mentioned an agreement regarding publication of results. Of these 456, 393 (86.2%) documented an industry partner’s right to disapprove or at least review proposed manuscripts; 39 (8.6%) agreements were without constraints of publication. The remaining 24 (5.3%) protocols referred to separate agreement documents not accessible to us. Of those 432 protocols with an accessible publication agreement, 268 (62.0%) trials were published. Most agreements documented in the protocol were not reported in the subsequent publication (197/268 [73.5%]). Of 71 agreements reported in publications, 52 (73.2%) were concordant with those documented in the protocol. In 14 of 37 (37.8%) publications in which statements suggested unrestricted publication rights, at least one co-author was an industry employee. In 25 protocol-publication pairs, author statements in publications suggested no constraints, but 18 corresponding protocols documented restricting agreements. Conclusions Publication agreements constraining academic authors’ independence are common. Journal articles seldom report on publication agreements, and, if they do, statements can be discrepant with the trial protocol.


Critical Care Medicine | 2016

Premature Discontinuation of Randomized Trials in Critical and Emergency Care: A Retrospective Cohort Study

Stefan Schandelmaier; Erik von Elm; John J. You; Anette Blümle; Yuki Tomonaga; Francois Lamontagne; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Joerg J. Meerpohl; Mihaela Stegert; Kelechi K Olu; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Xin Sun; Dirk Bassler; Jason W. Busse; Ignacio Ferreira-González; Alain Nordmann; Viktoria Gloy; Heike Raatz; Lorenzo Moja; Rachel Rosenthal; Shanil Ebrahim; Per Olav Vandvik

Objectives:Randomized clinical trials that enroll patients in critical or emergency care (acute care) setting are challenging because of narrow time windows for recruitment and the inability of many patients to provide informed consent. To assess the extent that recruitment challenges lead to randomized clinical trial discontinuation, we compared the discontinuation of acute care and nonacute care randomized clinical trials. Design:Retrospective cohort of 894 randomized clinical trials approved by six institutional review boards in Switzerland, Germany, and Canada between 2000 and 2003. Setting:Randomized clinical trials involving patients in an acute or nonacute care setting. Subjects and Interventions:We recorded trial characteristics, self-reported trial discontinuation, and self-reported reasons for discontinuation from protocols, corresponding publications, institutional review board files, and a survey of investigators. Measurements and Main Results:Of 894 randomized clinical trials, 64 (7%) were acute care randomized clinical trials (29 critical care and 35 emergency care). Compared with the 830 nonacute care randomized clinical trials, acute care randomized clinical trials were more frequently discontinued (28 of 64, 44% vs 221 of 830, 27%; p = 0.004). Slow recruitment was the most frequent reason for discontinuation, both in acute care (13 of 64, 20%) and in nonacute care randomized clinical trials (7 of 64, 11%). Logistic regression analyses suggested the acute care setting as an independent risk factor for randomized clinical trial discontinuation specifically as a result of slow recruitment (odds ratio, 4.00; 95% CI, 1.72–9.31) after adjusting for other established risk factors, including nonindustry sponsorship and small sample size. Conclusions:Acute care randomized clinical trials are more vulnerable to premature discontinuation than nonacute care randomized clinical trials and have an approximately four-fold higher risk of discontinuation due to slow recruitment. These results highlight the need for strategies to reliably prevent and resolve slow patient recruitment in randomized clinical trials conducted in the critical and emergency care setting.


Journal of Clinical Epidemiology | 2016

An analysis of protocols and publications suggested that most discontinuations of clinical trials were not based on preplanned interim analyses or stopping rules

Mihaela Stegert; Benjamin Kasenda; Erik von Elm; John J. You; Anette Blümle; Yuki Tomonaga; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Matthias Briel; Joerg J. Meerpohl; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Dirk Bassler; Jason W. Busse; Ignacio Ferreira-González; Francois Lamontagne; Alain Nordmann; Viktoria Gloy; Kelechi K Olu; Heike Raatz; Lorenzo Moja; Rachel Rosenthal; Shanil Ebrahim; Stefan Schandelmaier

OBJECTIVES To investigate the frequency of interim analyses, stopping rules, and data safety and monitoring boards (DSMBs) in protocols of randomized controlled trials (RCTs); to examine these features across different reasons for trial discontinuation; and to identify discrepancies in reporting between protocols and publications. STUDY DESIGN AND SETTING We used data from a cohort of RCT protocols approved between 2000 and 2003 by six research ethics committees in Switzerland, Germany, and Canada. RESULTS Of 894 RCT protocols, 289 prespecified interim analyses (32.3%), 153 stopping rules (17.1%), and 257 DSMBs (28.7%). Overall, 249 of 894 RCTs (27.9%) were prematurely discontinued; mostly due to reasons such as poor recruitment, administrative reasons, or unexpected harm. Forty-six of 249 RCTs (18.4%) were discontinued due to early benefit or futility; of those, 37 (80.4%) were stopped outside a formal interim analysis or stopping rule. Of 515 published RCTs, there were discrepancies between protocols and publications for interim analyses (21.1%), stopping rules (14.4%), and DSMBs (19.6%). CONCLUSION Two-thirds of RCT protocols did not consider interim analyses, stopping rules, or DSMBs. Most RCTs discontinued for early benefit or futility were stopped without a prespecified mechanism. When assessing trial manuscripts, journals should require access to the protocol.


The Journal of Pediatrics | 2017

Premature Discontinuation of Pediatric Randomized Controlled Trials: A Retrospective Cohort Study

Stefan Schandelmaier; Yuki Tomonaga; Dirk Bassler; Joerg J. Meerpohl; Erik von Elm; John J. You; Anette Bluemle; Francois Lamontagne; Ramon Saccilotto; Alain Amstutz; Theresa Bengough; Mihaela Stegert; Kelechi K Olu; Kari A.O. Tikkinen; Ignacio Neumann; Alonso Carrasco-Labra; Markus Faulhaber; Sohail Mulla; Dominik Mertz; Elie A. Akl; Xin Sun; Jason W. Busse; Ignacio Ferreira-González; Alain Nordmann; Viktoria Gloy; Heike Raatz; Lorenzo Moja; Rachel Rosenthal; Shanil Ebrahim; Per Olav Vandvik

Objectives To determine the proportion of pediatric randomized controlled trials (RCTs) that are prematurely discontinued, examine the reasons for discontinuation, and compare the risk for recruitment failure in pediatric and adult RCTs. Study design A retrospective cohort study of RCTs approved by 1 of 6 Research Ethics Committees (RECs) in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics, trial discontinuation, and reasons for discontinuation from protocols, corresponding publications, REC files, and a survey of trialists. Results We included 894 RCTs, of which 86 enrolled children and 808 enrolled adults. Forty percent of the pediatric RCTs and 29% of the adult RCTs were discontinued. Slow recruitment accounted for 56% of pediatric RCT discontinuations and 43% of adult RCT discontinuations. Multivariable logistic regression analyses suggested that pediatric RCT was not an independent risk factor for recruitment failure after adjustment for other potential risk factors (aOR, 1.22; 95% CI, 0.57‐2.63). Independent risk factors were acute care setting (aOR, 4.00; 95% CI, 1.72‐9.31), nonindustry sponsorship (aOR, 4.45; 95% CI, 2.59‐7.65), and smaller planned sample size (aOR, 1.05; 95% CI 1.01‐1.09, in decrements of 100 participants). Conclusion Forty percent of pediatric RCTs were discontinued prematurely, owing predominately to slow recruitment. Enrollment of children was not an independent risk factor for recruitment failure.


Swiss Medical Weekly | 2016

Cost-effectiveness of primarily surgical versus primarily conservative treatment of acute and subacute radiculopathies due to intervertebral disc herniation from the Swiss perspective

Zanfina Ademi; Viktoria Gloy; Dominik Glinz; Heike Raatz; Joris van Stiphout; Heiner C. Bucher; Matthias Schwenkglenks

AIMS OF THE STUDY To assess the cost-effectiveness of primarily surgical treatment (PST) versus primarily conservative treatment (PCT) in adults with intermediate severity, acute or subacute, lumbar radicular syndrome due to intervertebral disc herniation. METHODS A decision analytic model from healthcare system and societal perspectives was used to compare outcomes and costs of PST with those of PCT (physiotherapy, epidural injection and medication). Treatment pathways and quality of life were obtained from published clinical trials. Costs were derived from Swiss health insurance claims data. Swiss clinical experts provided information on use of medication and physiotherapy. The main outcome of interest was incremental cost per quality-adjusted-life-year (QALY) gained over a period of 2 years. Costs and QALYs gained were discounted from the second year, at a rate of 2% per year. RESULTS In the base-case analysis from a healthcare system perspective, over 2 years, PST compared with PCT led to 0.0634 additional QALYs per person, at an additional net cost of CHF 7198 per person. The corresponding incremental cost effectiveness ratio (ICER) amounted to CHF 113 396 per QALY gained. From a societal perspective the ICER was CHF 70 711 per QALY gained. ICERs were subject to substantial uncertainty because of limitations in available data. CONCLUSION A PST approach, when compared with PCT, may be cost effective from a societal perspective based on a willingness-to-pay threshold of CHF 100 000 per QALY gained. However, it is less likely to be cost effective from the perspective of the Swiss healthcare system. More research is needed to understand the long-term economic implications among this patient group.

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Viktoria Gloy

University Hospital of Basel

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Elie A. Akl

American University of Beirut

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Alain Amstutz

University Hospital of Basel

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Mihaela Stegert

University Hospital of Basel

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