Bio

Clinical Focus


  • Internal Medicine

Academic Appointments


Administrative Appointments


  • Instructor, Stanford University (2012 - Present)
  • Postdoctoral Research Fellow, Stanford Prevention Research Center & Palo Alto Medical Foundation Research Institute (2010 - 2012)
  • Clinical Instructor, Stanford University (2006 - 2010)
  • Research Associate, UCSF, JAMA (1994 - 1998)

Honors & Awards


  • Award for Excellence in Teaching of Medical Students, Stanford University (2008)
  • Dean's Summer and Quarterly Research Fellowships, UCSF (1999-2002)
  • Tucker Scholarship, UCSF (2002)
  • Taussig Scholarship, UCSF (2001)
  • Phi Beta Kappa Graduate Research Scholarship, Phi Beta Kappa Society (2000)

Professional Education


  • Medical Education:Univ of California San Francisco (2003) CA
  • Residency:University of Washington (2006) WA
  • Board Certification: Internal Medicine, American Board of Internal Medicine (2006)
  • Internship:University of Washington (2004) WA
  • M.D., UCSF (2003)
  • B.A., Harvard College (1994)

Community and International Work


  • Parent Advisory Board, HeadsUp Daycare (2006-2009), Palo Alto

    Location

    Bay Area

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

Research & Scholarship

Clinical Trials


  • Doctors and Web-based Self-management Support Pilot Study Not Recruiting

    Doctors and web-based self-management support pilot study will test whether health professionals' observation of an online patient workshop on self-management of diabetes and participation in structured learning sessions on self-management strategies will change the attitudes and confidence of physicians and other health professionals regarding their willingness and ability to perform self-management interventions with patients. If this pilot suggests that attitudes and confidence levels can change, we hope to launch a larger study to examine this method of learning and its effectiveness in more detail.

    Stanford is currently not accepting patients for this trial. For more information, please contact Diana Laurent, (650) 723 - 7935.

    View full details

Publications

Journal Articles


  • Short-term weight loss patterns, baseline predictors, and longer-term follow-up within a randomized controlled trial OBESITY Yank, V., Xiao, L., Wilson, S. R., Stafford, R. S., Rosas, L. G., Ma, J. 2014; 22 (1): 45-51

    Abstract

    OBJECTIVE: To examine weight loss patterns and predictors among participants in a primary care-based translation study of the Diabetes Prevention Program lifestyle intervention. DESIGN AND METHODS: Cluster analysis identified short-term (12-week) weight loss patterns among 72 intervention participants. Analysis of variance assessed cluster differences in weight loss maintenance at 15-month follow-up. Discriminant analysis identified baseline characteristics that best differentiated between clusters. RESULTS: Participants had baseline mean (SD) age of 55.0 (10.8) years and BMI of 31.9 (5.2) kg/m(2) . Cluster analysis identified three short-term weight loss patterns: modest (n=15; 21%), moderate-and-steady (n=43; 60%), and substantial-and-early (n=14; 19%). Only participants with the latter two patterns achieved clinically significant (≥ 5%) short-term weight loss and maintained it at 15 months. On discriminant analysis, the modest cluster was most differentiated from other clusters by high friend encouragement for dietary change, high obesity-related problems, and low physical well-being. The moderate-and-steady cluster was differentiated by lower physical activity, family encouragement, and depression symptoms. CONCLUSION: Results provide insight into the heterogeneity of response to an effective lifestyle intervention by identifying short-term weight loss patterns and their baseline predictors and relationship to 15-month success. If replicated, results may help tailor strategies for participant subgroups in weight loss programs.

    View details for DOI 10.1002/oby.20510

    View details for Web of Science ID 000329613600011

    View details for PubMedID 23740619

  • The Effects of a Long-Term Physical Activity Intervention on Serum Uric Acid in Older Adults at Risk for Physical Disability JOURNAL OF AGING AND PHYSICAL ACTIVITY Beavers, K. M., Hsu, F., Serra, M. C., Yank, V., Pahor, M., Nicklas, B. J. 2014; 22 (1): 25-33

    Abstract

    Observational studies show a relationship between elevated serum uric acid (UA) and better physical performance and muscle function. The purpose of this paper was to determine whether regular participation in an exercise intervention, known to improve physical functioning, would result in increased serum UA. 424 elderly men and women at risk for physical disability were randomized to participate in either a 12-month moderate-intensity physical activity (PA) or health education (SA) intervention. UA was measured at baseline, 6- and 12-months (n= 368, 341 and 332, respectively). Baseline UA levels were 6.03±1.52 mg/dL and 5.94±1.55 mg/dL in the PA and SA groups, respectively. The adjusted mean UA at month 12 was 4.8% (0.24 mg/dL) higher in the PA compared to the SA group (p=0.028). Compared to a health education intervention, a one-year PA intervention results in a modest increase in systemic concentration of UA in elderly individuals at risk for mobility disability.

    View details for DOI 10.1123/JAPA:2012-0018

    View details for Web of Science ID 000329896100003

    View details for PubMedID 23295313

  • Variations Between Obese Latinos and Whites in Weight-Related Counseling During Preventive Clinical Visits in the United States OBESITY Ma, J., Xiao, L., Yank, V. 2013; 21 (8): 1734-1741

    Abstract

    OBJECTIVE: To examine rate differences and explanatory factors for lifestyle counseling to obese Latinos versus non-Hispanic whites (NHWs) in U.S. outpatient settings. DESIGN AND METHODS: The 2009 National Ambulatory Medical Care Survey data assessed the provision of weight-related lifestyle counseling during general medical exam visits (n = 688) by obese Latino and NHW adults. The Blinder-Oaxaca decomposition technique to identify the fraction of the overall ethnic difference in counseling rate explained by a selection of measured variables based on the Anderson-Newman-Aday behavioral model were used. RESULTS: Although weight-related lifestyle counseling rates were low in both ethnic groups, the rate among obese Latinos (51.3%) was significantly higher than among NHWs (35.8%) (P = 0.03), with 60% of the difference explained by observed factors. Enabling factors such as provider specialty, metropolitan statistical area, practice type, and provider employment type contributed the most to higher counseling rates among Latinos, whereas geographic region, continuity of care, and health insurance were enabling factors that, along with the predisposing factor of sex, contributed the most in the opposite direction. CONCLUSIONS: Obese Latinos are more likely to receive weight-related counseling during general medical exams than do NHWs, which is partly explained by physician practice and patient factors.

    View details for DOI 10.1002/oby.20285

    View details for Web of Science ID 000323521500034

    View details for PubMedID 23696497

  • An Easily Accessible Web-Based Minimization Random Allocation System for Clinical Trials JOURNAL OF MEDICAL INTERNET RESEARCH Xiao, L., Huang, Q., Yank, V., Ma, J. 2013; 15 (7): 279-288

    Abstract

    Minimization as an adaptive allocation technique has been recommended in the literature for use in randomized clinical trials. However, it remains uncommonly used due in part to a lack of easily accessible implementation tools.To provide clinical trialists with a robust, flexible, and readily accessible tool for implementing covariate-adaptive biased-coin randomization.We developed a Web-based random allocation system, MinimRan, that applies Pocock-Simon (for trials with 2 or more arms) and 2-way (currently limited to 2-arm trials) minimization methods for trials using only categorical prognostic factors or the symmetric Kullback-Leibler divergence minimization method for trials (currently limited to 2-arm trials) using continuous prognostic factors with or without categorical factors, in covariate-adaptive biased-coin randomization.In this paper, we describe the system's essential statistical and computer programming features and provide as an example the randomization results generated by it in a recently completed trial. The system can be used in single- and double-blind trials as well as single-center and multicenter trials.We expect the system to facilitate the translation of the 3 validated random allocation methods into broad, efficient clinical research practice.

    View details for DOI 10.2196/jmir.2392

    View details for Web of Science ID 000324620300021

    View details for PubMedID 23872035

  • Translating an evidence-based lifestyle intervention program into primary care: lessons learned. Health promotion practice Blonstein, A. C., Yank, V., Stafford, R. S., Wilson, S. R., Rosas, L. G., Ma, J. 2013; 14 (4): 491-497

    Abstract

    The E-LITE (Evaluation of Lifestyle Interventions to Treat Elevated Cardiometabolic Risk in Primary Care) trial evaluated the feasibility and potential effectiveness of translating an evidence-based lifestyle intervention for the management of obesity and related risk factors in a primary care setting. Delivered by allied health care providers, the intervention promoted at least 7% weight loss and at least 150 minutes per week of moderate-intensity physical activity through gradual, sustainable lifestyle changes. Activities included interactive group lessons, food tasting, guided physical activity, and technology-mediated self-monitoring and behavioral counseling. This article discusses insights and potential areas for improvement to strengthen program implementation for dissemination of the E-LITE program to other primary care settings. We focus on (a) the role of allied health professionals in program delivery, (b) strengthening program integration within a primary care clinic, and (c) the use of information technology to extend the reach and impact of the program. Our experience shows the feasibility of implementing an evidence-based lifestyle intervention program combining group-delivered nutrition and behavioral counseling, physical activity training, and technology-mediated follow-up in a primary care setting. Challenges remain, and we offer possible solutions to overcome them.

    View details for DOI 10.1177/1524839913481604

    View details for PubMedID 23539264

  • Translating the Diabetes Prevention Program Lifestyle Intervention for Weight Loss Into Primary Care A Randomized Trial JAMA INTERNAL MEDICINE Ma, J., Yank, V., Xiao, L., Lavori, P. W., Wilson, S. R., Rosas, L. G., Stafford, R. S. 2013; 173 (2): 113-121

    Abstract

    The Diabetes Prevention Program (DPP) lifestyle intervention reduced the incidence of type 2 diabetes mellitus (DM) among high-risk adults by 58%, with weight loss as the dominant predictor. However, it has not been adequately translated into primary care.We evaluated 2 adapted DPP lifestyle interventions among overweight or obese adults who were recruited from 1 primary care clinic and had pre-DM and/or metabolic syndrome. Participants were randomized to (1) a coach-led group intervention (n = 79), (2) a self-directed DVD intervention (n = 81), or (3) usual care (n = 81). During a 3-month intensive intervention phase, the DPP-based behavioral weight-loss curriculum was delivered by lifestyle coach-led small groups or home-based DVD. During the maintenance phase, participants in both interventions received lifestyle change coaching and support remotely-through secure email within an electronic health record system and the American Heart Association Heart360 website for weight and physical activity goal setting and self-monitoring. The primary outcome was change in body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) from baseline to 15 months.At baseline, participants had a mean (SD) age of 52.9 (10.6) years and a mean BMI of 32.0 (5.4); 47% were female; 78%, non-Hispanic white; and 17%, Asian/Pacific Islander. At month 15, the mean ± SE change in BMI from baseline was -2.2 ± 0.3 in the coach-led group vs -0.9 ± 0.3 in the usual care group (P < .001) and -1.6 ± 0.3 in the self-directed group vs usual care (P = .02). The percentages of participants who achieved the 7% DPP-based weight-loss goal were 37.0% (P = .003) and 35.9% (P = .004) in the coach-led and self-directed groups, respectively, vs 14.4% in the usual care group. Both interventions also achieved greater net improvements in waist circumference and fasting plasma glucose level.Proven effective in a primary care setting, the 2 DPP-based lifestyle interventions are readily scalable and exportable with potential for substantial clinical and public health impact.clinicaltrials.gov Identifier: NCT00842426.

    View details for DOI 10.1001/2013.jamainternmed.987

    View details for Web of Science ID 000317239700008

    View details for PubMedID 23229846

  • Two-year weight-loss maintenance in primary care-based Diabetes Prevention Program lifestyle interventions. Nutrition & diabetes Xiao, L., Yank, V., Wilson, S. R., Lavori, P. W., Ma, J. 2013; 3

    Abstract

    Objective:To investigate whether the effects on weight loss and cardiometabolic risk factor reduction of two technology-mediated lifestyle interventions for 15 months in a primary care-based translation trial sustained at 24 months (that is, 9 months after the end of intervention).Design:This study analyzed data from an extended follow-up of participants in the original 'E-LITE' (Evaluation of Lifestyle Interventions to Treat Elevated Cardiometabolic Risk in Primary Care)-randomized controlled trial, which demonstrated the effectiveness of two adapted Diabetes Prevention Program (DPP) lifestyle interventions compared with usual primary care.Subjects:E-LITE randomized 241 overweight or obese participants with pre-diabetes and/or metabolic syndrome to receive usual care alone (n=81) or usual care plus a coach-led (n=79) or self-directed intervention (n=81). The interventions provided coach-led group behavioral weight-loss treatment or a take-home, self-directed DVD using the same 12-week curriculum, followed by 12 additional months of technology-mediated coach contact and self-monitoring support. Participants received no further intervention after month 15. A blinded assessor conducted 24-month visits by following the measurement protocols of the original trial. Measurements include weight and cardiometabolic risk factors (waist circumference, fasting plasma glucose, resting blood pressure, triglycerides, high- and low-density lipoprotein cholesterol, total cholesterol and triglyceride to high-density lipoprotein cholesterol ratio).Results:At month 24, mean±s.e. changes in body mass index (trial primary outcome) and weight (kg) from baseline were -1.9±0.3 (P=0.001) and -5.4±0.9 (P<0.001) in the coach-led intervention, and -1.6±0.3 (P=0.03) and -4.5±0.9 (P=0.001) in the self-directed intervention, compared with -0.9±0.3 and 2.4±0.9 in the usual care group. In addition, both interventions led to a greater percentage of participants maintaining ?7% weight loss and sustained improvements in waist circumference and fasting plasma glucose levels than usual care.Conclusion:This study shows sustained benefits of the two primary care-based, technology-mediated DPP lifestyle interventions. The findings warrant replication in long-term studies involving diverse populations.

    View details for DOI 10.1038/nutd.2013.17

    View details for PubMedID 23797383

  • Baseline reach and adoption characteristics in a randomized controlled trial of two weight loss interventions translated into primary care: A structured report of real-world applicability CONTEMPORARY CLINICAL TRIALS Yank, V., Stafford, R. S., Rosas, L. G., Ma, J. 2013; 34 (1): 126-135

    Abstract

    Although the Diabetes Prevention Program (DPP) lifestyle intervention reduced type 2 diabetes incidence by 58% among high-risk adults at academic centers, it requires translation into typical primary care settings. Using baseline data from the Evaluation of Lifestyle Interventions to Treat Elevated Cardiometabolic Risk in Primary Care (E-LITE) randomized controlled trial, we evaluated the potential of its two DPP-based interventions to reach their target populations and be adopted into routine use.Overweight/obese adults with increased cardiometabolic risk enrolled from one primary care clinic. Using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) model, we assessed reach with data on patient identification, participation, and representativeness, and adoption with data on intervention feasibility and potential for organizational diffusion.The target population was identified by searching electronic health records. Contact was attempted for 2391 patients who completed initial screening by phone (56% uptake) or online (44%). Most (88%) of those screened ineligible were not within the target population; 12% were excluded because of research requirements. Conservatively estimated participation rate was 44%. Participants (n=241) included 54% men and had a mean (SD) age of 52.9 years (10.6) and body mass index of 32 kg/m(2) (5.4). Regarding adoption, all clinic physicians agreed to participate. The feasibility of intervention implementation and dissemination was enhanced by leveraging existing intervention, training, and primary care resources.E-LITE's lifestyle interventions had fair-to-good potential for primary care reach and adoption. Our trial evidence and structured reporting may inform real-world implementation of translational trials by health networks, physicians, and payers.

    View details for DOI 10.1016/j.cct.2012.10.007

    View details for Web of Science ID 000314448300016

    View details for PubMedID 23124047

  • Web-based self-management support training for health professionals: A pilot study PATIENT EDUCATION AND COUNSELING Yank, V., Laurent, D., Plant, K., Lorig, K. 2013; 90 (1): 29-37

    Abstract

    To evaluate a web-based self-management training for health professionals. Patients spend 99% of their time outside the healthcare system. Thus self-management support from health professionals is central to optimal care. Our objective was to teach health professionals the skills to provide this support.Primary care residents and practicing providers enrolled in six groups. Each group received four web-based interactive training sessions derived from self-efficacy theory. Retrospective-pre/post assessed changes in self-management beliefs and confidence. Wilcoxon signed-rank tests with Bonferroni correction compared responses. Focus groups solicited qualitative feedback.Fifty-seven residents and providers across the United States enrolled. Residents demonstrated positive changes on all belief questions (P 0.001-0.012). Practicing providers had a non-significant positive change on one and significant changes on the remainder (P 0.001-0.018). Both types of participants demonstrated significant increases on confidence questions regarding their ability to support self-management (P<0.01 for all). Participants described learned techniques as being useful, reducing burnout, and increasing acceptance of patient involvement in care planning.The web-based self-management support training for health professionals was feasible and changed beliefs and confidence.The program may maximize patient self-management by increasing provider self-efficacy and skill for self-management support.

    View details for DOI 10.1016/j.pec.2012.09.003

    View details for Web of Science ID 000314012100006

    View details for PubMedID 23031610

  • Algorithm for balancing both continuous and categorical covariates in randomized controlled trials COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE Xiao, L., Yank, V., Ma, J. 2012; 108 (3): 1185-1190

    Abstract

    Minimization as proposed by Pocock and Simon for balancing categorical covariates in clinical trials with individual-level, consecutive randomization has been increasingly used. An extension of the method exists that uses the symmetric Kullback-Leibler divergence index to balance both categorical and continuous covariates, albeit for two-arm randomized controlled trials only. To date, the algorithm has not been made widely available to researchers via publicly accessible software. We adapted Endo et al.'s algorithm to randomized trials with two or more arms. In addition, our algorithm incorporates Efron's biased coin method to decrease the predictability of assignment even when a predefined threshold of difference in the numbers of subjects between treatment arms is reached, whereas Endo et al.'s algorithm assigns the next subject to the treatment of smaller size with certainty. We developed code in the free statistical software R to make the algorithm readily available to trialists. While there are no definitive answers regarding the optimal choices for certain statistical parameters that must be defined prior to algorithm application (P(k), D(n), and p_D(n)), we provide guidance on these. We conducted simulations with actual data from a three-arm randomized trial to compare the modified algorithm and R code to another published biased coin minimization method that can accommodate continuous and categorical covariates in multi-arm trials. The three-arm trial used three categorical covariates (sex, race/ethnicity, and online personal health record access) and four continuous covariates (age, fasting blood glucose, body mass index, and waist circumference). All of the continuous and categorical covariates were well balanced, and the results were comparable to the comparison method.

    View details for DOI 10.1016/j.cmpb.2012.06.001

    View details for Web of Science ID 000311976100027

    View details for PubMedID 22727633

  • Randomized Trial of Personal Genomics for Preventive Cardiology Design and Challenges CIRCULATION-CARDIOVASCULAR GENETICS Knowles, J. W., Assimes, T. L., Kiernan, M., Pavlovic, A., Goldstein, B. A., Yank, V., McConnell, M. V., Absher, D., Bustamante, C., Ashley, E. A., Ioannidis, J. P. 2012; 5 (3): 368-376
  • Baseline reach and adoption characteristics in a randomized controlled trial of two weight loss interventions translated into primary care: a structured report of real-world applicability Contemp Clin Trials 2012 (accepted for publication). Yank V, Stafford RS, Rosas LG, Ma J 2012
  • Off-Label Use of Recombinant Factor VIIa in US Hospitals: Analysis of Hospital Records ANNALS OF INTERNAL MEDICINE Logan, A. C., Yank, V., Stafford, R. S. 2011; 154 (8): 516-W175

    Abstract

    Recombinant factor VIIa (rFVIIa) is approved for treatment of bleeding in patients who have hemophilia with inhibitors but has been applied to a wide range of off-label indications.To estimate patterns of off-label rFVIIa use in U.S. hospitals.Retrospective database analysis.Data were extracted from the Premier Perspectives database (Premier, Charlotte, North Carolina), which contains discharge records from a sample of academic and nonacademic U.S. hospitals. Patients: 12 644 hospitalizations for patients who received rFVIIa during a hospital stay.Hospital diagnoses and patient dispositions from 1 January 2000 to 31 December 2008. Statistical weights for each hospital were used to provide national estimates of rFVIIa use.From 2000 to 2008, off-label use of rFVIIa in hospitals increased more than 140-fold, such that in 2008, 97% (95% CI, 96% to 98%) of 18 311 in-hospital uses were off-label. In contrast, in-hospital use for hemophilia increased less than 4-fold and accounted for 2.7% (CI, 1.9% to 3.5%) of use in 2008. Adult and pediatric cardiovascular surgery (29% [CI, 21% to 33%]), body and brain trauma (29% [CI, 19% to 38%]), and intracranial hemorrhage (11% [CI, 7.7% to 14%]) were the most common indications for rFVIIa use. Across all indications, in-hospital mortality was 27% (CI, 19% to 34%) and 43% (CI, 26% to 59%) of patients were discharged to home.Accuracy and completeness of the discharge diagnoses and patient medication records in the database sample cannot be verified.Off-label use of rFVIIa in the hospital setting far exceeds use for approved indications. These patterns raise concern about the application of rFVIIa to conditions for which strong supporting evidence is lacking.

    View details for Web of Science ID 000289622000014

    View details for PubMedID 21502649

  • Systematic Review: Benefits and Harms of In-Hospital Use of Recombinant Factor VIIa for Off-Label Indications ANNALS OF INTERNAL MEDICINE Yank, V., Tuohy, C. V., Logan, A. C., Bravata, D. M., Staudenmayer, K., Eisenhut, R., Sundaram, V., McMahon, D., Olkin, I., McDonald, K. M., Owens, D. K., Stafford, R. S. 2011; 154 (8): 529-W190

    Abstract

    Recombinant factor VIIa (rFVIIa), a hemostatic agent approved for hemophilia, is increasingly used for off-label indications.To evaluate the benefits and harms of rFVIIa use for 5 off-label, in-hospital indications: intracranial hemorrhage, cardiac surgery, trauma, liver transplantation, and prostatectomy.Ten databases (including PubMed, EMBASE, and the Cochrane Library) queried from inception through December 2010. Articles published in English were analyzed.Two reviewers independently screened titles and abstracts to identify clinical use of rFVIIa for the selected indications and identified all randomized, controlled trials (RCTs) and observational studies for full-text review.Two reviewers independently assessed study characteristics and rated study quality and indication-wide strength of evidence.16 RCTs, 26 comparative observational studies, and 22 noncomparative observational studies met inclusion criteria. Identified comparators were limited to placebo (RCTs) or usual care (observational studies). For intracranial hemorrhage, mortality was not improved with rFVIIa use across a range of doses. Arterial thromboembolism was increased with medium-dose rFVIIa use (risk difference [RD], 0.03 [95% CI, 0.01 to 0.06]) and high-dose rFVIIa use (RD, 0.06 [CI, 0.01 to 0.11]). For adult cardiac surgery, there was no mortality difference, but there was an increased risk for thromboembolism (RD, 0.05 [CI, 0.01 to 0.10]) with rFVIIa. For body trauma, there were no differences in mortality or thromboembolism, but there was a reduced risk for the acute respiratory distress syndrome (RD, -0.05 [CI, -0.02 to -0.08]). Mortality was higher in observational studies than in RCTs.The amount and strength of evidence were low for most outcomes and indications. Publication bias could not be excluded.Limited available evidence for 5 off-label indications suggests no mortality reduction with rFVIIa use. For some indications, it increases thromboembolism.

    View details for Web of Science ID 000289622000016

    View details for PubMedID 21502651

  • Safety of Recombinant Activated Factor VII in Randomized Clinical Trials NEW ENGLAND JOURNAL OF MEDICINE Yank, V., Stafford, R. S. 2011; 364 (6): 575-575

    View details for Web of Science ID 000287139900018

    View details for PubMedID 21306248

  • Comparative Effectiveness of Recombinant Factor VIIa for Off-Label Indications vs. Usual Care. Comparative Effectiveness Review No. 21. (Prepared by Stanford-UCSF Evidence-based Practice Center under Contract No. #290-02-0017) Rockville, MD: Agency for Healthcare Research and Quality. May 2010. Available at: www.effectivehealthcare.ahrq.gov/reports/final.cfm. Yank V, Tuohy CV, Logan AC, Bravata DM, Staudenmayer K, Eisenhut R, Sundaram V, McMahon D, Stave CD, Zehnder JL, Olkin I, McDonald KM, Owens DK, Stafford RS 2010
  • Financial ties and concordance between results and conclusions in meta-analyses: retrospective cohort study BRITISH MEDICAL JOURNAL Yank, V., Rennie, D., Bero, L. A. 2007; 335 (7631): 1202-?

    Abstract

    To determine whether financial ties to one drug company are associated with favourable results or conclusions in meta-analyses on antihypertensive drugs.Retrospective cohort study.Meta-analyses published up to December 2004 that were not duplicates and evaluated the effects of antihypertensive drugs compared with any comparator on clinical end points in adults. Financial ties were categorised as one drug company compared with all others.The main outcomes were the results and conclusions of meta-analyses, with both outcomes separately categorised as being favourable or not favourable towards the study drug. We also collected data on characteristics of meta-analyses that the literature suggested might be associated with favourable results or conclusions.124 meta-analyses were included in the study, 49 (40%) of which had financial ties to one drug company. On univariate logistic regression analyses, meta-analyses of better methodological quality were more likely to have favourable results (odds ratio 1.16, 95% confidence interval 1.07 to 1.27). Although financial ties to one drug company were not associated with favourable results, such ties constituted the only characteristic significantly associated with favourable conclusions (4.09, 1.30 to 12.83). When controlling for other characteristics of meta-analyses in multiple logistic regression analyses, meta-analyses that had financial ties to one drug company remained more likely to report favourable conclusions (5.11, 1.54 to 16.92).Meta-analyses on antihypertensive drugs and with financial ties to one drug company are not associated with favourable results but are associated with favourable conclusions.

    View details for DOI 10.1136/bmj.39376.447211.BE

    View details for Web of Science ID 000251707800035

    View details for PubMedID 18024482

  • Bronchial-pulmonary artery fistula with fatal massive Hemoptysis caused by anastomotic bronchial aspergillus infection in a lung transplant recipient RESPIRATORY CARE Slatore, C. G., Yank, V., Jewell, K. D., Fligner, C. L. 2007; 52 (11): 1542-1545

    View details for Web of Science ID 000250788200014

    View details for PubMedID 17971258

  • Consensus and contention regarding redundant publications in clinical research: cross-sectional survey of editors and authors JOURNAL OF MEDICAL ETHICS Yank, V., Barnes, D. 2003; 29 (2): 109-114

    Abstract

    To examine the perspectives of journal editors and authors on overlapping and redundant publications in clinical research.Pretested cross-sectional survey, containing both forced choice and open ended questions, administered by mail to the senior editors (N=99) and one randomly selected author (N=99) from all journals in the Abridged Index Medicus (1996) that published clinical research.The views of editors and authors about the extent of redundant publications, why they occur, how to prevent and respond to cases, and when the publication of overlapping manuscripts is justified.Seventy two per cent (N=71) of editors and 65% (N=64) of authors completed the survey. There was consensus between both groups that redundant publications occur because authors feel the pressure to publish and journals do not do enough to publicise, criticise, and punish cases, and that the publication of most types of overlapping articles is unacceptable. Sixty seven per cent of authors but only 31% of editors felt, however, that it was justified to publish an overlapping article in a non-peer reviewed symposium supplement, and 68% of editors but 39% of authors supported imposing restrictions on guilty authors' future submissions. In written comments, 15% to 30% of both groups emphasised that it was justified to publish overlapping articles when there were different or non-English-speaking audiences, new data, strengthened methods, or disputed findings.Editors, authors, and other academic leaders should together develop explicit guidelines that clarify points of contention and ambiguity regarding overlapping manuscripts.

    View details for Web of Science ID 000182155800014

    View details for PubMedID 12672892

  • Reporting of informed consent and ethics committee approval in clinical trials JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Yank, V., Rennie, D. 2002; 287 (21): 2835-2838

    Abstract

    To determine whether journals have improved their disclosure of ethical protections in clinical trials.Comparison of clinical trials published before and after 1997 (July 1995 to December 1996 and January 1998 to June 1999) in Annals of Internal Medicine, BMJ, JAMA, The Lancet, and The New England Journal of Medicine. Sixty articles per journal per period were randomly selected and assessed for rate of reporting on informed consent and on ethics committee approval.Informed consent was not described in 79 articles (26%) published before 1997 vs 53 (18%) published after 1997 (P =.01), and ethics committee approval was not mentioned in 93 (31%) before 1997 vs 54 (18%) after 1997 (P<.001). Neither protection was described in 48 articles (16%) published before 1997 vs 28 (9%) after 1997 (P =.01). In subgroup analyses, those journals with the worst initial rates generally improved the most. BMJ did not describe informed consent in 25 articles (42%) before 1997 vs 15 (25%) after 1997 (P =.05), and JAMA did not describe ethics committee approval in 25 (42%) before 1997 vs 13 (22%) after 1997 (P =.02). BMJ, JAMA, and Annals had the lowest initial rates of reporting on both protections in the same article, with 25 (42%), 32 (53%), and 34 (57%), respectively, but improved markedly to 38 (63%), 43 (72%), and 45 (75%) (P =.02,.04, and.03, respectively).Major medical journals have improved their reporting on informed consent and ethics committee approval; however, 9% of studies still report neither.

    View details for Web of Science ID 000176002200024

    View details for PubMedID 12038927

  • Prevalence of honorary and ghost authorship in Cochrane reviews JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Mowatt, G., Shirran, L., Grimshaw, J. J., Rennie, D., Flanagin, A., Yank, V., MacLennan, G., Gotzsche, P. C., Bero, L. A. 2002; 287 (21): 2769-2771

    Abstract

    To determine the prevalence of honorary and ghost authorship in Cochrane reviews, how authorship is assigned, and the ways in which authors and Cochrane editorial teams contribute.Using a Web-based, self-administered survey, corresponding authors for 577 reviews published in issues 1 and 2 from 1999 of The Cochrane Library were invited to report on the prevalence of honorary and ghost authors, contributions by authors listed in the byline and members of Cochrane editorial teams, and identification of methods of assigning authorship. Responses were received for 362 reviews (63% response rate), which contained 913 authors.One hundred forty-one reviews (39%) had evidence of honorary authors, 32 (9%) had evidence of ghost authors (most commonly a member of the Cochrane editorial team), and 9 (2%) had evidence of both honorary and ghost authors. The editorial teams contributed in a wide variety of ways to 301 reviews (83%). Authorship was decided by the group of authors (31%) or lead author (25%) in most reviews. Authorship order was assigned according to contribution in most reviews (76%). The 3 functions contributed to most by those listed in the byline were assessing the quality of included studies (83%), interpreting data (82%), and abstracting data from included studies (77%).A substantial proportion of reviews had evidence of honorary and ghost authorship. The Cochrane editorial teams contributed to most Cochrane reviews.

    View details for Web of Science ID 000176002200004

    View details for PubMedID 12038907

  • The Criticism Management System for The Cochrane Library EVALUATION & THE HEALTH PROFESSIONS Ober, M., Shohara, R., Rennie, D., Yank, V., Bero, L. A. 2002; 25 (1): 98-115

    Abstract

    In April 1997, the Cochrane Collaboration implemented the Criticism Management System for The Cochrane Library, allowing readers to electronically submit criticisms on Cochrane reviews and protocols. As a result of resource constraints and user feedback, the Criticism Management System evolved through three different versions. Major problems have included difficult access to the system, a lack of automation within the system, a low number of submissions (171 criticisms submitted per 1,388 reviews), and a low response rate to these criticisms by authors of reviews (26 criticisms have received published responses). These low figures suggest that users of The Cochrane Library are not commenting on the published reviews or not using the Criticism Management System to make their criticisms known to the authors. An easier-to-use system and better ways of encouraging feedback from readers and responses from reviewers are needed in the future.

    View details for Web of Science ID 000187396300007

    View details for PubMedID 11868449

  • The contributions of authors JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Rennie, D., Flanagin, A., Yank, V. 2000; 284 (1): 89-91

    View details for Web of Science ID 000087843000032

    View details for PubMedID 10872020

  • Disclosure of researcher contributions: A study of original research articles in The Lancet ANNALS OF INTERNAL MEDICINE Yank, V., Rennie, D. 1999; 130 (8): 661-670

    Abstract

    Authorship disputes and abuses have increased in recent years. In response to a proposal that researcher contributions be specified for readers, The Lancet began disclosing such contributions at the end of original articles.To analyze the descriptions researchers use for their contributions and to determine how the order of names on the byline corresponds to these contributions, whether persons listed on the byline fulfill a lenient version of the criteria for authorship specified by the International Committee of Medical Journal Editors (the Vancouver Group), and whether the contributions of persons listed as contributors overlap with the contributions of those who are acknowledged.Descriptive study.A taxonomy of researchers' contributions was developed and applied to researchers' self-reported contributions to original research articles published in The Lancet from July to December 1997.Contributors lists occupied little page space (mean, 2.5 cm of column length). Placement on the byline did not indicate the specific category of task performed, although the first-contributor position corresponded to a significantly greater number of contributions (mean numbers of contributions: first-contributor position, 3.23; second-contributor position, 2.51; third-contributor position, 2.20; and fourth-contributor position, 2.51) (P < 0.01). Forty-four percent of contributors on the byline did not fulfill a lenient version of the Vancouver Group's criteria for authorship. Sixty percent of the most common categories of activities described on contributors lists overlapped with those on acknowledgements lists.Publication of lists that specify contributions to research articles is feasible and seems to impart important information. The criteria for authorship outlined by the Vancouver Group do not seem to be congruent with the self-identified contributions of researchers.

    View details for Web of Science ID 000079786600006

    View details for PubMedID 10215563

  • If authors became contributors, everyone would gain, especially the reader AMERICAN JOURNAL OF PUBLIC HEALTH Rennie, D., Yank, V. 1998; 88 (5): 828-830

    View details for Web of Science ID 000074114000037

    View details for PubMedID 9585760

  • When authorship fails - A proposal to make contributors accountable JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Rennie, D., Yank, V., Emanuel, L. 1997; 278 (7): 579-585

    Abstract

    A published article is the primary means whereby new work is communicated, priority is established, and academic promotion is determined. Publication depends on trust and requires that authors be held to standards of honesty, completeness, and fairness in their reporting, and to accountability for their statements. The system of authorship, while appropriate for articles with only 1 author, has become inappropriate as the average number of authors of an article has increased; as the work of coauthors has become more specialized and relationships between them have become more complex; and as both credit and, even more, responsibility have become obscured and diluted. Credit and accountability cannot be assessed unless the contributions of those named as authors are disclosed to readers, so the system is flawed. We argue for a radical conceptual and systematic change, to reflect the realities of multiple authorship and to buttress accountability. We propose dropping the outmoded notion of author in favor of the more useful and realistic one of contributor. This requires disclosure to readers of the contributions made to the research and to the manuscript by the contributors, so that they can accept both credit and responsibility. In addition, certain named contributors take on the role of guarantor for the integrity of the entire work. The requirement that all participants be named as contributors will eliminate the artificial distinction between authors and acknowledgees and will enhance the integrity of publication.

    View details for Web of Science ID A1997XQ98600033

    View details for PubMedID 9268280

  • Disclosure to the reader of institutional review board approval and informed consent JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Rennie, D., Yank, V. 1997; 277 (11): 922-923

    View details for Web of Science ID A1997WM77400038

    View details for PubMedID 9062333

Conference Proceedings


  • Comparison of Thromboembolic Event Rates in Randomized Controlled Trials and Observational Studies of Recombinant Factor VIIa for Off-Label Indications. Yank, V., Logan, A. C., Tuohy, C. V., Bravata, D. M., Staudenmayer, K., Eisenhut, R., Sundaram, V., McMahon, D., McDonald, K. M., Owens, D., Stafford, R. S. AMER SOC HEMATOLOGY. 2009: 571-572

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