Aggregator: a machine learning approach to identifying MEDLINE articles that derive from the same underlying clinical trial

Objective It is important to identify separate publications that report outcomes from the same underlying clinical trial, in order to avoid over-counting these as independent pieces of evidence. Methods We created positive and negative training sets (comprised of pairs of articles reporting on the same condition and intervention) that were, or were not, linked to the same clinicaltrials.gov trial registry number. Features were extracted from MEDLINE and PubMed metadata; pairwise similarity scores were modeled using logistic regression. Results Article pairs from the same trial were identified with high accuracy (F1 score = 0.843). We also created a clustering tool, Aggregator, that takes as input a PubMed user query for RCTs on a given topic, and returns article clusters predicted to arise from the same clinical trial. Discussion Although painstaking examination of full-text may be needed to be conclusive, metadata are surprisingly accurate in predicting when two articles derive from the same underlying clinical trial

A study of the value of requesting information from drug manufacturers for systematic reviews; 9 years of experience from the drug effectiveness review project

Abstract Background Systematic reviews (SRs) depend on comprehensive searches for evidence to provide balanced, accurate results. Requesting published and unpublished studies from pharmaceutical manufacturers has been proposed as a method to engage industry stakeholders and potentially reduce reporting bias. The Drug Effectiveness Review Project (DERP) has been requesting such evidence since 2003; the purpose of this study was to retrospectively evaluate the type and impact of the evidence received. Methods Data from “dossiers” submitted by pharmaceutical manufacturers for a set of 40 SRs conducted for DERP from July 2006 to June 2015 were retrospectively evaluated. Characteristics of data submitted in dossiers, including numbers, types, and characteristics of studies submitted and then included in DERP SRs, were abstracted. Time trends, study quality, publication status, and whether the submission represented a unique study or supplemental data to a published study were assessed. The impact of this evidence on SR conclusions was assessed using dual review. Differences were resolved through a consensus. Results Over 9 years, 160 dossiers were received, relating to 40 DERP SRs. Out of 7360 studies/datasets submitted, 2.2% (160) were included in a SR. The ratio of submitted-to-included increased over time. Most were unique studies (23% were supplemental data sets), and almost 42% of the studies were unpublished. The majority of the studies were rated fair quality, with 7.3% rated good and 14% rated poor quality by the original SR authors. Considering all literature search sources, 7.2% of all studies included in the 40 SRs came from a dossier, and 16% of dossier studies were included in a meta-analysis. The dossier studies resulted in changes to conclusions in 42% of the SRs. Out of 46 unpublished unique studies included in a SR, 25 (54%) influenced the conclusions in favor of the manufacturers drug, 8% favored a competitor drug, and 40% favored neither. In 92% of cases favoring the manufacturer’s drug, the dossier study was the only evidence for that drug in a specific population or outcome. Conclusions In SRs conducted for DERP, few studies submitted by pharmaceutical manufacturers were ultimately included in a SR. The included data helped to reduce reporting and publication bias by filling important gaps and in some cases led to altered conclusions

Military Factors Associated with Smoking in Veterans

Introduction: Given the high prevalence of smoking among Veterans and the economic, social, and clinical implications, it is important to understand the factors that contribute to smoking in order to focus efforts to mitigate these factors and improve smoking cessation efforts among Veterans. The availability of research on smoking in Veterans compared with civilians is limited given the military-specific differences in their life course. We aimed to identify military-specific factors combined with sociodemographic factors for ever smoking and current smoking among Veterans to inform future interventions. Materials and Methods: We used data from the 2010 National Survey of Veterans, the most current, to analyze the association of sociodemographic and military-specific factors with ever versus never smoking, and current versus past smoking using multiple variable logistic regression models (IRB#4125). Results: Among 8,618 respondents, the proportions of current, past, and never smokers were 17%, 48%, and 34%, respectively. Sociodemographic factors associated with ever smoking were female gender, educational attainment of less than a bachelor’s degree, and being divorced/separated/widowed. Military-specific factors associated with ever smoking were exposure to dead/dying/wounded soldiers during service, and past, current, and unsure enrollment in Veterans Affairs healthcare. Never smoking was associated with Hispanic ethnicity, income over $75,000, and reporting fair or poor health. Military factors associated with never smoking were presence of a service-connected disability and military service July 1964 or earlier (i.e., pre-Vietnam). Among 5,652 ever smokers, sociodemographic factors associated with current smoking were age less than 65, being non-Hispanic black, educational attainment of less than a bachelor’s degree, being divorced/separated/widowed, never married, and having no insurance. Factors associated with reduced likelihood of current smoking compared with past smoking included income \u3e$41,000 and reporting fair or poor health. Military-specific variables associated with reduced likelihood of current smoking were service era of May 1975 or later (i.e., post-Vietnam) and 5 or more years of service. Conclusion: Military-specific variables are associated with smoking behaviors among Veterans. Findings from this study that exposure to dead/dying/wounded soldiers, service era, duration of service, service-connected disability status, and enrollment in VA care all influence smoking in Veterans, can inform prevention and cessation efforts in part by encouraging alternative healthy habits or cessation techniques in subgroups of Veterans with particular military backgrounds. By assessing risk factors in this unique population future research can leverage these findings to determine mechanisms that help explain these associations. Identifying factors associated with smoking offers insights for smoking cessation and prevention interventions given the military experiences and increased smoking incidence among Veterans

Lung cancer specialists' opinions on treatment for stage I non-small cell lung cancer: A multidisciplinary survey

Purpose: The current standard of care for surgically eligible stage I non-small cell lung cancer (NSCLC) is surgical resection, but emerging data suggest that stereotactic body radiation therapy (SBRT) is potentially as effective as surgery. However, specialist views of the current evidence about SBRT and how they would incorporate a randomized controlled trial (RCT) into practice is unclear. We sought to understand specialist opinions about evidence regarding treatment of stage I NSCLC and how this translates into practice and clinical trial implementation. Methods and materials: We used a 28-item, web-based survey that invited all participating providers from the American Society for Radiation Oncology, American Thoracic Society Thoracic Oncology Assembly, and the International Association for the Study of Lung Cancer to share opinions regarding practice beliefs, treatment of stage I NSCLC, and a clinical trial scenario. Results: A total of 959 surveys were completed; 64% were from radiation oncologists (ROs) and 49% were from outside the United States. The majority of ROs (80%) reported that current evidence indicates that SBRT has the same or a better benefit compared with surgery for surgically eligible patients with stage I NSCLC; 28% of non–radiation oncologists (NROs) indicated the same (P < .01). Almost all ROs (94%), compared with 62% of NROs, would permit surgically eligible patients to enroll in an RCT of SBRT versus surgery (P < .01). Most ROs (82%) and NROs (87%) believed that changing practice in thoracic surgery would be somewhat difficult, very difficult, or impossible (P = .066) even if an RCT showed better survival with SBRT. Conclusions: NROs believe that SBRT is much less effective than surgery, contrary to ROs, who believe that they are similar. Most would support an RCT, but NROs would do so less. Changes in surgical practice may be challenging even if an RCT shows better mortality and quality of life with SBRT. These results are helpful in the creation and dissemination of RCTs that are designed to understand this question