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AHRQ Research Studies
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Research Studies is a compilation of published research articles funded by AHRQ or authored by AHRQ researchers.
Results
26 to 50 of 52 Research Studies DisplayedNi Y, Bermudez M, Kennebeck S
A real-time automated patient screening system for clinical trials eligibility in an emergency department: design and evaluation.
This study assessed the effectiveness of using a natural language processing system called Automated Clinical Trial Eligibility Screener (ACTES) compared to traditional screening methods to recruit patients in the emergency department for a clinical trial. ACTES was fully integrated into the pediatric emergency department at Cincinnati Children’s Hospital Medical center for a 12-month period. A 34% time saving rate was found overall and that saved time was redirected to other activities such as study-related administrative tasks and work-related conversations.
AHRQ-funded; HS024983.
Citation: Ni Y, Bermudez M, Kennebeck S .
A real-time automated patient screening system for clinical trials eligibility in an emergency department: design and evaluation.
JMIR Med Inform 2019 Jul 24;7(3):e14185. doi: 10.2196/14185..
Keywords: Emergency Department, Research Methodologies
Yoon G, Jiang W, Liu L
Simple quasi-bayes approach for modeling mean medical costs.
AHRQ-funded; HS020263.
Citation: Yoon G, Jiang W, Liu L .
Simple quasi-bayes approach for modeling mean medical costs.
Int J Biostat 2019 Jun 5;16(1). doi: 10.1515/ijb-2018-0122..
Keywords: Healthcare Costs, Research Methodologies
Masho SW, Ihongbe TO, Wan W
Effectiveness of shortened time interval to postpartum visit in improving postpartum attendance: design and rationale for a randomized controlled trial.
Recent evidence suggests that there are numerous benefits to scheduling postpartum visits as early as 3 weeks post-delivery. However, findings are not conclusive due to methodological limitations. This report discussed the unique aspects of a randomized controlled trial's (RCT) design, intervention, and strategies to maintain participant retention. The study design offered unique features which ensured excellent participant completion and adherence rates, despite the presence of hard-to-track women who typically do not return for their postpartum visits.
AHRQ-funded; HS021504.
Citation: Masho SW, Ihongbe TO, Wan W .
Effectiveness of shortened time interval to postpartum visit in improving postpartum attendance: design and rationale for a randomized controlled trial.
Contemp Clin Trials 2019 Jun;81:40-43. doi: 10.1016/j.cct.2019.04.012..
Keywords: Maternal Care, Pregnancy, Women, Patient Adherence/Compliance, Research Methodologies
Desai RJ, Wyss R, Abdia Y
Evaluating the use of bootstrapping in cohort studies conducted with 1:1 propensity score matching - a plasmode simulation study.
Bootstrapping can account for uncertainty in propensity score (PS) estimation and matching processes in 1:1 PS-matched cohort studies. While theory suggests that the classical bootstrap can fail to produce proper coverage, practical impact of this theoretical limitation in settings typical to pharmacoepidemiology is not well studied. In a plasmode-based simulation study, the investigators compared performance of the standard parametric approach, which ignores uncertainty in PS estimation and matching, with two bootstrapping methods.
AHRQ-funded; HS022193.
Citation: Desai RJ, Wyss R, Abdia Y .
Evaluating the use of bootstrapping in cohort studies conducted with 1:1 propensity score matching - a plasmode simulation study.
Pharmacoepidemiol Drug Saf 2019 Jun;28(6):879-86. doi: 10.1002/pds.4784..
Keywords: Research Methodologies, Patient-Centered Outcomes Research, Medication
Ren Y, Lin L, Lian Q
Real-world performance of meta-analysis methods for double-zero-event studies with dichotomous outcomes using the Cochrane Database of Systematic Reviews.
Meta-analysis combines multiple independent studies, which can increase power and provide better estimates. However, it is unclear how best to deal with studies with zero events; such studies are also known as double-zero-event studies (DZS). This study provided a real-world performance of meta-analysis methods for double-zero-event studies with dichotomous outcomes using the Cochrane Database of Systematic Reviews. The investigators concluded that to utilize all available information and reduce research waste and avoid overestimating the effect, meta-analysts should incorporate DZS, rather than simply removing them.
AHRQ-funded; HS024743.
Citation: Ren Y, Lin L, Lian Q .
Real-world performance of meta-analysis methods for double-zero-event studies with dichotomous outcomes using the Cochrane Database of Systematic Reviews.
J Gen Intern Med 2019 Jun;34(6):960-68. doi: 10.1007/s11606-019-04925-8..
Keywords: Research Methodologies
Ji X, Shen HW, Ritter A
Visual exploration of neural document embedding in information retrieval: semantics and feature selection.
Researchers proposed visual exploration of neural document embedding to gain insights into the underlying embedding space and to promote the utilization in prevalent information retrieval applications. They demonstrated the usefulness and effectiveness of their application-driven view and presented inspiring findings in use cases. They indicated that their work will help designers/developers of downstream applications gain insights and confidence in neural document embedding.
AHRQ-funded; HS025047.
Citation: Ji X, Shen HW, Ritter A .
Visual exploration of neural document embedding in information retrieval: semantics and feature selection.
IEEE Trans Vis Comput Graph 2019 Jun;25(6):2181-92. doi: 10.1109/tvcg.2019.2903946..
Keywords: Health Services Research (HSR), Research Methodologies
Istl AC, Ruck JM, Morris CD
Call for improved design and reporting in soft tissue sarcoma studies: a systematic review and meta-analysis of chemotherapy and survival outcomes in resectable STS.
Researchers completed a meta-analysis of chemotherapy in localized STS, assessing OS, PFS, and local and distant recurrence. They found no benefit of chemotherapy over locoregional therapy alone for all-comers or site-specific STS. Recommendations to improve outcome reporting and quality indices are suggested.
AHRQ-funded; HS024736.
Citation: Istl AC, Ruck JM, Morris CD .
Call for improved design and reporting in soft tissue sarcoma studies: a systematic review and meta-analysis of chemotherapy and survival outcomes in resectable STS.
J Surg Oncol 2019 Jun;119(7):824-35. doi: 10.1002/jso.25401..
Keywords: Cancer, Treatments, Evidence-Based Practice, Mortality, Outcomes, Research Methodologies
Anselin L, Li X
Operational local join count statistics for cluster detection.
The author of this article paper describes a statistical approach that provides an alternative to point-pattern-based statistics in situations where all the potential locations of an event are available. This approach uses a local indicator of spatial association (LISA) for situations where the variables of interest are binary, which yields a conditional version of a local join count statistic. The statistic is extended to a bivariate and multivariate context, including an explicit treatment of co-location. Examples are provided which investigate local clusters of house sales in Detroit and urban design characteristics of Chicago 2017 census blocks.
AHRQ-funded; HS021752.
Citation: Anselin L, Li X .
Operational local join count statistics for cluster detection.
J Geogr Syst 2019 Jun;21(2):189-210. doi: 10.1007/s10109-019-00299-x..
Keywords: Research Methodologies
Richardson DB, Keil AP, Kinlaw AC
Marginal structural models for risk or prevalence ratios for a point exposure using a disease risk score.
The disease risk score is a summary score that can be used to control for confounding with a potentially large set of covariates. Focusing on the simple case of a binary point exposure, the investigators describe a marginal structural model for estimation of risk (or prevalence) ratios. Simulations were used to illustrate the approach, and an empirical example was provided.
AHRQ-funded; HS000032.
Citation: Richardson DB, Keil AP, Kinlaw AC .
Marginal structural models for risk or prevalence ratios for a point exposure using a disease risk score.
Am J Epidemiol 2019 May;188(5):960-66. doi: 10.1093/aje/kwz025..
Keywords: Research Methodologies
Millar MM, Kinney AY, Camp NJ
Predictors of response outcomes for research recruitment through a central cancer registry: evidence from 17 recruitment efforts for population-based studies.
The authors conducted multivariable mixed-effects logistic regression to identify case and study characteristics associated with making contact with and obtaining cooperation of Utah cancer cases. They found that characteristics associated with lower odds of contact included Hispanic ethnicity, nonwhite race, and younger age at contact. Years since diagnosis was inversely associated with making contact. Increased odds of cooperation were associated with including a questionnaire, postage stamps, and incentives. They concluded that obtaining high response is challenging, but study features identified in this analysis support better results when recruiting through central cancer registries.
AHRQ-funded; HS019356; HS022640.
Citation: Millar MM, Kinney AY, Camp NJ .
Predictors of response outcomes for research recruitment through a central cancer registry: evidence from 17 recruitment efforts for population-based studies.
Am J Epidemiol 2019 May;188(5):928-39. doi: 10.1093/aje/kwz011..
Keywords: Cancer, Patient-Centered Outcomes Research, Evidence-Based Practice, Registries, Outcomes, Research Methodologies
Wisk LE, Nelson EB, Magane KM
Clinical trial recruitment and retention of college students with type 1 diabetes via social media: an implementation case study.
The purpose of this study was to quantify the efficiency and acceptability of Internet-based recruitment for engaging college-students with type 1 diabetes (T1D) and to describe the approach used for implementing a health-related trial entirely online using off-the-shelf Internet tools. Young people aged 17-25 years with T1D were recruited through social media platforms and other outreach channels; Facebook was the highest yield recruitment source. Demographics differed by platform. Response rate and participant characteristics were quantified and engagement metrics tracked via Google Analytics and participant survey data. The researchers conclude that recruitment of college students with T1D for a trial via social media is feasible, efficient, acceptable, and yields a sample that represents the user-base from which they were drawn.
AHRQ-funded; HS022986.
Citation: Wisk LE, Nelson EB, Magane KM .
Clinical trial recruitment and retention of college students with type 1 diabetes via social media: an implementation case study.
J Diabetes Sci Technol 2019 May;13(3):445-56. doi: 10.1177/1932296819839503..
Keywords: Diabetes, Health Services Research (HSR), Research Methodologies, Social Media, Young Adults
Wheatley LM, Wood R, Nadeau K
Mind the gaps: clinical trial concepts to address unanswered questions in aeroallergen immunotherapy-an NIAID/AHRQ workshop.
A joint AHRQ and National Institute of Allergy and Infectious Diseases (NIAAD) workshop was held to develop trial concepts that could improve the use and effectiveness of aeroallergen immunotherapy (AAIT). Four different expert groups were formed to propose different study designs. These study designs would create clinical trials of long duration and would need highly characterized patient populations.
AHRQ-funded; 290200710061I.
Citation: Wheatley LM, Wood R, Nadeau K .
Mind the gaps: clinical trial concepts to address unanswered questions in aeroallergen immunotherapy-an NIAID/AHRQ workshop.
J Allergy Clin Immunol 2019 May;143(5):1711-26. doi: 10.1016/j.jaci.2019.01.032..
Keywords: Asthma, Comparative Effectiveness, Evidence-Based Practice, Prevention, Research Methodologies, Respiratory Conditions
Marshall IJ, Marshall R, Wallace BC
Rapid reviews may produce different results to systematic reviews: a meta-epidemiological study.
Researchers analyzed the difference in results between systematic reviews and rapid reviews. They stimulated searching only PubMed, excluding older articles, smaller trials, and using the largest trial only. They examined percentage changes in pooled odds ratios (ORs), statistical significance, and biases between systematic reviews and rapid reviews. A total of 2,512 systematic reviews were included. Using only PubMed had the smallest risk of changed ORs. There were also changes in statistical significance but no evidence of bias. They concluded that rapid reviews can be considered where approximately 10% risk of the primary outcome or by changing greater than 20% could be tolerated.
AHRQ-funded; HS025024.
Citation: Marshall IJ, Marshall R, Wallace BC .
Rapid reviews may produce different results to systematic reviews: a meta-epidemiological study.
J Clin Epidemiol 2019 May;109:30-41. doi: 10.1016/j.jclinepi.2018.12.015..
Keywords: Evidence-Based Practice, Health Services Research (HSR), Research Methodologies
Dunn AG, Orenstein L, Coiera E
The timing and frequency of trial inclusion in systematic reviews of type 2 diabetes drugs was associated with trial characteristics.
The purpose of this study was to determine whether certain trial characteristics are associated with faster or more frequent inclusion in systematic reviews for drug interventions in type 2 diabetes. Results showed that time to inclusion was shorter for trials with industry funding, more participants, and published in higher impact factor journals, while frequency of inclusion was greater for trials with industry funding, more participants, positive conclusions, and published in higher impact factor journals.
AHRQ-funded; HS024798.
Citation: Dunn AG, Orenstein L, Coiera E .
The timing and frequency of trial inclusion in systematic reviews of type 2 diabetes drugs was associated with trial characteristics.
J Clin Epidemiol 2019 May;109:62-69. doi: 10.1016/j.jclinepi.2019.01.009..
Keywords: Diabetes, Medication, Research Methodologies
Goodman KE, Lessler J, Harris AD
A methodological comparison of risk scores versus decision trees for predicting drug-resistant infections: a case study using extended-spectrum beta-lactamase (ESBL) bacteremia.
Timely identification of multidrug-resistant gram-negative infections remains an epidemiological challenge. Statistical models for predicting drug resistance can offer utility where rapid diagnostics are unavailable or resource-impractical. The investigators previously reported on a decision tree for predicting extended-spectrum beta-lactamase bloodstream (ESBL) infections. Their objective in the current study was to develop a risk score from the same ESBL dataset to compare these 2 methods and to offer general guiding principles for using each approach.
AHRQ-funded; HS025089.
Citation: Goodman KE, Lessler J, Harris AD .
A methodological comparison of risk scores versus decision trees for predicting drug-resistant infections: a case study using extended-spectrum beta-lactamase (ESBL) bacteremia.
Infect Control Hosp Epidemiol 2019 Apr;40(4):400-07. doi: 10.1017/ice.2019.17..
Keywords: Research Methodologies, Risk, Infectious Diseases
Natafgi N, Tafari AT, Chauhan C
Patients' early engagement in research proposal development (PEER-PD): patients guiding the proposal writing.
Patient engagement often starts after research funding is secured with little or no involvement of patients in the proposal development phase. This paper compared three levels of patient engagement and described patients' early engagement in the research proposal development process and its contemporary relevance to clinical and translational research. The paper also addressed key patient considerations and questions that had an impact on the proposal development.
AHRQ-funded; HS022135.
Citation: Natafgi N, Tafari AT, Chauhan C .
Patients' early engagement in research proposal development (PEER-PD): patients guiding the proposal writing.
J Comp Eff Res 2019 Apr;8(6):441-53. doi: 10.2217/cer-2018-0129..
Keywords: Research Methodologies, Patient-Centered Outcomes Research, Comparative Effectiveness, Evidence-Based Practice
Li X, Fireman BH, Curtis JR
Validity of privacy-protecting analytical methods that use only aggregate-level information to conduct multivariable-adjusted analysis in distributed data networks.
Researchers analyzed the impact of using distributed data networks to conduct large-scale epidemiologic studies on protecting privacy of the subjects. Three aggregate-level data-sharing approaches were tested (risk-set, summary-table, and effect-estimate). Four confounding adjustment methods (matching, stratification, inverse probability matching, and matching weighting) and 2 summary scores (propensity and disease risk) for binary and time-to-event-outcomes were assessed. Risk-set data sharing generally performed better than summary-table and effect-estimate data-sharing which often produced discrepancies in settings with rare outcomes and small sample sizes.
AHRQ-funded; HS026214.
Citation: Li X, Fireman BH, Curtis JR .
Validity of privacy-protecting analytical methods that use only aggregate-level information to conduct multivariable-adjusted analysis in distributed data networks.
Am J Epidemiol 2019 Apr;188(4):709-23. doi: 10.1093/aje/kwy265..
Keywords: Data, Research Methodologies
Han B, Yu H
Causal difference-in-differences estimation for evaluating the impact of semi-continuous medical home scores on health care for children.
For the purposes of this paper, "medical homeness" is a semi-continuous score ranging from 0 to 100 to indicate the extent to which a patient-centered medical home model is achieved. The researchers developed a causal difference-in-differences approach to estimating the effects of a treatment with semi-continuous dosages. They found that there was a roughly linear effect of medical homeness scores on the annual number of visits to doctor offices when medical homeness scores were below 60 points. The number of office visits did not further increase when medical homeness scores were above 60. A similar relationship was found between medical homeness scores and ratings for health care quality.
AHRQ-funded; HS023336.
Citation: Han B, Yu H .
Causal difference-in-differences estimation for evaluating the impact of semi-continuous medical home scores on health care for children.
Health Serv Outcomes Res Methodol 2019 Mar;19(1):61-78. doi: 10.1007/s10742-018-00195-9..
Keywords: Patient-Centered Healthcare, Children/Adolescents, Research Methodologies
Adrian M, Moreno M, Nicodimos S
Research strategy for health sciences: Facebook friend request is non-differentially accepted in a diverse, young adult population.
The aim of this study was to report on overall success of recruiting young adults in diverse settings, with respect to education and employment, into a study using Facebook (FB). The investigators assert that friending through FB is a feasible way to reach young adults involved in health and behavioral research, and could be a way to expand the populations that are studied in health science research to maximize generalizability of the conclusions drawn.
AHRQ-funded; HS022982.
Citation: Adrian M, Moreno M, Nicodimos S .
Research strategy for health sciences: Facebook friend request is non-differentially accepted in a diverse, young adult population.
Nurs Health Sci 2019 Mar;21(1):71-77. doi: 10.1111/nhs.12557..
Keywords: Health Services Research (HSR), Research Methodologies, Social Media, Young Adults
Cherla DV, Viso CP, Holihan JL
The effect of financial conflict of interest, disclosure status, and relevance on medical research from the United States.
The aim of this study was to determine if authors who fail to disclose reportable conflicts of interest (COI) are more likely to publish findings that are favorable to industry than authors with no COI. The investigators found that all financial COIs (disclosed or undisclosed, relevant or not relevant, research or non-research) influence whether studies report findings favorable to industry sponsors.
AHRQ-funded; HS023009.
Citation: Cherla DV, Viso CP, Holihan JL .
The effect of financial conflict of interest, disclosure status, and relevance on medical research from the United States.
J Gen Intern Med 2019 Mar;34(3):429-34. doi: 10.1007/s11606-018-4784-0..
Keywords: Evidence-Based Practice, Research Methodologies
Desai K, Carroll I, Asch S
Extremely large outlier treatment effects may be a footprint of bias in trials from less developed countries: randomized trials of gabapentinoids.
This meta-analyses looked at extremely large outlier treatment effects for clinical trials of gabapentinoids conducted in less developed countries. Researchers identified 10 meta-analyses that showed statistically significant favorable findings. In four meta-analyses, heterogeneity estimates exceeded 90% for postoperative pain. Those 4 meta-analyses showed 39 out of 77 studies with extremely favorable results and out of those 39, 33 were conducted in less developed countries with no tradition of favorable research, 22 reported no information on funding, and 20 reported no conflicts of interest. Conversely, 27 of 38 studies with unfavorable results came from developed countries.
AHRQ-funded; HS024096.
Citation: Desai K, Carroll I, Asch S .
Extremely large outlier treatment effects may be a footprint of bias in trials from less developed countries: randomized trials of gabapentinoids.
J Clin Epidemiol 2019 Feb;106:80-87. doi: 10.1016/j.jclinepi.2018.10.012..
Keywords: Medication, Research Methodologies
Gartlehner G, Nussbaumer-Streit B, Wagner G
Increased risks for random errors are common in outcomes graded as high certainty of evidence.
The goal of this article was to assess the risk for random errors in outcomes graded as high certainty of evidence (CoE). Results showed that, overall, 38% of high CoE outcomes had increased risks for random errors. Outcomes assessing harms were more frequently affected than outcomes assessing benefits. Regrading of outcomes with increased random errors showed that 74% should have been downgraded based on current guidance. Recommendations included being aware that outcomes rated as high CoE often have increased risks for false-positive or false-negative findings.
AHRQ-funded; HS024749.
Citation: Gartlehner G, Nussbaumer-Streit B, Wagner G .
Increased risks for random errors are common in outcomes graded as high certainty of evidence.
J Clin Epidemiol 2019 Feb;106:50-59. doi: 10.1016/j.jclinepi.2018.10.009..
Keywords: Evidence-Based Practice, Health Services Research (HSR), Patient-Centered Outcomes Research, Research Methodologies
Hunter SR, Applegate EA, Arora V
An introduction to multiobjective simulation optimization.
The authors provide an introduction to multiobjective simulation optimization at the advanced tutorial level, aimed at researchers and practitioners who wish to begin working in this area. Their introduction includes an overview of existing theory, methods, and provably convergent algorithms. Key open questions that remain in this emerging field are also discussed.
AHRQ-funded; HS024384.
Citation: Hunter SR, Applegate EA, Arora V .
An introduction to multiobjective simulation optimization.
ACM Trans. Model. Comput. Simul. 2019 Feb;29(1):1-36. doi: 10.1145/3299872..
Keywords: Health Services Research (HSR), Research Methodologies
Lin L, Xing A, Kofler MJ
Borrowing of strength from indirect evidence in 40 network meta-analyses.
This study investigated the use of network meta-analysis (NMA) in providing clinicians with direct and indirect evidence when comparing multiple treatment options. Researchers analyzed 915 possible treatment combinations although 53% had no direct evidence. They concluded that the potential to provide more precise results only reliably occurs when at least two head-to-head studies are available and the treatments are well connected.
AHRQ-funded; HS024743.
Citation: Lin L, Xing A, Kofler MJ .
Borrowing of strength from indirect evidence in 40 network meta-analyses.
J Clin Epidemiol 2019 Feb;106:41-49. doi: 10.1016/j.jclinepi.2018.10.007..
Keywords: Evidence-Based Practice, Health Services Research (HSR), Research Methodologies
Riley AR, Freeman KA
Impacting pediatric primary care: opportunities and challenges for behavioral research in a shifting healthcare landscape.
This commentary discusses the role that behavioral analysts can have in partnership with pediatric medicine. There have been advances, but there has been limited impact for the daily practice of pediatrics. The authors discuss why behavioral pediatrics has failed to gain traction in primary care, describe possible opportunities for an expanded portfolio of research, and identify several examplars from the behavior analytic literature that has influenced pediatric primary care, and make further recommendations for producing influential data.
AHRQ-funded; HS022981.
Citation: Riley AR, Freeman KA .
Impacting pediatric primary care: opportunities and challenges for behavioral research in a shifting healthcare landscape.
Behav Anal 2019 Feb;19(1):23-38. doi: 10.1037/bar0000114..
Keywords: Behavioral Health, Children/Adolescents, Health Services Research (HSR), Healthcare Delivery, Patient-Centered Healthcare, Patient-Centered Outcomes Research, Primary Care, Primary Care: Models of Care, Research Methodologies