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Rasmussen, Luke V.

https://orcid.org/0000-0002-4497-8049

Mayo Clinic

Northwestern University

Citations 20

Using a translational data platform to create clinical-grade genome-informed risk assessments
Morse, Jennifer L, He, Megan, Bangash, Hana , Cortopassi, Joshua, Forman, Sophie, Gordon, Adam S, Hamed, Marwan, Karlson, Elizabeth W. , Kiryluk, K, Kullo, Iftikhar J, Lewis, Adam, Limdi, Nita, Marathe, Priya, McGuffin, Kyle, Odgis, Jacqueline, Perez, Emma, Petrzelka, Jacob, Prows, Cynthia A. , Thomas, Ellis, Wiesner, Georgia L. , Wilson, Travis, Linder, Jodell E. , Liu, Cong , Rasmussen, Luke V , Morse, Jennifer L. , Chung, Wendy K. , Cortopassi, Josh , Gordon, Adam S, Harris, Paul A. , Kenny, Eimear E , Kiryluk, Krzysztof , Kullo, Iftikhar J. , Lewis, Adam J. , Liu, Cong , Marathe, Priya , McGuffin, Kyle, Odgis, Jacqueline A. , Perez, Emma , Rasmussen, Luke V. , Thomas, Ellis, Peterson, Josh F.

JAMIA Open | July 13, 2026 | Volume: 9 | Issue: 4 | Pages: No page available

10.1093/jamiaopen/ooag118 Get It

Abstract Objective To describe the development and implementation of an automated platform for genomic risk prediction that integrates multiple data types. Materials and methods Using the REDCap infrastructure, we constructed the R4 (Recruitment, Results, and Risk Reduction) platform to intake data from clinical sites, partner laboratories, participant surveys, and electronic health record (EHR) data across 13 institutions. Results The R4 Portal successfully integrated data to generate genome-informed risk assessments (GIRAs) across 11 conditions for a 23 840 person cohort. Testing phases and quality control led to network-wide protocols ensuring consistency and accuracy. Discussion As the science of estimating disease risk evolves, standardized and high-throughput methods of collecting and manipulating complex data are required. Platforms should be open-source, modular, and reusable, ensuring flexibility, security, and integration across healthcare environments. Conclusion The electronic MEdical Records and GEnomics (eMERGE) network successfully generated and returned comprehensive risk profiles using logic and data specific to 11 conditions in a secure and semi-automated fashion employing a customized REDCap database.
PhenoFit: a framework for determining computable phenotyping algorithm fitness for purpose and reuse
Wiley, Laura K. , Rasmussen, Luke V. , Levinson, Rebecca T. , Malinowski, Jennifer , Manemann, Sheila M., Wilson, Melissa P. , Chapman, Martin , Pacheco, Jennifer A. , Walunas, Theresa L. , Starren, Justin , Richesson, Rachel , Malinowski, Jennnifer , Starren, Justin B , Bielinski, Suzette , Richesson, Rachel L , Rasmussen, Luke V , Pacheco, Jennifer A , Wiley, Laura K , Walunas, Theresa L , Bielinski, Suzette J.

Journal of the American Medical Informatics Association | November 12, 2025 | Volume: 33 | Issue: 2 | Pages: 536-542

10.1093/jamia/ocaf195 Get It

Abstract Background Computational phenotyping from electronic health records (EHRs) is essential for clinical research, decision support, and quality/population health assessment, but the proliferation of algorithms for the same conditions makes it difficult to identify which algorithm is most appropriate for reuse. Objective To develop a framework for assessing phenotyping algorithm fitness for purpose and reuse. Fitness for Purpose Phenotyping algorithms are fit for purpose when they identify the intended population with performance characteristics appropriate for the intended application. Fitness for Reuse Phenotyping algorithms are fit for reuse when the algorithm is implementable and generalizable—that is, it identifies the same intended population with similar performance characteristics when applied to a new setting. Conclusions The PhenoFit framework provides a structured approach to evaluate and adapt phenotyping algorithms for new contexts increasing efficiency and consistency of identifying patient populations from EHRs.
Using Machine Learning to Predict Antidepressant Treatment Outcome From Electronic Health Records
Xu, Zhenxing , Vekaria, Veer , Wang, Fei , Cukor, Judith, Adekkanattu, Prakash , Brandt, Pascal , Jiang, Guoqian , Kiefer, Richard C. , Pathak, Jyotishman , Vekaria, Veer , Su, Chang , Luo, Yuan , Rasmussen, Luke V. , Xu, Jie , Xiao, Yunyu , Alexopoulos, George S.

Psychiatric Research and Clinical Practice | March 27, 2023 | Volume: 5 | Issue: 4 | Pages: 118-125

10.1176/appi.prcp.20220015 Get It

Characterizing variability of electronic health record-driven phenotype definitions
Brandt, Pascal , Luo, Yuan , Pacheco, Jennifer A. , Walunas, Theresa L. , Håkonarson, Håkon , Liu, Cong , Walton, Nephi , Carrell, David , Crane, Paul K. , Chute, Christopher G. , Carroll, Robert J. , Denny, Joshua C. , Ramirez, Andrea H. , Wei, Wei‐Qi, Pathak, Jyoti , Wiley, Laura K. , Richesson, Rachel , Starren, Justin , Rasmussen, Luke V. , Brandt, Pascal S , Luo, Yuan , Pacheco, Jennifer A , Hakonarson, Hakon , Liu, Cong , Carrell, David S , Chute, Christopher G , Wiley, Laura K , Starren, Justin B , Rasmussen, Luke V , Denny, Joshua C , Richesson, Rachel L , Wei, Wei-Qi , Walunas, Theresa L , Kho, Abel , Hripcsak, George , Shang, Ning , Weng, Chunhua , Larson, Eric B. , Kullo, Iftikhar J. , Pathak, Jyoti

Journal of the American Medical Informatics Association | December 7, 2022 | Volume: 30 | Issue: 3 | Pages: 427-437

10.1093/jamia/ocac235 Get It

AbstractObjectiveThe aim of this study was to analyze a publicly available sample of rule-based phenotype definitions to characterize and evaluate the variability of logical constructs used.Materials and MethodsA sample of 33 preexisting phenotype definitions used in research that are represented using Fast Healthcare Interoperability Resources and Clinical Quality Language (CQL) was analyzed using automated analysis of the computable representation of the CQL libraries.ResultsMost of the phenotype definitions include narrative descriptions and flowcharts, while few provide pseudocode or executable artifacts. Most use 4 or fewer medical terminologies. The number of codes used ranges from 5 to 6865, and value sets from 1 to 19. We found that the most common expressions used were literal, data, and logical expressions. Aggregate and arithmetic expressions are the least common. Expression depth ranges from 4 to 27.DiscussionDespite the range of conditions, we found that all of the phenotype definitions consisted of logical criteria, representing both clinical and operational logic, and tabular data, consisting of codes from standard terminologies and keywords for natural language processing. The total number and variety of expressions are low, which may be to simplify implementation, or authors may limit complexity due to data availability constraints.ConclusionsThe phenotype definitions analyzed show significant variation in specific logical, arithmetic, and other operators but are all composed of the same high-level components, namely tabular data and logical expressions. A standard representation for phenotype definitions should support these formats and be modular to support localization and shared logic.
Design and validation of a FHIR-based EHR-driven phenotyping toolbox
Brandt, Pascal , Pacheco, Jennifer A. , Adekkanattu, Prakash , Sholle, Evan , Stone, Daniel J. , Knaack, David, Xu, Zhenxing , Wang, Fei , Jiang, Guoqian , Pathak, Jyotishman , Brandt, Pascal S , Sholle, Evan T , Knaack, David M, Peng, Yifan , Benda, Natalie C , Luo, Yuan , Rasmussen, Luke V , Pacheco, Jennifer A , Abedian, Sajjad , Xu, Jie , Luo, Yuan , Rasmussen, Luke V.

Journal of the American Medical Informatics Association | July 8, 2022 | Volume: 29 | Issue: 9 | Pages: 1449-1460

10.1093/jamia/ocac063 Get It

Abstract Objectives To develop and validate a standards-based phenotyping tool to author electronic health record (EHR)-based phenotype definitions and demonstrate execution of the definitions against heterogeneous clinical research data platforms. Materials and Methods We developed an open-source, standards-compliant phenotyping tool known as the PhEMA Workbench that enables a phenotype representation using the Fast Healthcare Interoperability Resources (FHIR) and Clinical Quality Language (CQL) standards. We then demonstrated how this tool can be used to conduct EHR-based phenotyping, including phenotype authoring, execution, and validation. We validated the performance of the tool by executing a thrombotic event phenotype definition at 3 sites, Mayo Clinic (MC), Northwestern Medicine (NM), and Weill Cornell Medicine (WCM), and used manual review to determine precision and recall. Results An initial version of the PhEMA Workbench has been released, which supports phenotype authoring, execution, and publishing to a shared phenotype definition repository. The resulting thrombotic event phenotype definition consisted of 11 CQL statements, and 24 value sets containing a total of 834 codes. Technical validation showed satisfactory performance (both NM and MC had 100% precision and recall and WCM had a precision of 95% and a recall of 84%). Conclusions We demonstrate that the PhEMA Workbench can facilitate EHR-driven phenotype definition, execution, and phenotype sharing in heterogeneous clinical research data environments. A phenotype definition that integrates with existing standards-compliant systems, and the use of a formal representation facilitates automation and can decrease potential for human error.
Under-specification as the Source of Ambiguity and Vagueness in Narrative Phenotype Algorithm Definitions
Yu, Jingzhi, Ghosh, Anika, Shang, Ning , Benoit, Barbara, Carrell, David, Carroll, Robert L., Gainer, Vivian S., Håkonarson, Håkon , Mentch, Frank , Murphy, Shawn N. , Peissig, Peggy , Ramirez, Andrea, Walton, Nephi , Wei, Wei‐Qi, Carroll, Robert J. , Hakonarson, Hakon , Yu, Jingzhi, Pacheco, Jennifer A. , Luo, Yuan , Weng, Chunhua , Carroll, Robert, Dikilitas, Ozan , Freimuth, Robert R. , Hripcsak, George , Kullo, Iftikhar J. , Rasmussen, Luke V.

No container title available | August 12, 2021 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-723873/v1 Get It

Abstract IntroductionCurrently, one of the commonly used methods for disseminating electronic health record (EHR)-based phenotype algorithms is providing a narrative description of the algorithm logic, often accompanied by flowcharts. A challenge with this mode of dissemination is the potential for under-specification in the algorithm definition, which leads to ambiguity and vagueness. MethodsThis study examines incidents of under-specification that occurred during the implementation of 34 narrative phenotyping algorithms in the electronic Medical Record and Genomics (eMERGE) network. We reviewed the online communication history between algorithm developers and implementers within the Phenotype Knowledge Base (PheKB) platform, where questions could be raised and answered regarding the intended implementation of a phenotype algorithm. ResultsWe developed a taxonomy of under-specification categories via an iterative review process between two groups of annotators. Under-specifications that lead to ambiguity and vagueness were consistently found across narrative phenotype algorithms developed by all involved eMERGE sites. Discussion & ConclusionOur findings highlight that under-specification is an impediment to the accuracy and efficiency of the implementation of current narrative phenotyping algorithms, and we propose approaches for mitigating these issues and improved methods for disseminating EHR phenotyping algorithms.
Infobuttons for Genomic Medicine: Requirements and Barriers
Connolly, John J. , Pet, Douglas , Peterson, Josh F. , Shirts, Brian H. , Starren, Justin , Walton, Nephi , Connolly, John J , Peterson, Josh F , Rasmussen, Luke V. , Fiol, Guilherme Del , Freimuth, Robert R. , Williams, Marc S , Taylor, Casey Overby

Applied Clinical Informatics | May 12, 2021 | Volume: 12 | Issue: 02 | Pages: 383-390

10.1055/s-0041-1729164 Get It

Abstract Objectives The study aimed to understand potential barriers to the adoption of health information technology projects that are released as free and open source software (FOSS). Methods We conducted a survey of research consortia participants engaged in genomic medicine implementation to assess perceived institutional barriers to the adoption of three systems: ClinGen electronic health record (EHR) Toolkit, DocUBuild, and MyResults.org. The survey included eight barriers from the Consolidated Framework for Implementation Research (CFIR), with additional barriers identified from a qualitative analysis of open-ended responses. Results We analyzed responses from 24 research consortia participants from 18 institutions. In total, 14 categories of perceived barriers were evaluated, which were consistent with other observed barriers to FOSS adoption. The most frequent perceived barriers included lack of adaptability of the system, lack of institutional priority to implement, lack of trialability, lack of advantage of alternative systems, and complexity. Conclusion In addition to understanding potential barriers, we recommend some strategies to address them (where possible), including considerations for genomic medicine. Overall, FOSS developers need to ensure systems are easy to trial and implement and need to clearly articulate benefits of their systems, especially when alternatives exist. Institutional champions will remain a critical component to prioritizing genomic medicine projects.
Data‐driven discovery of probable Alzheimer's disease and related dementia subphenotypes using electronic health records
Xu, Jie , Xu, Zhenxing , Adekkanattu, Prakash , Brandt, Pascal , Jiang, Guoqian , Kiefer, Richard C. , Luo, Yuan , Mao, Chengsheng , Zhang, Yiye , Isaacson, Richard , Pathak, Jyotishman , Brandt, Pascal S , Xu, Jie , Luo, Yuan , Wang, Fei “Fred” , Pacheco, Jennifer A. , Rasmussen, Luke V.

Learning Health Systems | September 24, 2020 | Volume: 4 | Issue: 4 | Pages: No page available

10.1002/lrh2.10246 Get It

AbstractIntroductionWe sought to assess longitudinal electronic health records (EHRs) using machine learning (ML) methods to computationally derive probable Alzheimer's Disease (AD) and related dementia subphenotypes.MethodsA retrospective analysis of EHR data from a cohort of 7587 patients seen at a large, multi‐specialty urban academic medical center in New York was conducted. Subphenotypes were derived using hierarchical clustering from 792 probable AD patients (cases) who had received at least one diagnosis of AD using their clinical data. The other 6795 patients, labeled as controls, were matched on age and gender with the cases and randomly selected in the ratio of 9:1. Prediction models with multiple ML algorithms were trained on this cohort using 5‐fold cross‐validation. XGBoost was used to rank the variable importance.ResultsFour subphenotypes were computationally derived. Subphenotype A (n = 273; 28.2%) had more patients with cardiovascular diseases; subphenotype B (n = 221; 27.9%) had more patients with mental health illnesses, such as depression and anxiety; patients in subphenotype C (n = 183; 23.1%) were overall older (mean (SD) age, 79.5 (5.4) years) and had the most comorbidities including diabetes, cardiovascular diseases, and mental health disorders; and subphenotype D (n = 115; 14.5%) included patients who took anti‐dementia drugs and had sensory problems, such as deafness and hearing impairment.The 0‐year prediction model for AD risk achieved an area under the receiver operating curve (AUC) of 0.764 (SD: 0.02); the 6‐month model, 0.751 (SD: 0.02); the 1‐year model, 0.752 (SD: 0.02); the 2‐year model, 0.749 (SD: 0.03); and the 3‐year model, 0.735 (SD: 0.03), respectively. Based on variable importance, the top‐ranked comorbidities included depression, stroke/transient ischemic attack, hypertension, anxiety, mobility impairments, and atrial fibrillation. The top‐ranked medications included anti‐dementia drugs, antipsychotics, antiepileptics, and antidepressants.ConclusionsFour subphenotypes were computationally derived that correlated with cardiovascular diseases and mental health illnesses. ML algorithms based on patient demographics, diagnosis, and treatment demonstrated promising results in predicting the risk of developing AD at different time points across an individual's lifespan.
Subphenotyping depression using machine learning and electronic health records
Xu, Zhenxing , Adekkanattu, Prakash , Bose, Budhaditya, Vekaria, Veer , Brandt, Pascal , Jiang, Guoqian, Kiefer, Richard C. , Luo, Yuan , Pathak, Jyotishman , Vekaria, Veer , Brandt, Pascal S , Xu, Jie , Luo, Yuan , Wang, Fei , Jiang, Guoqian , Pacheco, Jennifer A. , Rasmussen, Luke V. , Xu, Jie , Alexopoulos, George S.

Learning Health Systems | August 3, 2020 | Volume: 4 | Issue: 4 | Pages: No page available

10.1002/lrh2.10241 Get It

AbstractObjectiveTo identify depression subphenotypes from Electronic Health Records (EHRs) using machine learning methods, and analyze their characteristics with respect to patient demographics, comorbidities, and medications.Materials and MethodsUsing EHRs from the INSIGHT Clinical Research Network (CRN) database, multiple machine learning (ML) algorithms were applied to analyze 11 275 patients with depression to discern depression subphenotypes with distinct characteristics.ResultsUsing the computational approaches, we derived three depression subphenotypes: Phenotype_A (n = 2791; 31.35%) included patients who were the oldest (mean (SD) age, 72.55 (14.93) years), had the most comorbidities, and took the most medications. The most common comorbidities in this cluster of patients were hyperlipidemia, hypertension, and diabetes. Phenotype_B (mean (SD) age, 68.44 (19.09) years) was the largest cluster (n = 4687; 52.65%), and included patients suffering from moderate loss of body function. Asthma, fibromyalgia, and Chronic Pain and Fatigue (CPF) were common comorbidities in this subphenotype. Phenotype_C (n = 1452; 16.31%) included patients who were younger (mean (SD) age, 63.47 (18.81) years), had the fewest comorbidities, and took fewer medications. Anxiety and tobacco use were common comorbidities in this subphenotype.ConclusionComputationally deriving depression subtypes can provide meaningful insights and improve understanding of depression as a heterogeneous disorder. Further investigation is needed to assess the utility of these derived phenotypes to inform clinical trial design and interpretation in routine patient care.
Toward cross‐platform electronic health record‐driven phenotyping using Clinical Quality Language
Brandt, Pascal , Kiefer, Richard C. , Adekkanattu, Prakash , Xu, Jie , Xu, Zhenxing , Luo, Yuan , Jiang, Guoqian, Pathak, Jyotishman , Brandt, Pascal S , Xu, Jie , Luo, Yuan , Pacheco, Jennifer A. , Sholle, Evan , Ahmad, Faraz S. , Ancker, Jessica S. , Wang, Fei , Jiang, Guoqian , Rasmussen, Luke V.

Learning Health Systems | June 25, 2020 | Volume: 4 | Issue: 4 | Pages: No page available

10.1002/lrh2.10233 Get It

AbstractIntroductionElectronic health record (EHR)‐driven phenotyping is a critical first step in generating biomedical knowledge from EHR data. Despite recent progress, current phenotyping approaches are manual, time‐consuming, error‐prone, and platform‐specific. This results in duplication of effort and highly variable results across systems and institutions, and is not scalable or portable. In this work, we investigate how the nascent Clinical Quality Language (CQL) can address these issues and enable high‐throughput, cross‐platform phenotyping.MethodsWe selected a clinically validated heart failure (HF) phenotype definition and translated it into CQL, then developed a CQL execution engine to integrate with the Observational Health Data Sciences and Informatics (OHDSI) platform. We executed the phenotype definition at two large academic medical centers, Northwestern Medicine and Weill Cornell Medicine, and conducted results verification (n = 100) to determine precision and recall. We additionally executed the same phenotype definition against two different data platforms, OHDSI and Fast Healthcare Interoperability Resources (FHIR), using the same underlying dataset and compared the results.ResultsCQL is expressive enough to represent the HF phenotype definition, including Boolean and aggregate operators, and temporal relationships between data elements. The language design also enabled the implementation of a custom execution engine with relative ease, and results verification at both sites revealed that precision and recall were both 100%. Cross‐platform execution resulted in identical patient cohorts generated by both data platforms.ConclusionsCQL supports the representation of arbitrarily complex phenotype definitions, and our execution engine implementation demonstrated cross‐platform execution against two widely used clinical data platforms. The language thus has the potential to help address current limitations with portability in EHR‐driven phenotyping and scale in learning health systems.