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Background: Direct oral anticoagulants (DOACs) have the potential to improve stroke prevention among atrial fibrillation (AF) patients. We sought to determine if oral anticoagulation (OAC) treatment rates have increased since the approval of DOACs. Methods: We identified 6,688 patients with AF at an academic medical center from January 2008 to June 2015. We examined OAC prescription rates over time and according to CHA2DS2VASc score using multivariable Poisson regression models, with an interaction term between risk score and year of AF diagnosis. Results: Among 6,688 AF patients, 78% had CHA2DS2VASc scores ≥2, 51.6% of whom received an OAC prescription within 90 days of diagnosis. The OAC prescription rate was 47.8% in the pre-DOAC era and peaked at 56.4% in 2014. Relative to the pre-DOAC era, prescription rates increased in 2012 and leveled off thereafter. The prescription rate for the highest risk group was 58.5%, compared with 45.0% in patients with a CHA2DS2VASc score of 2 (p < 0.01). In the adjusted analysis, prescription rates were higher for the higher risk group (adjusted relative risk 1.24 for CHA2DS2VASc score 7-9 vs. 2, 95% CI 1.09-1.40). Conclusions: OAC treatment rates have increased since DOAC introduction, but substantial treatment gaps remain, specifically among the higher risk patients.

Introduction Improvements in multi-modal therapies have increased survival rates for older adults diagnosed with B-cell Non-Hodgkin Lymphoma (B-NHL). Despite this success, B-NHL survivors are at an increased risk for developing long-term and late complications of these therapies thereby compromising survival. Several studies have reported an increased risk in diabetes mellitus (DM) among long-term survivors of Hodgkin lymphoma and pediatric cancers. However, there are limited data on the risk of DM and its risk factors in older adults following treatment for B-NHL. Using data from the Utah Population Database, we evaluated the association between treatment for B-NHL and DM risk and furthermore compared this risk to a matched Utah general population. We hypothesized that the risk of DM among B-NHL survivors would be significantly increased compared to the general population. Methods Adult (age >18 years at diagnosis) survivors of primary B-NHL living in Utah at the time of diagnosis between 1997-2013, without a previous diagnosis of DM, and matched (1:4) to individuals without a prior history of DM from the Utah general population for birth year, birth state, and sex were included. New DM diagnoses were identified for all-time, 0-1, 1-5, and 5-10 years following a diagnosis of B-NHL. Adjusting for sex, race, baseline body mass index (BMI), and Charlson Comorbidity Index (CCI) scores, multivariate Cox proportional hazard analysis was performed to estimate the adjusted hazard ratio (aHR) of DM in B-NHL survivors compared with that in matched non-B-NHL individuals. Risk factors for DM were evaluated, including age at diagnosis, race, sex, BMI at baseline, family history of DM, cancer stage at diagnosis, and treatment modality. The risk of developing DM during all-time, 0 to 1, 1 to 5, and 5 to 10 years follow-up after adjusting for demographic variables was analyzed by age (< 40, 40-65, and >65 years) at diagnosis of B-NHL. Results The study population included 3,970 B-NHL survivors and 19,821 matched individuals from the general population. At the time of diagnosis, the majority of B-NHL patients were age 60 or greater (61.4%), had diffuse large B-cell lymphoma (46%) or follicular lymphoma (26.4%), distant cancer stage (50.1%), and received chemotherapy (27.5%). DM was diagnosed in 897 (22.6%) B-NHL survivors and 3,253 (16.4%) non-B-NHL adults. The majority in both groups were male (B-NHL: 55.5%; controls: 55.5%), white (B-NHL: 97.4%; controls: 93.8%), overweight [BMI 25-29.9 kg/m2 (B-NHL: 40.7%; controls: 40.6%)] or obese [BMI ≥30 kg/m2 (B-NHL: 21.8%; controls: 18.5%)]. The risk of developing DM among B-NHL survivors compared to the control group was significantly increased over all time (HR, 1.34; 95% CI 1.24 - 1.44) and the 0 to 1 year follow-up period (HR, 1.28; 95% CI 1.15 - 1.43)(Table 1). Multivariable analysis for DM risk showed that age 40-65 years and BMI ≥25 were factors independently associated with developing DM at all-time, 0 to 1, 1 to 5, and 5 to 10 years after diagnosis of B-NHL. Male sex and a family history of DM were significantly associated with development of DM during all time, 1 to 5, and 5 to 10 year follow-up periods. Distant cancer stage at diagnosis was a significant risk factor for DM at all time and 1 to 5 years while receipt of chemotherapy only or chemotherapy with radiation were significantly associated with development of DM at 5 to 10 years after diagnosis of B-NHL (estimated aHR and CIs are shown in Table 2). There was no significant association between race and the development of DM. Conclusion Adult survivors of B-NHL have an overall significantly higher risk of developing DM in the first year and over all time following a diagnosis of B-NHL compared to the general population. Age 40 to 65 years and BMI ≥25 were significant risk factors for DM across all follow-up periods while treatment with chemotherapy only or chemotherapy with radiation significantly increased the risk of DM 5-10 years after diagnosis of B-NHL. Race did not appear to be a risk factor for DM but this result may reflect the homogeneity of our study population. These findings contribute important information to the existing literature regarding the risk of developing DM in adult B-NHL survivors and provide foundation for the development of screening and management guidelines for DM in the B-NHL survivor population. Disclosures No relevant conflicts of interest to declare.

6051Background: Over 63,000 Americans develop head and neck cancer (HNC) yearly. The 5-year survival rate for HNC patients is 40-90%. HNC shares risk factors to cardiovascular disease (CVD), such a...

120 Background: There are an estimated 760,000 endometrial cancer survivors alive in the US today. We previously reported on increased heart disease (HD) risk among endometrial cancer survivors from our population-based cohort study. Although there are many risk prediction models for the risk of endometrial cancer, there are none to our knowledge for endometrial cancer survivors. Methods: We identified 2,994 endometrial cancer patients in the Utah Population Database, which links data from multiple statewide sources. We estimated hazard ratios with the Cox proportional hazards model for predictors of five-, ten- and fifteen-year risks. The Harrell’s C statistic was used to evaluate the model performance. We used 70% of the data randomly selected to develop the model and the rest of the data to validate the model. Results: A total of 1,591 patients were diagnosed with HD. Increased risks of HD among endometrial cancer patients were observed for older age, obesity at baseline, family history of HD, previous disease diagnosis (hypertension, diabetes, high cholesterol, COPD), distant stage, grade, histology, chemotherapy, and radiation therapy. The C-statistics for the risk prediction model were 0.69 for the hypothesized risk factors for HD, 0.56 for clinical factors, and 0.71 when statistically significant risk factors were included. With the final model selected, as one example, the absolute risks of HD were 17.6% at 5-years, 24.0% at 10-years and 32.0% at 15 years for a woman diagnosed with regional stage, grade I endometrial cancer in her fifties, was white, was obese at cancer diagnosis, had a family history of HD but no previous history of HD herself, had hypertension, but no history of diabetes or high cholesterol or COPD, and had radiation therapy treatment but no chemotherapy. The AUCs were 0.79 for the 5-year, 0.78 for the 10-year and 0.78 for the 15-year predictions. Conclusions: We developed the first risk prediction model for HD among endometrial cancer survivors within a population-based cohort study. Risk prediction models for cancer survivors are important in understanding long-term disease risks after cancer treatment is complete. Such models may contribute to management plans for treatment and individualized prevention efforts.

113 Background: In the United States, colorectal cancer is the fourth most common cancer and one of the leading causes of cancer death. Few studies have examined the relationship between colorectal cancer survivorship and long-term cardiovascular disease (CVD) risk. Methods: Individuals diagnosed with colorectal cancer were identified using the Utah Population Database. For a comparison group, up to 5 cancer-free individuals were matched by birth year, birth state, follow-up time and sex to each cancer case. For individuals with > 10 years of follow-up, we estimated CVD risk > 10 years after cancer diagnosis. Cox regression models were used to estimate hazard ratios (HR) and 95% Confidence Intervals. Results: Among 1,749 colorectal cancer survivors who had survived for at least 10 years, 1,001 (57.2%) were diagnosed with CVD > 10 years after cancer diagnosis. Compared to the general population, colorectal cancer survivors had an increased risk of CVD > 10 years after cancer diagnosis: HR = 2.84 (95% CI = 2.59, 3.11) for hypertension; HR = 2.66 (95% CI 2.37, 2.98) for diseases of the heart; HR = 3.91 (95% CI = 3.33, 4.58) for diseases of the arteries, arterioles and capillaries; HR = 2.58 (95% CI = 2.46, 2.99) for diseases of the veins and lymphatics; HR = 2.98 (95% CI = 2.36, 3.76) for cerebrovascular disease. Colorectal cancer survivors with ≥1 comorbidity had an increased risk of CVD > 10 years after cancer diagnosis compared to survivors with no comorbidities (HR = 1.7, 95% CI = 1.49, 1.95). Colorectal cancer survivors who were ≥65 years had an increased risk of CVD > 10 years after cancer diagnosis. Colorectal cancer survivors who were obese at the time of diagnosis had an increased risk of CVD > 10 years after cancer diagnosis when compared to survivors with normal BMIs (HR = 1.25; 95% CI = 1.06, 1.49). Conclusions: Compared to the general population, colorectal cancer survivors had an increased risk of CVD during the > 10 year follow-up period. Within colorectal cancer survivors, there was an increased risk of CVD for those that were older, had ≥1 comorbidity and were obese. The increased risk of CVD among survivors may be attributable to the lifestyle risk factors shared by colorectal cancer and CVD.

10073 Background: In the US, there are approximately 235,200 ovarian cancer survivors today. Five-year survival for ovarian cancer has increased from 36% for women who were diagnosed in 1975-1977 to 46% for women diagnosed between 2005-2011. Long term follow-up studies among ovarian cancer survivors are uncommon and late effects have not been well characterized in a population-based cohort. Although genitourinary complications during treatment are well known, long term impacts need to be investigated. Methods: A total of 602 first primary invasive ovarian cancer cases diagnosed between 1996-2012 who survived for > 5 years were identified in the Utah Population Database and compared to a general population cohort of women. Genitourinary disease diagnoses were identified through ICD codes from hospital electronic medical records and statewide ambulatory surgery and inpatient data. Cox regression models were used to estimate hazard ratios for disease risks by time since cancer diagnosis with adjustments on matching factors, baseline BMI, baseline Charlson Comorbidity Index (CCI), and race. Results: The overall risk of genitourinary diseases for ovarian cancer patients in comparison to the general population cohort was 1.51 (95%CI = 1.30-1.74) 5-10 years after cancer diagnosis. Approximately 54.6% of ovarian cancer survivors were diagnosed with a genitourinary disease 5-10 years after cancer diagnosis. The most common genitourinary diseases among the ovarian cancer survivors were urinary tract infections (10.1%), acute renal failure (5.5%), and chronic kidney disease (4.4%). The greatest risks were observed for hydronephrosis (HR = 10.65, 95%CI = 3.68-30.80), pelvic peritoneal adhesions (HR = 5.81, 95%CI = 1.11-30.39), cystitis and urethritis (HR = 2.67, 95%CI = 1.21-6.38), and acute renal failure (HR = 2.30, 95%CI = 1.36-3.88). Conclusions: Ovarian cancer survivors experience increased risks of various genitourinary diseases in the 5-10 year period following cancer diagnosis. Understanding the multimorbidity trajectory among ovarian cancer survivors is of vital importance to improve their clinical care after cancer diagnosis and allow for increased attention to these potential late effects.

137 Background: Sites of head and neck are associated with chewing, swallowing and speaking. As for treatment of head and neck cancer (HNC), we have to consider organ preservation as well as clinical outcomes. Although non-surgical treatments have been preferred in recent years, complications after treatment have been a concern. The aim of this study was to evaluate the late effects in a cohort of HNC survivors in Utah compared to a matched cohort of cancer free individuals. Methods: Up to 5 cancer free individuals were matched to each HNC survivor on birth year, sex, birth state, and follow up time. Electronic medical records and statewide ambulatory and inpatient surgery data were used to identify late effects over two time periods: 1-5 and 5-10 years after cancer diagnosis. Cox proportional hazards models were used to estimate the risks of late effects. We adjusted for matching factors, race and number of hospital visit. Results: In this study, 2,432 HNC survivors and 12,149 matched controls were enrolled. More than 80% cases had loco-regional disease and a histological type of squamous cell carcinoma. Hazard ratio (HR) for second primary HNC was notably increased among HNC survivors for both 1-5 years (HR: 1498.46; 95% confidence interval (CI), 158.58-14159.69) and 5-10 years (HR: 1509.62; 95% CI, 147.94-15404.15) post cancer diagnosis. And, HRs for respiratory disease, including respiratory system, lung cancer and pneumoniae, were also increased among HNC survivors for both 1-5 years and 5-10 years post cancer diagnosis. As for hearing loss, HNC survivors had a increased HR for 1-5 years post cancer diagnosis (HR: 5.90; 95% CI, 2.67-13.01) and this association was consistent for 5-10 years post cancer diagnosis (HR: 5.01; 95% CI, 2.06-12.18). Conclusions: In this study, we found HNC survivors have notable associations with second primary HNC, smoking related respiratory disease, and hearing loss which might be associated with chemotherapy when compared to cancer free subjects.

111 Background: Thyroid cancer is the most rapidly increasing cancer with over 600,000 thyroid cancer survivors in the U.S. Thyroid cancer affects a young population and the 5-year survival rate is over 98%. There have been few studies on the late effects of thyroid cancer, especially in younger populations. The aim of this study was to examine if thyroid cancer survivors diagnosed < 40 years experience greater risks of late effects than older age groups for diseases associated with aging. Methods: Up to 5 cancer free individuals were matched to each thyroid cancer survivor based on birth year, sex, birth state, and follow up time from case diagnosis date, within the Utah Population Database. Electronic medical records, statewide ambulatory surgery and inpatient discharge data were used to identify late effects stratified over three time periods: 1-5, 5-10, and > 10 years after cancer diagnosis. Cox proportional hazards models were used to estimate hazard ratios (HR) with adjustment on matching factors, race, BMI at diagnosis, and Charlson Comorbidity Index at diagnosis. Results: There were 4,060 thyroid cancer survivors and 18,557 matched cancer free individuals (1,407 cases diagnosed ages < 40 years, 2,076 cases diagnosed ages 40-65 years). The risk for hypertension was significantly increased in both younger (HR = 1.54, 95%CI = 1.18, 2.01) and older patients (HR = 1.30, 95%CI = 1.11, 1.53) > 10 years after cancer diagnosis. For heart disease, increased risks persisted for the young patients > 10 years after cancer diagnosis for heart valve disorders (HR = 2.43, 95%CI = 1.36, 4.33) and for peri-, endo- or myocarditis (HR = 5.12, 95%CI = 1.04, 25.14), while corresponding HRs for the older age group did not suggest increased risks. For osteoporosis, the younger patients had a higher risk (HR = 8.77, 95%CI = 3.18, 24.18) than the older population (HR = 2.55, 95%CI = 2.07, 3.13) 1-5 years after cancer diagnosis. Conclusions: Thyroid cancer survivors diagnosed at < 40 years had increased risks for diseases associated with aging such as hypertension, heart disease, and osteoporosis. As thyroid cancer affects a young population, understanding what late effects may result from the treatment can lead to better surveillance and disease management.

131 Background: Endometrial cancer is the second most common cancer among female cancer survivors in the US, with an estimated 757,000 endometrial cancer survivors in 2016. Cardiovascular disease is the leading cause of death among endometrial cancer survivors. Cardiovascular disease risk may be increased among endometrial cancer survivors due to shared risk factors such as obesity or because of cancer treatment. Because of the high overall survival rate and the large number of endometrial cancer survivors, studies that examine late effects among endometrial cancer survivors are critical. Methods: Cohorts of 3,337 endometrial cancer survivors diagnosed between 1997 and 2012, and 19,420 age-matched cancer-free women were identified using the Utah Population Database. All ICD-9 diagnosis codes were collected from the state’s two largest healthcare systems and statewide ambulatory surgery and inpatient visits. Diagnoses were collapsed into cardiovascular system disorders according to the Healthcare Cost and Utilization Project’s Clinical Classification Software. Cox regression models were used to estimate hazard ratios (HR) at 1-5 years and 5-10 years after cancer diagnosis. Models were adjusted for race/ethnicity, baseline BMI, and baseline Charlson Comorbidity Index. Results: Approximately 89.4% of cancer cases were diagnosed with stage I or stage II disease. At 1-5 years after diagnosis, the highest risks among endometrial cancer survivors were observed for phlebitis and thrombophlebitis (HR: 3.36, 99% CI: 1.96-5.77), lymphatic diseases (HR: 1.89, 99% CI: 1.64-2.19), pulmonary heart disease (HR: 1.82, 99% CI: 1.36-2.43), hypotension (HR: 1.64, 99% CI: 1.18-2.29), and atrial fibrillation (HR: 1.61, 99% CI: 1.25-2.06). At 5-10 years, elevated risk persisted for these and 17 out of 66 additional outcomes among the endometrial cancer survivors. Conclusions: Endometrial cancer survivors in this population are at higher risk for various long term cardiovascular outcomes compared to cancer-free women. This study presents sufficient evidence to suggest that increased monitoring is necessary for women diagnosed with endometrial cancer in the first several years after diagnosis, and out to ten years as well.

The involvement of the right main bronchus (RMB) along with the upper lobe bronchus and bronchus intermedius by malignant tumor is frequently encountered. However, the use of a stent for palliation of airway stenosis of the RMB might obstruct upper lobe orifice and pose complications such as atelectasis or recurrent pneumonia. We report the use of modified Montgomery T tube in a 78-year-old man with neoplasm of the RMB by placing the tracheostomy arm of the T tube in the upper lobe bronchus to maintain its patency.

The diagnosis of unruptured pulmonary hydatidosis is based on classical radiologic features. However, ruptured or complicated hydatid cysts alter the radiologic signs and lead to delayed or incorrect diagnosis. The role of flexible bronchoscopy was assessed as a diagnostic tool in the evaluation in such cases. Between 2002 and 2008, 14 patients (7 female, 7 male), aged between 18 and 55 years, with a mean age of 36 years, were evaluated for pulmonary hydatidosis. Clinical history, radiologic findings, and other investigations of the patients were reviewed retrospectively at a tertiary referral center. All 14 patients were symptomatic, with cough, hemoptysis, and chest pain being the most common symptoms. Seven patients had right lung involvement, whereas 6 patients had left-sided predilection, and the remainder presented with pleural disease. At flexible bronchoscopy, white glistening membrane could be observed in 9 patients, whereas cytologic evaluation of bronchial washing did not show cuticular particles, degenerated scoleces, or hooklets in any of the cases. Twelve patients underwent uneventful surgical intervention. Surgical specimens showed 2 unruptured pulmonary hydatid cysts (uncomplicated), 1 pleural hydatid, and 9 ruptured pulmonary hydatid cysts. Of the 9 ruptured hydatid cyst cases, evidence of fungal (aspergillus) colonization, bacterial infection, and coexistent tuberculous granuloma was reported in 2 cases each. Bronchoscopy is an important tool that aids in confirming the diagnosis before surgery, especially in complicated pulmonary hydatidosis. Special stains for cytologic specimen should be used if the possibility of ruptured hydatid is thought to improve the diagnostic yield. The histopathology of the surgical specimen should be reviewed for associated secondary infection and fungal colonization.

Background Retrospective research requires longitudinal data, and repositories derived from electronic health records (EHR) can be sources of such data. With Health Information Technology for Economic and Clinical Health (HITECH) Act meaningful use provisions, many institutions are expected to adopt EHRs, but may be left with large amounts of financial and historical clinical data, which can differ significantly from data obtained from newer systems, due to lack or inconsistent use of controlled medical terminologies (CMT) in older systems. We examined different approaches for semantic enrichment of financial data with CMT, and integration of clinical data from disparate historical and current sources for research. Methods Snapshots of financial data from 1999, 2004 and 2009 were mapped automatically to the current inpatient pharmacy catalog, and enriched with RxNorm. Administrative metadata from financial and dispensing systems, RxNorm and two commercial pharmacy vocabularies were used to integrate data from current and historical inpatient pharmacy modules, and the outpatient EHR. Data integration approaches were compared using percentages of automated matches, and effects on cohort size of a retrospective study. Results During 1999-2009, 71.52%-90.08% of items in use from the financial catalog were enriched using RxNorm; 64.95%-70.37% of items in use from the historical inpatient system were integrated using RxNorm, 85.96%-91.67% using a commercial vocabulary, 87.19%-94.23% using financial metadata, and 77.20%-94.68% using dispensing metadata. During 1999-2009, 48.01%-30.72% of items in use from the outpatient catalog were integrated using RxNorm, and 79.27%-48.60% using a commercial vocabulary. In a cohort of 16304 inpatients obtained from clinical systems, 4172 (25.58%) were found exclusively through integration of historical clinical data, while 15978 (98%) could be identified using semantically enriched financial data. Conclusions Data integration using metadata from financial/dispensing systems and pharmacy vocabularies were comparable. Given the current state of EHR adoption, semantic enrichment of financial data and integration of historical clinical data would allow the repurposing of these data for research. With the push for HITECH meaningful use, institutions that are transitioning to newer EHRs will be able to use their older financial and clinical data for research using these methods.

Adsorption of fibrinogen to the monolayers of mixed lipids, dipalmitoyl phosphatidyl choline (DPPC) and eicosylamine (EA) was measured at a surface pressure of 20 mN/m by an in situ surface plasmon resonance technique. Pressure–area isotherms of DPPC + EA mixtures on water and buffer subphases indicated good lipid miscibility and some contraction of the monolayers at intermediate and higher surface pressures. Surface electric potential of the DPPC + EA monolayers showed excess values for intermediate DPPC:EA ratios. Fibrinogen adsorption and its adsorption rates from a dilute solution (0.03 mg/ml) were proportional to the fraction of EA in the monolayer indicating that protein binding was primarily driven by electrostatic interactions between positive EA charges in the monolayer and a net negative protein charge. At a higher protein concentration (0.06 mg/ml) both the fibrinogen adsorbed amount and its maximum adsorption rate showed excess values relative to the pure EA for 1:1, 2:1 and 3:1 DPPC + EA monolayers. This excess adsorption could be explained, in part, by the contraction of the monolayers with intermediate DPPC:EA ratios which resulted in an excess surface electric potential.

Summary Objectives: We investigated the suitability of representing discrete genetic test results in the electronic health record (EHR) as individual single nucleotide polymorphisms (SNPs) and as alleles, using the CYP2C9 gene and its polymorphic states, as part of a pilot study. The purpose of our investigation was to determine the appropriate level of data abstraction when reporting genetic test results in the EHR that would allow meaningful interpretation and clinical decision support based on current knowledge, while retaining sufficient information in order to enable reinterpretation of the results in the context of future discoveries. Methods: Based on the SNP & allele models, we designed two separate lab panels within the laboratory information system, one containing SNPs and the other containing alleles, built separate rules in the clinical decision support system based on each model, and evaluated the performance of these rules in an EHR simulation environment using real-world scenarios. Results: Although decision-support rules based on allele model required significantly less computational time than rules based on SNP model, no difference was observed on the total time taken to chart medication orders between rules based on these two models. Conclusions: Both, SNP- and allele-based models, can be used effectively for representing genetic test results in the EHR without impacting clinical decision support systems. While storing and reporting genetic test results as alleles allow for the construction of simpler decision-support rules, and make it easier to present these results to clinicians, SNP-based model can retain a greater amount of information that could be useful for future reinterpretation.

The University of Utah has initiated the design and implementation of an innovative data and knowledge management informatics platform for the new Center for Clinical and Translational Science. The main component of the platform is described, along with preliminary project objectives and current status.

We find accurate approximations for the expected number of three-cycles and unchorded four-cycles under a stochastic distribution for graphs that has been proposed for modelling yeast two-hybrid protein-protein interaction networks. We show that unchorded four-cycles are characteristic motifs under this model and that the count of unchorded four-cycles in the graph is a reliable statistic on which to base parameter estimation. Finally, we test our model against a range of experimental data, obtain parameter estimates from these data and investigate possible improvements in the model. Characterization of this model lays the foundation for its use as a prior distribution in a Bayesian analysis of yeast two-hybrid networks that can potentially aid in identifying false-positive and false-negative results.

Background Selecting patient cohorts is a critical, iterative, and often time-consuming aspect of studies involving human subjects; informatics tools for helping streamline the process have been identified as important infrastructure components for enabling clinical and translational research. We describe the evaluation of a free and open source cohort selection tool from the Informatics for Integrating Biology and the Bedside (i2b2) group: the i2b2 hive. Methods Our evaluation included the usability and functionality of the i2b2 hive using several real world examples of research data requests received electronically at the University of Utah Health Sciences Center between 2006 - 2008. The hive server component and the visual query tool application were evaluated for their suitability as a cohort selection tool on the basis of the types of data elements requested, as well as the effort required to fulfill each research data request using the i2b2 hive alone. Results We found the i2b2 hive to be suitable for obtaining estimates of cohort sizes and generating research cohorts based on simple inclusion/exclusion criteria, which consisted of about 44% of the clinical research data requests sampled at our institution. Data requests that relied on post-coordinated clinical concepts, aggregate values of clinical findings, or temporal conditions in their inclusion/exclusion criteria could not be fulfilled using the i2b2 hive alone, and required one or more intermediate data steps in the form of pre- or post-processing, modifications to the hive metadata, etc. Conclusion The i2b2 hive was found to be a useful cohort-selection tool for fulfilling common types of requests for research data, and especially in the estimation of initial cohort sizes. For another institution that might want to use the i2b2 hive for clinical research, we recommend that the institution would need to have structured, coded clinical data and metadata available that can be transformed to fit the logical data models of the i2b2 hive, strategies for extracting relevant clinical data from source systems, and the ability to perform substantial pre- and post-processing of these data.