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Dive into the research topics where A. James O'Malley is active.

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Featured researches published by A. James O'Malley.


The Lancet | 2015

Social network targeting to maximise population behaviour change: a cluster randomised controlled trial

David A. Kim; Alison R. Hwong; Derek Stafford; D. Alex Hughes; A. James O'Malley; James H. Fowler; Nicholas A. Christakis

BACKGROUNDnInformation and behaviour can spread through interpersonal ties. By targeting influential individuals, health interventions that harness the distributive properties of social networks could be made more effective and efficient than those that do not. Our aim was to assess which targeting methods produce the greatest cascades or spillover effects and hence maximise population-level behaviour change.nnnMETHODSnIn this cluster randomised trial, participants were recruited from villages of the Department of Lempira, Honduras. We blocked villages on the basis of network size, socioeconomic status, and baseline rates of water purification, for delivery of two public health interventions: chlorine for water purification and multivitamins for micronutrient deficiencies. We then randomised villages, separately for each intervention, to one of three targeting methods, introducing the interventions to 5% samples composed of either: randomly selected villagers (n=9 villages for each intervention); villagers with the most social ties (n=9); or nominated friends of random villagers (n=9; the last strategy exploiting the so-called friendship paradox of social networks). Participants and data collectors were not aware of the targeting methods. Primary endpoints were the proportions of available products redeemed by the entire population under each targeting method. This trial is registered with ClinicalTrials.gov, number NCT01672580.nnnFINDINGSnBetween Aug 4, and Aug 14, 2012, 32 villages in rural Honduras (25-541 participants each; total study population of 5773) received public health interventions. For each intervention, nine villages (each with 1-20 initial target individuals) were randomised, using a blocked design, to each of the three targeting methods. In nomination-targeted villages, 951 (74·3%) of 1280 available multivitamin tickets were redeemed compared with 940 (66·2%) of 1420 in randomly targeted villages and 744 (61·0%) of 1220 in indegree-targeted villages. All pairwise differences in redemption rates were significant (p<0·01) after correction for multiple comparisons. Targeting nominated friends increased adoption of the nutritional intervention by 12·2% compared with random targeting (95% CI 6·9-17·9). Targeting the most highly connected individuals, by contrast, produced no greater adoption of either intervention, compared with random targeting.nnnINTERPRETATIONnIntroduction of a health intervention to the nominated friends of random individuals can enhance that interventions diffusion by exploiting intrinsic properties of human social networks. This method has the additional advantage of scalability because it can be implemented without mapping the network. Deployment of certain types of health interventions via network targeting, without increasing the number of individuals targeted or the resources used, could enhance the adoption and efficiency of those interventions, thereby improving population health.nnnFUNDINGnNational Institutes of Health, The Bill & Melinda Gates Foundation, Star Family Foundation, and the Canadian Institutes of Health Research.


Health Services Research | 2016

Green House Adoption and Nursing Home Quality

Christopher C. Afendulis; Daryl J. Caudry; A. James O'Malley; Peter Kemper; David C. Grabowski

OBJECTIVEnTo evaluate the impact of the Green House (GH) model on nursing home resident-level quality of care measures.nnnDATA SOURCES/STUDY SETTINGnResident-level minimum data set (MDS) assessments merged with Medicare inpatient claims for the period 2005 through 2010.nnnSTUDY DESIGNnUsing a difference-in-differences framework, we compared changes in care quality and outcomes in 15 nursing homes that adopted the GH model relative to changes over the same time period in 223 matched nursing homes that had not adopted the GH model.nnnPRINCIPAL FINDINGSnFor individuals residing in GH homes, adoption of the model lowered readmissions and several MDS measures of poor quality, including bedfast residents, catheter use, and pressure ulcers, but these results were not present across the entire GH organization, suggesting possible offsetting effects for residents of non-GH legacy units within the GH organization.nnnCONCLUSIONSnGH adoption led to improvement in rehospitalizations and certain nursing home quality measures for individuals residing in a GH home. The absence of evidence of a decline in other clinical quality measures in GH nursing homes should reassure anyone concerned that GH might have sacrificed clinical quality for improved quality of life.


Progress in Community Health Partnerships | 2009

Strategies to Improve Chronic Disease Management in Seven Metro Boston Community Health Centers

Chima D. Ndumele; Beverley E. Russell; John Z. Ayanian; Bruce E. Landon; Thomas Keegan; A. James O'Malley; LeRoi S. Hicks

Background: The Community, Health Center, and Academic Medicine Partnership Project (CHAMPP) is a partnership between medical researchers, community health centers (CHCs), and a community advisory committee focused on reducing cardiovascular morbidity related to hypertension and diabetes for non-Hispanic Black and Hispanic populations in Boston, Massachusetts. Objective: We conducted site visits at seven participating CHCs, located in Boston. The visits were to solicit health center staff opinions about site-specific barriers and enabling factors for optimum preventative cardiovascular care for racial/ethnic minority patients receiving hypertension and diabetes care at their centers. Methods: Site visits included a tour of each health center and a series of directed interviews with center personnel. Site visit notes were reviewed to identify themes that emerged during the course of each site visit. A summary matrix was developed for each health center, which included information regarding the most salient and persistent themes of the visit. Results: Site visits uncovered several patient-, provider-, CHC-, and community-based factors that either facilitate or hinder optimal care of chronic disease patients. Commonly referenced barriers included the need for improved patient adherence to provider recommendations; insufficient time for providers to address complex health issues presented by patients and the need for a broader range of healthier food options in surrounding communities. Interactive patient groups and community health workers (CHWs) have been well received when implemented. Conclusion: Recommendations included adopting case management as a part of usual care for chronic disease patients; additionally, widespread implementation of CHWs may to provide a platform for more comprehensive care for patients.


Health Services Research | 2016

The Impact of Green House Adoption on Medicare Spending and Utilization.

David C. Grabowski; Christopher C. Afendulis; Daryl J. Caudry; A. James O'Malley; Peter Kemper

OBJECTIVEnTo evaluate the impact of the Green House (GH) model of nursing home care on Medicare acute hospital, other hospital, skilled nursing facility, and hospice spending and utilization.nnnDATA SOURCES/STUDY SETTINGnMedicare claims and enrollment data from 2005 through 2010 merged with resident-level minimum data set (MDS) assessments.nnnSTUDY DESIGNnUsing a difference-in-differences framework, we compared Medicare Part A and hospice expenditures and utilization in 15 nursing homes that adopted the GH model relative to changes over the same time period in 223 matched nonadopting nursing homes. We applied the same method for residents of GH homes and for residents of legacy homes, the original nursing homes that stay open alongside the GH home(s).nnnPRINCIPAL FINDINGSnThe adoption of GH had no detectable impact on Medicare Part A (plus hospice) spending and utilization across all residents living in the nursing home. When we analyzed residents living in GH homes and legacy units separately, however, we found that the adoption of the GH model reduced overall annual Medicare Part A spending by


Statistics in Medicine | 2018

Analysis of the U.S. patient referral network: Analyze US Patient Referral Network and its Relationship to Healthcare

Chuankai An; A. James O'Malley; Daniel N. Rockmore; Corey D. Stock

7,746 per resident, although this appeared to be partially offset by an increase in spending in legacy homes.nnnCONCLUSIONSnTo the extent that the GH model reduces Medicare spending, adopting nursing homes do not receive any of the related Medicare savings under traditional payment mechanisms. New approaches that are currently being developed and piloted, which better align financial incentives for providers and payers, could incentivize greater adoption of the GH model.


BMJ Open | 2017

Assessing medical student knowledge and attitudes about shared decision making across the curriculum: protocol for an international online survey and stakeholder analysis

Durand; Renata West Yen; Paul J. Barr; N. Cochran; J.W. Aarts; F. Legare; Malcolm Reed; A. James O'Malley; P. Scalia; G.P. Guerard; Glyn Elwyn

In this paper, we analyze the US Patient Referral Network (also called the Shared Patient Network) and various subnetworks for the years 2009 to 2015. In these networks, two physicians are linked if a patient encounters both of them within a specified time interval, according to the data made available by the Centers for Medicare and Medicaid Services. We find power law distributions on most state-level data as well as a core-periphery structure. On a national and state level, we discover a so-called small-world structure as well as a gravity law of the type found in some large-scale economic networks. Some physicians play the role of hubs for interstate referral. Strong correlations between certain network statistics with health care system statistics at both the state and national levels are discovered. The patterns in the referral network evinced using several statistical analyses involving key metrics derived from the network illustrate the potential for using network analysis to provide new insights into the health care system and opportunities or mechanisms for catalyzing improvements.


Annals of Vascular Surgery | 2017

Comparison of Endovascular Stent Grafts for Abdominal Aortic Aneurysm Repair in Medicare Beneficiaries

Dominique B. Buck; Peter A. Soden; Sarah E. Deery; Sara L. Zettervall; Klaas H.J. Ultee; Bruce E. Landon; A. James O'Malley; Marc L. Schermerhorn

Introduction Shared decision making (SDM) is a goal of modern medicine; however, it is not currently embedded in routine care. Barriers include clinicians’ attitudes, lack of knowledge and training and time constraints. Our goal is to support the development and delivery of a robust SDM curriculum in medical education. Our objective is to assess undergraduate medical students’ knowledge of and attitudes towards SDM in four countries. Methods and analysis The first phase of the study involves a web-based cross-sectional survey of undergraduate medical students from all years in selected schools across the United States (US), Canada and undergraduate and graduate students in the Netherlands. In the United Kingdom (UK), the survey will be circulated to all medical schools through the UK Medical School Council. We will sample students equally in all years of training and assess attitudes towards SDM, knowledge of SDM and participation in related training. Medical students of ages 18 years and older in the four countries will be eligible. The second phase of the study will involve semistructured interviews with a subset of students from phase 1 and a convenience sample of medical school curriculum experts or stakeholders. Data will be analysed using multivariable analysis in phase 1 and thematic content analysis in phase 2. Method, data source and investigator triangulation will be performed. Online survey data will be reported according to the Checklist for Reporting the Results of Internet E-Surveys. We will use the COnsolidated criteria for REporting Qualitative research for all qualitative data. Ethics and dissemination The study has been approved for dissemination in the US, the Netherlands, Canada and the UK. The study is voluntary with an informed consent process. The results will be published in a peer-reviewed journal and will help inform the inclusion of SDM-specific curriculum in medical education worldwide.


Journal of the American Geriatrics Society | 2014

Effect of part D coverage restrictions for antidepressants, antipsychotics, and cholinesterase inhibitors on related nursing home resident outcomes

David G. Stevenson; A. James O'Malley; Stacie B. Dusetzina; Susan L. Mitchell; Barbara J. Zarowitz; Michael E. Chernew; Joseph P. Newhouse; Haiden A. Huskamp

BACKGROUNDnIncreased renal complications have been suggested with suprarenal stent grafts, but long-term analyses have been limited. Therefore, the purpose of this study was to evaluate the effect of endograft choice on perioperative and long-term outcomes.nnnMETHODSnWe compared Medicare beneficiaries undergoing endovascular abdominal aortic aneurysms repair from 2005 to 2008 with endografts with infrarenal fixation and a single docking limb (AneuRx, Excluder) to those with suprarenal fixation and 2 docking limbs (Zenith), or a unibody configuration (Powerlink). Propensity score weighting accounted for differences in patient characteristics among the different graft formations, and perioperative mortality, complications, and length of stay and 4-year rates of survival, rupture, and reintervention were compared.nnnRESULTSnForty-six thousand one hundred seventy-one Medicare beneficiaries were identified including 11,002 (24%) with suprarenal fixation, 32,909 (71%) with infrarenal fixation, and 2,260 (5%) with a unibody graft. After propensity score weighting, there were no significant differences in patients baseline clinical and demographic characteristics. The suprarenal fixation patients had higher rates of perioperative mortality (1.7% vs. 1.3%, Pxa0<xa00.01), renal failure (6.0% vs. 4.7%, Pxa0<xa00.001), and mesenteric ischemia (0.7% vs. 0.4%, Pxa0<xa00.01) and longer length of stay (3.4xa0days vs. 3.0xa0days, Pxa0<xa00.001) compared with patients with infrarenal fixation. Unibody grafts had higher rates of renal failure (5.9% vs. 4.7%, Pxa0<xa00.001), mesenteric ischemia (1.0% vs. 0.4%, Pxa0<xa00.001), and conversion to open repair (0.7% vs. 0.1%, Pxa0<xa00.001) compared to those with infrarenal fixation and single docking limbs. At 4 years, mortality remained slightly higher with suprarenal compared to infrarenal fixation (30% vs. 29%, Pxa0=xa00.047), although these patients had fewer conversions to open repair (0.6% vs. 0.9%, Pxa0=xa00.03) and aneurysm-related reinterventions (10% vs. 12%, Pxa0<xa00.01). At 4 years, unibody grafts had more aneurysm-related interventions compared to infrarenal fixation grafts (15% vs. 12%, Pxa0<xa00.01) but fewer conversions to open repair (0.4% vs. 0.9%, Pxa0=xa00.02). Late rupture did not differ among the groups.nnnCONCLUSIONSnCompared to infrarenal fixation devices, patients who underwent EVAR with suprarenal fixation had higher perioperative mortality and renal complications but fewer reinterventions including conversion, while the unibody graft had more perioperative complications and aneurysm-related reinterventions, but fewer conversions to open repair. Although these differences could be explained by selection bias, these data suggest that further comparative effectiveness analyses should be performed to understand the outcomes following EVAR with suprarenal fixation and unibody grafts.


Journal of Vascular Surgery | 2018

Use of an Assistant Surgeon Does not Mitigate the Effect of Lead Surgeon Volume on Outcomes Following Open Repair of Intact Abdominal Aortic Aneurysms

Sarah E. Deery; Thomas F. O'Donnell; Sara L. Zettervall; Jeremy D. Darling; Katie E. Shean; A. James O'Malley; Bruce E. Landon; Marc L. Schermerhorn

In 2006, Medicare Part D transitioned prescription drug coverage for dual‐eligible nursing home residents from Medicaid to Medicare and randomly assigned them to Part D prescription drug plans (PDPs). Because PDPs may differ in coverage, plans may be more or less generous for drugs that an individual is taking. Taking advantage of the fact that randomization mitigates potential selection bias common in observational studies, this study sought to assess the effect of PDP coverage on resident outcomes for three medication classes—antidepressants, antipsychotics, and cholinesterase inhibitors.


Journal of Vascular Surgery | 2018

A comparative analysis of long-term mortality after carotid endarterectomy and carotid stenting

Jesse A. Columbo; Pablo Martínez-Camblor; Todd A. MacKenzie; Ravinder Kang; Spencer W. Trooboff; Philip P. Goodney; A. James O'Malley

or directional side branches. Early experience with the use of inner branches for visceral arteries in F/BEVAR is described. Methods: All consecutive patients treated by F/BEVAR for complex abdominal aortic aneurysm (AAA) or thoraco-abdominal aneurysm (TAAA) using stent grafts with inner branches were included. Data were collected prospectively. Results: Thirty-two patients (28 male, mean age 71.6 6 8.3 years) were included. Seven (21.9%) patients had a complex AAA and 25 (78.1%) had a TAAA. A stent graft with inner branches only was used in four (12.5%) patients. The remaining 28 (87.5%) patients received a stent graft with fenestrations and inner branches. In total 52 vessels were targeted with inner branches. Technical success was achieved in all 32 (100%) patients. All 38 inner branch target vessels in grafts including fenestrations and inner branches were instantly catheterised (<1 minute), whereas catheterisation of target vessels in “inner branch only” grafts proved more difficult (<1 minute, n = 3; 1e3 min, n = 4; and >3 min, n = 7). The 30 day operative mortality was 3.1% (1/32). Estimated survival at 1 year was 80.0% 6 8.3%. During follow-up, four renal inner branches occluded in three patients. The estimated inner branch target vessel stent patency at 1 year was 91.9 6 4.5%. The estimated freedom from re-intervention at 1 year was 78.4% 6 8.9%. Conclusions: Early data suggest that visceral inner branches might represent a feasible third option to address selected target vessels in F/BEVAR. Stent grafts with inner branch(es) in combination with fenestrations seem to be a better configuration than stent grafts with inner branches alone. Durability of the inner branch design needs further investigation.

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Glyn Elwyn

The Dartmouth Institute for Health Policy and Clinical Practice

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Marc L. Schermerhorn

Beth Israel Deaconess Medical Center

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