title: Risk-standardized Acute Admission Rates Among Patients With Diabetes and Heart Failure as a Measure of Quality of Accountable Care Organizations: Rationale, Methods, and Early Results.
abstract: BACKGROUND
  Population-based measures of admissions among patients with chronic conditions are important quality indicators of Accountable Care Organizations (ACOs), yet there are challenges in developing measures that enable fair comparisons among providers.
  
  
  METHODS
  On the basis of consensus standards for outcome measure development and with expert and stakeholder input on methods decisions, we developed and tested 2 models of risk-standardized acute admission rates (RSAARs) for patients with diabetes and heart failure using 2010-2012 Medicare claims data. Model performance was assessed with deviance R; score reliability was tested with intraclass correlation coefficient. We estimated RSAARs for 114 Shared Savings Program ACOs in 2012 and we assigned ACOs to 3 performance categories: no different, worse than, and better than the national rate.
  
  
  RESULTS
  The diabetes and heart failure cohorts included 6.5 and 2.6 million Medicare Fee-For-Service beneficiaries aged 65 years and above, respectively. Risk-adjustment variables were age, comorbidities, and condition-specific severity variables, but not socioeconomic status or other contextual factors. We selected hierarchical negative binomial models with the outcome of acute, unplanned hospital admissions per 100 person-years. For the diabetes and heart failure measures, respectively, the models accounted for 22% and 12% of the deviance in outcomes and score reliability was 0.89 and 0.81. For the diabetes measure, 51 (44.7%) ACOs were no different, 45 (39.5%) were better, and 18 (15.8%) were worse than the national rate. The distribution of performance for the heart failure measure was 61 (53.5%), 37 (32.5%), and 16 (14.0%), respectively.
  
  
  CONCLUSIONS
  Measures of RSAARs for patients with diabetes and heart failure meet criteria for scientific soundness and reveal important variation in quality across ACOs.
authors.affiliation: *Section of Cardiovascular Medicine, Yale University School of Medicine †Center for Outcomes Research and Evaluation, Yale-New Haven Hospital Sections of ‡Endocrinology §General Internal Medicine Departments of ∥Internal Medicine, Robert Wood Johnson Foundation Clinical Scholars Program ¶Health Policy and Management #Pediatrics, Yale University School of Medicine, New Haven, CT.
authors.forename: Erica S
authors.initials: ES
authors.lastname: Spatz
authors.forename: Kasia J
authors.initials: KJ
authors.lastname: Lipska
authors.forename: Ying
authors.initials: Y
authors.lastname: Dai
authors.forename: Haikun
authors.initials: H
authors.lastname: Bao
authors.forename: Zhenqiu
authors.initials: Z
authors.lastname: Lin
authors.forename: Craig S
authors.initials: CS
authors.lastname: Parzynski
authors.forename: Faseeha K
authors.initials: FK
authors.lastname: Altaf
authors.forename: Erin K
authors.initials: EK
authors.lastname: Joyce
authors.forename: Julia A
authors.initials: JA
authors.lastname: Montague
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Ross
authors.forename: Susannah M
authors.initials: SM
authors.lastname: Bernheim
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Drye
mesh_terms: D060866:Accountable Care Organizations / Q000592:standards*; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000628:therapy*; D005260:Female; D006333:Heart Failure / Q000628:therapy*; D006801:Humans; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data; D010343:Patient Admission / Q000706:statistics & numerical data*; D011787:Quality of Health Care / Q000592:standards*; D044469:Racial Groups / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D020379:Risk Adjustment; D012720:Severity of Illness Index; D014481:United States