title: An index for measuring overuse of health care resources with Medicare claims.
abstract: BACKGROUND
  Overuse can be defined as use of a service when the risk of harm exceeds its likely benefit. Yet, there has been little work with composite measures of overuse.
  
  
  OBJECTIVE
  Our goal was to create a composite measure of overuse with claims data.
  
  
  METHODS
  Observational study using 5% of Medicare claims from 2008.
  
  
  METHODS
  All inpatient and outpatient settings of care, excluding nursing homes.
  
  
  METHODS
  Older Americans receiving health care services in hospitals or outpatient settings.
  
  
  METHODS
  We applied algorithms to identify specific cases of overuse across 20 previously identified procedures and used multilevel modeling techniques to examine variation in overuse across all procedures. Included in the model were patient-level factors and both procedure and regional fixed effects for the 306 hospital referral regions (HRR). These estimated regional fixed effects, representing the systematic, region variation in overuse across all measures, was then normalized compared with the overall average to generate a Z score for each HRR. The resulting "Overuse Index" was then compared with total costs, 30-day postdischarge mortality, and total mortality at the HRR level, graphically, and associations were tested using Spearman ρ.
  
  
  RESULTS
  The Overuse Index varied markedly across regions, but 23 were higher than the average (P<0.05). The Index was positively associated with total costs (ρ=0.28, P<0.0001). It was positively correlated with 30-day postdischarge mortality (ρ=0.18 P≤0.005), and neither positively or negatively correlated with total mortality.
  
  
  CONCLUSIONS
  This study confirms previous research hypothesizing that systematic regional variation in overuse exists and is measurable. Addition research is needed to validate index and to test its predictive and concurrent validity in panel data.
authors.affiliation: *Johns Hopkins School of Medicine †Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD.
authors.forename: Jodi B
authors.initials: JB
authors.lastname: Segal
authors.forename: Najlla
authors.initials: N
authors.lastname: Nassery
authors.forename: Hsien-Yen
authors.initials: HY
authors.lastname: Chang
authors.forename: Eva
authors.initials: E
authors.lastname: Chang
authors.forename: Kitty
authors.initials: K
authors.lastname: Chan
authors.forename: John F P
authors.initials: JF
authors.lastname: Bridges
mesh_terms: D000368:Aged; D003362:Cost-Benefit Analysis; D005260:Female; D005102:Health Expenditures / Q000706:statistics & numerical data*; D006300:Health Services Misuse / Q000191:economics / Q000706:statistics & numerical data*; D006304:Health Status; D006801:Humans; D007344:Insurance Claim Reporting / Q000191:economics / Q000706:statistics & numerical data*; D008297:Male; D006278:Medicare / Q000191:economics / Q000706:statistics & numerical data*; D008875:Middle Aged; D057240:Patient Preference / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology