title: Adherence to quality indicators and survival in patients with breast cancer.
abstract: BACKGROUND
  International initiatives increasingly advocate physician adherence to clinical protocols that have been shown to improve outcomes, yet the process-outcome relationship for adhering to breast cancer care protocol is unknown.
  
  
  OBJECTIVE
  This study explores whether 100% adherence to a set of quality indicators applied to individuals with breast cancer is associated with better survival.
  
  
  METHODS
  Ten quality indicators (4 diagnosis-related and 6 treatment-related indicators) were used to measure the quality of care in 1378 breast cancer patients treated from 1995 to 2001. Adherence to each indicator was based on the number of procedures performed divided by the number of patients eligible for that procedure. The main analysis of adherence was dichotomous (ie, 100% adherence vs. <100% adherence).
  
  
  METHODS
  The outcome measures studied were 5-year overall survival and progression-free survival, calculated using the Kaplan-Meier method. The Cox's proportional hazard regression model was used for univariate and multivariate analyses.
  
  
  RESULTS
  Most patients received care that demonstrated good adherence to the quality indicators. Multivariate analysis revealed that 100% adherence to entire set of quality indicators was significantly associated with better overall survival [hazard ratio (HR): 0.46; 95% confidence interval (CI): 0.33-0.63] and progression-free survival (HR 0.51; 95% CI, 0.39-0.67). One hundred percent adherence to treatment indicators alone was also associated with statistically significant improvements in overall and progression-free survivals.
  
  
  CONCLUSIONS
  Our study strongly supports that 100% adherence to evidence supported quality-of-care indicators is associated with better survival rates for breast cancer patients and should be a priority for practitioners.
authors.affiliation: Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan.
authors.forename: Skye H
authors.initials: SH
authors.lastname: Cheng
authors.forename: C Jason
authors.initials: CJ
authors.lastname: Wang
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Lin
authors.forename: Cheng-Fang
authors.initials: CF
authors.lastname: Horng
authors.forename: Mei-Chun
authors.initials: MC
authors.lastname: Lu
authors.forename: Steven M
authors.initials: SM
authors.lastname: Asch
authors.forename: Lee H
authors.initials: LH
authors.lastname: Hilborne
authors.forename: Mei-Ching
authors.initials: MC
authors.lastname: Liu
authors.forename: Chii-Ming
authors.initials: CM
authors.lastname: Chen
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Huang
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D019983:Guideline Adherence / Q000592:standards*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality; D009367:Neoplasm Staging; D010043:Outcome and Process Assessment, Health Care; D016016:Proportional Hazards Models; D019984:Quality Indicators, Health Care / Q000592:standards*; D016019:Survival Analysis; D013624:Taiwan