title: Use of a novel statistical technique to examine the delivery of breast cancer follow-up care by different types of oncology providers.
abstract: OBJECTIVE
  Frequent follow-up is recommended for the more than 3 million breast cancer survivors living in the USA. Given the multidisciplinary nature of breast cancer treatment, follow-up may be provided by medical oncologists, radiation oncologists, surgeons and primary care providers. This creates the potential for significant redundancy as well as gaps in care. The objective was to examine patterns of breast cancer follow-up provided by different types of oncologists and develop a statistical means of quantifying visit distribution over time.
  
  
  METHODS
  We identified stage I-III breast cancer patients who underwent breast conservation from 2000 to 2006 (n = 12 139) within the SEER-Medicare linked database. Provider type was defined using Medicare specialty provider codes and AMA Masterfile. The coefficient of variation (CV) for time between oncologist follow-up visits was calculated. Ordinal logistic regression assessed factors associated with CV.
  
  
  RESULTS
  Substantial variation in CV was observed. Sixty-seven per cent of patients with low CV (high visit regularity) received follow-up from a single oncologist type, versus 8% with high CV (low visit regularity). The number of oncologist types participating in follow-up had the greatest association with high CV (odds ratio 7.4 [6.7-8.3] and 15.4 [13.6-17.6] for two and three oncologist types).
  
  
  CONCLUSIONS
  Using a novel means of quantifying follow-up visit regularity, we determined that breast cancer patients with dispersed follow-up with more than one oncologist have more disordered care. The CV could be used in electronic medical records to identify cancer survivors with more disordered.
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, UW Madison School of Medicine and Public Health, Madison, WI, USA. neuman@surgery.wisc.edu.|University of Wisconsin Carbone Cancer Center, UW Madison School of Medicine and Public Health, Madison, WI, USA. neuman@surgery.wisc.edu.
authors.forename: Heather B
authors.initials: HB
authors.lastname: Neuman
authors.affiliation: Department of Biostatistics and Medical Informatics, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Rathouz
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Winslow
authors.affiliation: University of Wisconsin Carbone Cancer Center, UW Madison School of Medicine and Public Health, Madison, WI, USA.|Department of Medicine, Division of Gastroenterology and Hepatology, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Weiss
authors.affiliation: University of Wisconsin Carbone Cancer Center, UW Madison School of Medicine and Public Health, Madison, WI, USA.|Department of Medicine, Division of Hematology and Oncology, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Noelle K
authors.initials: NK
authors.lastname: LoConte
authors.affiliation: Center for Clinical and Translational Science, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Chee Paul
authors.initials: CP
authors.lastname: Lin
authors.affiliation: Department of Biostatistics and Medical Informatics, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Mike
authors.initials: M
authors.lastname: Wurm
authors.affiliation: University of Wisconsin Carbone Cancer Center, UW Madison School of Medicine and Public Health, Madison, WI, USA.|Department of Population Health Sciences, UW Madison School of Medicine and Public Health, Madison, WI, USA.|Department of Family Medicine, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Maureen A
authors.initials: MA
authors.lastname: Smith
authors.affiliation: Center for Outcomes and Policy Research, Dana-Farber Cancer Institute, Boston, MA, USA.
authors.forename: Deborah
authors.initials: D
authors.lastname: Schrag
authors.affiliation: Wisconsin Surgical Outcomes Research Program, Department of Surgery, UW Madison School of Medicine and Public Health, Madison, WI, USA.|University of Wisconsin Carbone Cancer Center, UW Madison School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Caprice C
authors.initials: CC
authors.lastname: Greenberg
mesh_terms: D000359:Aftercare / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000601:surgery*; D005260:Female; D006282:Health Personnel; D006801:Humans; D015412:Mastectomy, Segmental; D008495:Medical Oncology; D017741:Survivors
keywords: breast cancer; care coordination; coefficient of variation; health care delivery; surveillance; survivorship