title: Association of hospital and surgeon volume of total hip replacement with functional status and satisfaction three years following surgery.
abstract: OBJECTIVE
  To evaluate whether hospital volume and surgeon volume of total hip replacements (THRs) are associated with patient-reported functional status and satisfaction with surgery 3 years postoperatively.
  
  
  METHODS
  We performed a population-based cohort study of a stratified random sample of Medicare beneficiaries who underwent elective primary or revision THR in Ohio, Pennsylvania, or Colorado in 1995. The primary outcomes were the self-reported Harris hip score and a validated scale measuring satisfaction with the results of surgery. Both outcomes were assessed 3 years postoperatively. Hospital volume was defined as the aggregate number of elective primary and revision THRs performed on Medicare beneficiaries in the hospital in 1995. High-volume hospitals were defined as those in which >100 such procedures are performed annually, and low-volume centers were defined as those in which </=12 procedures (primary THR cohort) or </=30 procedures (revision cohort) are performed annually.
  
  
  RESULTS
  In unadjusted analyses, patients who underwent surgery in low-volume centers had worse functional status 3 years following primary and revision THR compared with patients whose surgery was performed in higher-volume centers. Patients whose revision THR was performed by a low-volume surgeon also had worse function. After adjustment for sociodemographic and clinical variables, however, the association between higher hospital volume and better functional status following primary THR was weak and statistically nonsignificant, and no statistically significant or clinically important associations between hospital or surgeon volume and functional status following revision THR was observed. Patients who underwent elective primary THR in low-volume centers were more likely to be dissatisfied with the results of surgery compared with patients whose surgeries were performed in high-volume centers. Similarly, patients whose surgeons performed </=12 procedures per year were more likely to be dissatisfied with the results of revision THR than were patients whose surgeons performed >12 procedures per year.
  
  
  CONCLUSIONS
  Hospital volume and surgeon volume have little effect on 3-year functional outcome following THR, after adjusting for patient sociodemographic and select clinical characteristics. However, satisfaction with primary THR is greater among patients who underwent surgery in high-volume centers, and satisfaction with revisions is greater among patients whose operations were performed by higher-volume surgeons. Referring clinicians should incorporate these findings into their discussion of referral choices with patients considering THR. Conclusions regarding the effect of volume on longevity of the implants must await longer-term followup studies. Finally, further research is warranted to better understand the association between hospital and surgeon procedure volume and patient satisfaction with surgery.
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, 75 Francis Street, B-3, Boston, MA 02115, USA. jnkatz@partners.org
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Katz
authors.forename: Charlotte B
authors.initials: CB
authors.lastname: Phillips
authors.forename: John A
authors.initials: JA
authors.lastname: Baron
authors.forename: Anne H
authors.initials: AH
authors.lastname: Fossel
authors.forename: Nizar N
authors.initials: NN
authors.lastname: Mahomed
authors.forename: Jane
authors.initials: J
authors.lastname: Barrett
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Lingard
authors.forename: William H
authors.initials: WH
authors.lastname: Harris
authors.forename: Robert
authors.initials: R
authors.lastname: Poss
authors.forename: Robert A
authors.initials: RA
authors.lastname: Lew
authors.forename: Edward
authors.initials: E
authors.lastname: Guadagnoli
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Wright
authors.forename: Elena
authors.initials: E
authors.lastname: Losina
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000191:economics / Q000592:standards* / Q000706:statistics & numerical data*; D015331:Cohort Studies; D005260:Female; D013502:General Surgery / Q000706:statistics & numerical data; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data; D008297:Male; D015999:Multivariate Analysis; D010043:Outcome and Process Assessment, Health Care; D017060:Patient Satisfaction; D020127:Recovery of Function; D012923:Social Class