title: Is bigger always better? A nationwide study of hip fracture unit volume, 30-day mortality, quality of in-hospital care, and length of hospital stay.
abstract: BACKGROUND
  Higher patient volume has been linked with better clinical outcomes for a range of surgical procedures; however, little is known about the impact of volume on quality of care and clinical outcome among patients with hip fracture.
  
  
  OBJECTIVE
  To examine the association between hip fracture patient volume and 30-day mortality, quality of in-hospital care, time to surgery, and length of hospital stay, respectively.
  
  
  METHODS
  Population-based follow-up study.
  
  
  METHODS
  Using prospectively collected data from the Danish Multidisciplinary Hip Fracture Registry, we identified 12,065 patients 65 years and older who were admitted with a hip fracture between March 1, 2010 and November 30, 2011.
  
  
  METHODS
  Patient volume was divided into 3 groups; ≤ 151 hip fracture admissions per year, 152-350, and ≥ 351 admissions per year based on the distribution of the hospitals and to ensure a reasonable proportion of hospitals in each category. Data were analyzed using regression techniques while controlling for potential confounders.
  
  
  RESULTS
  Admission to high-volume units was associated with higher 30-day mortality [adjusted odds ratio (OR)=1.37 (95% confidence interval (CI), 1.14-1.64)] and a longer length of hospital stay (adjusted relative time=1.25 (95% CI, 1.02-1.52)]. Furthermore, patients had lower odds for being mobilized within 24 hours postoperatively and for receiving basic mobility assessment and a postdischarge rehabilitation program. Time to surgery was nonsignificantly increased [adjusted relative time=1.25 (95% CI, 0.99-1.58)].
  
  
  CONCLUSIONS
  Patients admitted to high-volume hip fracture units had higher mortality rates, received a lower quality of in-hospital care, and had longer length of hospital stay.
authors.affiliation: *Department of Orthopedic Surgery, Hospital Horsens, Sundvej, Horsens †Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark.
authors.forename: Pia K
authors.initials: PK
authors.lastname: Kristensen
authors.forename: Theis M
authors.initials: TM
authors.lastname: Thillemann
authors.forename: Søren P
authors.initials: SP
authors.lastname: Johnsen
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006620:Hip Fractures / Q000401:mortality* / Q000601:surgery; D061847:Hospitals, High-Volume / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D008137:Longitudinal Studies; D008297:Male; D016017:Odds Ratio; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D011787:Quality of Health Care / Q000706:statistics & numerical data*; D012737:Sex Factors; D013997:Time Factors