title: The Auckland Cataract Study: Assessing Preoperative Risk Stratification Systems for Phacoemulsification Surgery in a Teaching Hospital.
abstract: OBJECTIVE
  To evaluate 2 preoperative risk stratification systems for assessing the risk of complications in phacoemulsification cataract surgery, performed by residents, fellows, and attending physicians in a public teaching hospital.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  One observer assessed the clinical data of 500 consecutive cases, prior to phacoemulsification cataract surgery performed between April and June 2015 at Greenlane Clinical Centre, Auckland, New Zealand. Preoperatively 2 risk scores were calculated for each case using the Muhtaseb and Buckinghamshire risk stratification systems. Complications, intraoperative and postoperative, and visual outcomes were analyzed in relation to these risk scores.
  
  
  RESULTS
  Intraoperative complication rates increased with higher risk scores using the Muhtaseb or Buckinghamshire stratification system (P = .001 and P = .003, respectively, n = 500). The odds ratios for residents and fellows were not significantly different from attending physicians after case-mix adjustment according to risk scores (P > .05). Postoperative complication rates increased with higher Buckinghamshire risk scores but not with Muhtaseb scores (P = .014 and P = .094, respectively, n = 476). Postoperative corrected-distance visual acuity was poorer with higher risk scores (P < .001 for both, n = 476).
  
  
  CONCLUSIONS
  This study confirms that the risk of intraoperative complications increases with higher preoperative risk scores. Furthermore, higher risk scores correlate with poorer postoperative visual acuity and the Buckinghamshire risk score also correlates with postoperative complications. Therefore, preoperative assessment using such risk stratification systems could assist individual informed consent, preoperative surgical planning, safe allocation of cases to trainees, and more meaningful analyses of outcomes for individual surgeons and institutions.
authors.affiliation: Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Science, University of Auckland, Auckland, New Zealand; Department of Ophthalmology, Greenlane Clinical Centre, Greenlane Hospital, Auckland District Health Board, Auckland, New Zealand.
authors.forename: Bia Z
authors.initials: BZ
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Science, University of Auckland, Auckland, New Zealand; Department of Ophthalmology, Greenlane Clinical Centre, Greenlane Hospital, Auckland District Health Board, Auckland, New Zealand.
authors.forename: Dipika V
authors.initials: DV
authors.lastname: Patel
authors.affiliation: Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Science, University of Auckland, Auckland, New Zealand.
authors.forename: Trevor
authors.initials: T
authors.lastname: Sherwin
authors.affiliation: Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Science, University of Auckland, Auckland, New Zealand; Department of Ophthalmology, Greenlane Clinical Centre, Greenlane Hospital, Auckland District Health Board, Auckland, New Zealand. Electronic address: c.mcghee@auckland.ac.nz.
authors.forename: Charles N J
authors.initials: CN
authors.lastname: McGhee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002386:Cataract / Q000453:epidemiology*; D002983:Clinical Competence; D004503:Education, Medical, Graduate / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006784:Hospitals, Teaching; D006801:Humans; D007396:Internship and Residency; D007431:Intraoperative Complications / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009520:New Zealand / Q000453:epidemiology; D009885:Ophthalmology / Q000193:education*; D018918:Phacoemulsification / Q000009:adverse effects* / Q000193:education; D057234:Preoperative Period; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D055815:Young Adult