title: Retinopathy of prematurity screening criteria and workload implications at Tygerberg Children's Hospital, South Africa: A cross-sectional study.
abstract: BACKGROUND
  Screening guidelines for retinopathy of prematurity (ROP) used in high-income countries are not appropriate for middle- income countries, and screening requirements may vary even between units within one city.
  
  
  OBJECTIVE
  To determine optimal ROP screening criteria, and its workload implications, for Tygerberg Children's Hospital (TCH), Cape Town, South Africa.
  
  
  METHODS
  This cross-sectional study included premature infants screened for ROP at TCH from 1 January 2009 to 31 December 2014. Logistic regression analysis for prediction and classification was performed. Predictors were birth weight (BW) and gestational age (GA). Endpoints were clinically significant ROP (CSROP) and type 1 ROP (T1ROP).
  
  
  RESULTS
  Of 1 104 eligible infants, 33.4% had ROP (CSROP 9.1%, T1ROP 2.5%). All T1ROP infants received laser therapy. The number of screening examinations was inversely correlated with GA and BW. The number needed to screen to identify one infant requiring treatment was 41 (entailing 83 examinations, 4 screening hours, one technician and three doctors). Screening infants with a GA of ≤28 weeks or a BW of &lt;1 000 g would have detected all infants with T1ROP but missed two outliers with CSROP. These outliers would only have been detected with a GA of ≤32 weeks or a BW &lt;1 500 g.
  
  
  CONCLUSIONS
  Detection of infants with T1ROP is resource intensive. Larger infants require screening to include a few outliers, but they require fewer examinations than smaller infants. Making local screening criteria narrower on the basis of a limited evidence base may be dangerous. Risk factors for CSROP in larger infants need to be researched.
authors.affiliation: Division of Clinical Pharmacology, Department of Medicine, Tygerberg Hospital and Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, Cape Town; Division of Epidemiology and Biostatistics, School of Public Health and Family Medicine, Faculty of Health Sciences, University of Cape Town; Previously affiliated to the Division of Ophthalmology, Department of Surgery, Tygerberg Hospital and Stellenbosch University, Tygerberg, Cape Town, South Africa. evkift@sun.ac.za.
authors.forename: Elsime
authors.initials: E
authors.lastname: Visser Kift
authors.forename: Nicola
authors.initials: N
authors.lastname: Freeman
authors.forename: Colin
authors.initials: C
authors.lastname: Cook
authors.forename: Landon
authors.initials: L
authors.lastname: Myer