title: The Evonik-Mainz Eye Care-Study (EMECS): Development of an Expert System for Glaucoma Risk Detection in a Working Population.
abstract: OBJECTIVE
  To develop an expert system for glaucoma screening in a working population based on a human expert procedure using images of optic nerve head (ONH), visual field (frequency doubling technology, FDT) and intraocular pressure (IOP).
  
  
  METHODS
  4167 of 13037 (32%) employees between 40 and 65 years of Evonik Industries were screened. An experienced glaucoma expert (JW) assessed papilla parameters and evaluated all individual screening results. His classification into "no glaucoma", "possible glaucoma" and "probable glaucoma" was defined as "gold standard". A screening model was developed which was tested versus the gold-standard. This model took into account the assessment of the ONH. Values and relationships of CDR and IOP and the FDT were considered additionally and a glaucoma score was generated. The structure of the screening model was specified a priori whereas values of the parameters were chosen post-hoc to optimize sensitivity and specificity of the algorithm. Simple screening models based on IOP and / or FDT were investigated for comparison.
  
  
  RESULTS
  111 persons (2.66%) were classified as glaucoma suspects, thereof 13 (0.31%) as probable and 98 (2.35%) as possible glaucoma suspects by the expert. Re-evaluation by the screening model revealed a sensitivity of 83.8% and a specificity of 99.6% for all glaucoma suspects. The positive predictive value of the model was 80.2%, the negative predictive value 99.6%. Simple screening models showed insufficient diagnostic accuracy.
  
  
  CONCLUSIONS
  Adjustment of ONH and symmetry parameters with respect to excavation and IOP in an expert system produced sufficiently satisfying diagnostic accuracy. This screening model seems to be applicable in such a working population with relatively low age and low glaucoma prevalence. Different experts should validate the model in different populations.
authors.affiliation: Department of Ophthalmology, Helios Dr. Horst Schmidt Kliniken, Wiesbaden, Germany.|Department of Ophthalmology, University Medical Center, Johannes-Gutenberg-University, Mainz, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Wahl
authors.affiliation: Department of Ophthalmology, University Medical Center, Johannes-Gutenberg-University, Mainz, Germany.|Department of Ophthalmology, Diakonissen Krankenhaus, Karlsruhe-Rüppurr, Germany.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Barleon
authors.affiliation: Institute for Occupational Medicine of Cologne University, Köln, Germany.|Institute for Occupational Epidemiology and Risk Assessment of Evonik Industries, Essen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Morfeld
authors.affiliation: Bundeswehrzentralkrankenhaus Koblenz, Abteilung X (Anästhesie, Intensivmedizin, Notfallmedizin, Schmerz), Koblenz, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lichtmeß
authors.affiliation: Occupational Health, Evonik Industries, Hanau, Germany.
authors.forename: Sibylle
authors.initials: S
authors.lastname: Haas-Brähler
authors.affiliation: Department of Ophthalmology, University Medical Center, Johannes-Gutenberg-University, Mainz, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Pfeiffer
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D017281:Cost of Illness; D003937:Diagnosis, Differential; D005260:Female; D005901:Glaucoma / Q000175:diagnosis* / Q000191:economics / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D009898:Optic Disk / Q000000981:diagnostic imaging; D015995:Prevalence; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014065:Tonometry, Ocular; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology