title: Cycloplegic autorefraction versus subjective refraction: the Tehran Eye Study.
abstract: OBJECTIVE
  To compare cycloplegic autorefraction with non-cycloplegic subjective refraction across all age and refractive error groups.
  
  
  METHODS
  In a cross-sectional study with random stratified cluster sampling, 160 clusters were chosen from various districts proportionate to the population of each district in Tehran. Following retinoscopy and autorefraction with the 0.25 D bracketing (Topcon KR-8000, Topcon, Tokyo, Japan), all participants had a subjective refraction. Then all participants underwent cycloplegic autorefraction.
  
  
  RESULTS
  The final analysis was performed on 3482 participants with a mean age of 31.7 years (range 5-92 years). Based on cycloplegic and subjective refraction, mean spherical equivalent (SE) was +0.31±1.80 and -0.32±1.61 D, respectively (p<0.001). The 95% limits of agreement (LoA) between these two types of refraction were from -0.40 to 1.70 D. The largest difference between these two types of refraction was seen in the age group of 5-10 years (1.11±0.60 D), and the smallest difference was in the age group of >70 years (0.34±0.45 D). The 95% LoA was -0.52 to 0.89 D in patients with myopia and -0.12 to 2.04 D in patients with hyperopia. We found that female gender (coefficients=0.048), older age (coefficients=-0.247), higher education (coefficients=-0.043) and cycloplegic SE (coefficients=-0.472) significantly correlated with lower intermethod differences.
  
  
  CONCLUSIONS
  The cycloplegic refraction is more sensitive than the subjective one to measure refractive error at all age groups especially in children and young adults. The cyclorefraction technique is highly recommended to exactly measure the refractive error in momentous conditions such as refractive surgery, epidemiological researches and amblyopia therapy, especially in hypermetropic eyes and paediatric cases.
authors.affiliation: Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Hashemi
authors.affiliation: Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Khabazkhoob
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Asharlous
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Soroush
authors.affiliation: Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: AbbasAli
authors.initials: A
authors.lastname: Yekta
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.
authors.forename: Nooshin
authors.initials: N
authors.lastname: Dadbin
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Akbar
authors.initials: A
authors.lastname: Fotouhi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009184:Mydriatics / Q000494:pharmacology*; D015995:Prevalence; D012029:Refraction, Ocular / Q000187:drug effects* / Q000502:physiology; D012030:Refractive Errors / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D014787:Vision Tests; D055815:Young Adult
chemical_list: D009184:Mydriatics
keywords: Optics and Refraction