title: Unrecognized and unregistered blindness in people 70 or older in Jing'an district, Shanghai, China.
abstract: OBJECTIVE
  To evaluate the efficacy of a registration system for the blind people and to monitor the blindness due to uncorrected refractive error and cataract in Jing'an district, Shanghai, China.
  
  
  METHODS
  Five hundred and ten blind people, based on visual acuity screening in a population aged 70 or older were enrolled into the study. Four hundred and forty subjects were interviewed. The following data were collected on each patient: demographic data, number of hospital visits for eye related problems, distance visual acuity, visual fields, ophthalmic diagnoses, education and registration status. If the eligible subject was not registered as blind, the reason for non-registration was recorded.
  
  
  RESULTS
  Ten point nine one percent blindness was due to cataract, 27.5% due to uncorrected refractive error, and only 61.59% met the eligible blindness criteria (uncorrected refractive error and cataract are not considered as eligible blindness). The first four leading causes of eligible blindness were age related macular degeneration (25.09%), myopic macular degeneration (21.40%), glaucoma (18.82%) and corneal disease (8.12%). Only 68.27% eligible blind people were registered. The patients with macular degeneration and glaucoma tended not to register. Blind people with an above primary school education were 2.59 times more likely to be registered than those who were illiterate or had only a primary school education (OR=2.59, 95%CI: 1.49-4.48, P<0.01). Patients who had 4 or more visits to the hospital requesting eye care services in a year were 2.2 times more likely to be registered than those with less than 4 visits to the hospital (OR=2.54, 95%CI: 1.47-4.38, P<0.001). The first two leading reasons of misregistration were unknowing the registration system (48%) and unwilling to register (21%).
  
  
  CONCLUSIONS
  Under-registration of the eligible blind people exists in the registry system. Education and the number of hospital visits for eye care services were factors associated with registration levels. Uncorrected refractive error and cataract are important causes of blindness.
authors.affiliation: Department of Ophthalmology, Jing'an District Centre Hospital of Shanghai, Eye Diseases Prevention and Treatment Institute of Jing'an District, Shanghai 200040, China.
authors.forename: Liang-Cheng
authors.initials: LC
authors.lastname: Wu
authors.forename: Xing-Huai
authors.initials: XH
authors.lastname: Sun
authors.forename: Xing-Tao
authors.initials: XT
authors.lastname: Zhou
authors.forename: Cheng-Hai
authors.initials: CH
authors.lastname: Wen
keywords: blindness; causes; unrecognized