title: [Comparison of visual impairment caused by trachoma in China between 1978 and 2006].
abstract: OBJECTIVE
  To understand the distribution of visual impairment caused by trachoma in China and provide evidences for evaluation of eliminating blinding trachoma in China in the mission of Vision 2020.
  
  
  METHODS
  Sampling study. The results from the first year 1987 and second (year 2006) national sampling surveys of disabled persons were analyzed. Chi-square test was performed using SAS 9.30 to analyze the rates of visual impairment caused by trachoma in different groups. Unifactor and multifactor analyses were applied to analyze the relevance between visual impairment caused by trachoma and risk factors, including gender and age.
  
  
  RESULTS
  The rate of visual impairment caused by trachoma was 102.01 persons/100 000 in 1987 and 17.62 persons/100 000 in 2006. The percentage of trachoma in all kinds of visual impairment was 14.25% in 1987 and 1.87% in 2006, and the difference was significant (F = 1 382.6, P < 0.01). Spatial aggregation was obvious in visual impairment caused by trachoma. H-aggregation areas included Hubei, Sichuan, Anhui, Shannxi, Guizhou, Hunan provinces and Chongqing Municipality. Survival time without trachoma between 1987 and 2006 was significantly different (F = 2 745.9, P < 0.01). The rate and risk of visual impairment caused by trachoma increased with age. Except the group of > 85 years, the rate of visual impairment caused by trachoma in all age groups in 1987 was significantly higher than that in 2006. The risk of visual impairment caused by trachoma in 1987 was 5.8 times that in 2006. If the other risk factors were not involved, the risk in 1987 was 8.75 times that in 2006. The risk in females was twice that in males.
  
  
  CONCLUSIONS
  Both, the rate and risk of visual impairment caused by trachoma were significantly reduced in China. Impressive progresses were achieved in trachoma prevention and control.
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China.
authors.forename: Ailian
authors.initials: A
authors.lastname: Hu
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China.
authors.forename: Xiaogu
authors.initials: X
authors.lastname: Cai
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China.
authors.forename: Liya
authors.initials: L
authors.lastname: Qiao
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China.
authors.forename: Baochen
authors.initials: B
authors.lastname: Sun
authors.affiliation: Beijing Institute of Ophthalmology, BeijingTongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Vision Science Key Lab., Beijing 100730, China; Email: wningli@vip.163.com.
authors.forename: Ningli
authors.initials: N
authors.lastname: Wang
mesh_terms: D000367:Age Factors; D016009:Chi-Square Distribution; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D014141:Trachoma / Q000150:complications*; D014786:Vision Disorders / Q000453:epidemiology / Q000209:etiology*