Original ArticleRapid Assessment of Avoidable Blindness in Nakuru District, Kenya
Section snippets
Sample Selection
The expected prevalence of blindness in ≥50-year-olds was estimated conservatively at 4.5%.1, 10, 11 Allowing for a required confidence of 95%, precision of 20% (i.e., worst acceptable result of 3.6%), population size of 88 700 people 50 or older in Nakuru,12 expected design effect of 1.7 for clusters of 50 based on data from the RACSS,2 and 10% nonresponse, the required sample size was estimated to be 3725 subjects (Epi Info 6.04, Centers for Disease Control and Prevention, Atlanta, GA). In
Results
The study population consisted of 3784 people. Two hundred twenty-two (5.9%) were not available, and 59 (1.6%) refused to be examined, so 3503 were included in the survey (92.6%). There was no difference in mean ages of those who were unavailable (61.3 years), those who refused (61.0), and those who were included (62.3), but those who refused were more likely to be female (66.1% of refusers vs. 46.9% of those unavailable and 52.4% of those examined). Of the 222 who were not available, 2 were
Avoidable Blindness
Vision 2020: The Right to Sight was launched in 1999 with the goal of eliminating avoidable blindness by 2020. The concept of avoidable blindness combines those diseases that are either easily preventable or treatable. The RACSS has been used and reported by several countries.2, 3, 4, 5, 6, 7, 8 The RACSS methodology has been adapted and used for the first time in this survey to assess the prevalence of avoidable blindness, not only cataract, using new data entry and analysis tools.
Experience with Rapid Assessment of Avoidable Blindness and Sampling
Compact
References (25)
- et al.
Cataract surgical coverage and outcome of cataract surgery in a rural district in Malawi
Can J Ophthalmol
(2004) - et al.
Global data on visual impairment in the year 2002
Bull World Health Organ
(2004) - et al.
Rapid assessment of prevalence of cataract blindness at district level
Int J Epidemiol
(1997) - et al.
A proposed rapid methodology to assess the prevalence and causes of blindness and visual impairment
Ophthalmic Epidemiol
(2006) - et al.
Cataract blindness in Chakwal District, Pakistan: results of a survey
Ophthalmic Epidemiol
(2003) - et al.
Cataract blindness in Turkmenistan: results of a national survey
Br J Ophthalmol
(2002) - et al.
Cataract blindness in Paraguay—results of a national survey
Ophthalmic Epidemiol
(2003) - et al.
Rapid assessment of cataract surgical services in age group 50 years and above in Lower Dir District, Malakand, Pakistan
J Coll Physicians Surg Pak
(2005) - et al.
Ceguera por catarata en personas mayores de 50 años en una zona semirrural del norte del Peru
Rev Panam Salud Publica
(2005)
A prevalence survey of ophthalmic diseases among the Turkana tribe in north-west Kenya
Br J Ophthalmol
Blindness and eye disease in Kenya: ocular status survey results from the Kenya Rural Blindness Prevention Project
Br J Ophthalmol
Cited by (0)
Manuscript no. 2005-1211.
Supported by grants from the Christian Blind Mission, Bensheim, Germany; Sight Savers International, Haywards Heath, United Kingdom; and ORBIS International, London, United Kingdom.