Correction of refractive error and presbyopia in Timor-Leste

Abstract

Aim: To investigate the aspects of spectacle correction of vision-impairing refractive error and presbyopia in those aged >40 years in Timor-Leste. Method: A population-based cross-sectional survey with cluster random sampling was used to select 50 clusters of 30 people. Those who had uncorrected or undercorrected refractive error (presenting acuity worse than 6/18, but at least 6/18 with pinhole), uncorrected or undercorrected presbyopia (near vision worse than N8), and/or who were using or had used spectacles were identified. Dispensing history, willingness to wear and willingness to pay for spectacles were elicited.

Age-specific changes in the prevalence and management of optically correctable visual impairment between 1988 and 2000: the Ponza Eye Study

“…From a practical point of view, the OCVI rate corresponds to the variable referred to as 'total need for spectacles' in previous studies. 11,13,15,16 It is important to note, however, that the subjects analysed in the latter studies (and in our study as well) do not represent all those in the study population who need or might benefit from refractive correction. Notable exclusions include subjects with impaired near vision, those with milder distance impairments that fail to satisfy the preestablished criterion for impairment, and those whose VI might be improved with corrective lenses without achieving the normal VA cutoff established by the study protocol.…”

“…27 Slightly different definitions have been used in other studies of this type, 11,13,15,16 and to facilitate comparisons, we also re-elaborated our data using these cutoffs. As in previous studies, 11,13,15,16 we classified subjects based exclusively on the VA of the better eye.…”

“…These groups correspond to the groups with met and unmet needs for spectacles in the studies cited above. 11,13,15,16 Almost half the participants examined in 2000 were members of the original 1988 cohort. To avoid comparison of partially dependant samples, we divided both populations into non-conventional age groups (40-51, 52-63, 64-75, and 76-87 years) based on intervals of 12 years, ie the interval between the two studies, and statistical analyses were carried out separately for each age group.…”

“…Spectacle utilization rates are an important indicator of the availability of refractive services in a population and of subjects' compliance with prescriptions, but this parameter has been investigated in relatively few studies. 11,13,15,16 In addition, there is no information on how these rates are changing, which is an important reflection of the success or failure of strategies for eliminating refractive errors. The Blue Mountains Eye Study is the only study that has assessed temporal changes in the rates of correctable VI in an industrialized Western population.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] The World Health Organization (WHO) estimated that in 2004, there were 153 million people in the world who were visually impaired by uncorrected refractive errors. 19 For this reason, refractive errors are among the conditions targeted by Vision 2020: The Right to Sight, a global initiative organized by the WHO and the International Agency for the Prevention of Blindness with the aim of eliminating avoidable forms of blindness.…”