Refractive ocular conditions and reasons for spectacles renewal in a resource-limited economy

<p>Abstract</p> <p>Background</p> <p>Although a leading cause of visual impairment and a treatable cause of blindness globally, the pattern of refractive errors in many populations is unknown. This study determined the pattern of refractive ocular conditions, reasons for spectacles renewal and the effect of correction on refractive errors in a resource-limited community.</p> <p>Methods</p> <p>A retrospective review of case records of 1,413 consecutive patients seen in a private optometry practice, Nigeria between January 2006 and July 2007.</p> <p>Results</p> <p>A total number of 1,216 (86.1%) patients comprising of (486, 40%) males and (730, 60%) females with a mean age of 41.02 years SD 14.19 were analyzed. The age distribution peaked at peri-adolescent and the middle age years. The main ocular complaints were spectacles loss and discomfort (412, 33.9%), blurred near vision (399, 32.8%) and asthenopia (255, 20.9%). The mean duration of ocular symptoms before consultation was 2.05 years SD 1.92. The most common refractive errors include presbyopia (431, 35.3%), hyperopic astigmatism (240, 19.7%) and presbyopia with hyperopia (276, 22.7%). Only (59, 4.9%) had myopia. Following correction, there were reductions in magnitudes of the blind (VA<3/60) and visually impaired (VA<6/18-3/60) patients by (18, 58.1%) and (89, 81.7%) respectively. The main reasons for renewal of spectacles were broken lenses/frame/scratched lenses/lenses' falling off (47, 63.4%).</p> <p>Conclusions</p> <p>Adequate correction of refractive errors reduces visual impairment and avoidable blindness and to achieve optimal control of refractive errors in the community, services should be targeted at individuals in the peri-adolescent and the middle age years.</p

Impact pathways of small-scale energy projects in the global south : findings from a systematic evaluation

Access to clean and affordable modern energy services has been widely recognised as a significant factor for enabling social and economic development. Stand-alone systems and mini-grids are presumed to play an important role in the provision of sustainable energy to those people who currently lack access. Accordingly, an increasing number of small-scale energy projects are being implemented in developing countries and emerging economies. However, despite the large number of energy development projects, only limited evidence exists about the actual contribution they make to sustainable development. This paper addresses this research gap by providing a systematic assessment of three selected impact pathways based on the evaluation of over 30 small-scale sustainable energy projects. Applying a theory-based evaluation approach in the form of a contribution analysis, the aim of this research is to better understand if and how these types of technical interventions can create development outcomes and impacts. The results show that technological issues are often not the most decisive factor in achieving development effects, but that embedding the technology in a set of actions that address social, cultural, economic and environmental aspects is essential