AIM: To document the detection of significant ocular pathology by a vision-centre technician in an emerging economy World Health Organization recommended eye care delivery setting, and determine whether a frequency-doubling perimeter (FDT) improves that performance. MATERIAL AND METHODS: Consecutive patients above the age of 12 years attending a vision centre were included. A vision technician (VT) determined visual acuity and performed a slit-lamp examination, applanation tonometry and undilated fundus examination followed by a 20-1 FDT screening test. VT and FDT findings were compared with the gold standard of masked comprehensive examination by an ophthalmologist. Sensitivity, specificity and predictive values were calculated. RESULTS: 1764 of 1829 patients fulfilling the inclusion and exclusion criteria were analysed. The VT had a sensitivity and specificity of 68% (95% CI 63.1% to 72.7%) and 90% (95% CI 88.35% to 91.5%) for detection of significant ocular disease; corresponding values for FDT alone were 87.8% (95% CI 84% to 90.8%) and 79% (95% CI 76.8% to 81%). 71 of the 115 patients having significant ocular pathology missed by the VT were detected by FDT. A positive finding by the VT and/or positive FDT had a positive predictive value of 47%. CONCLUSIONS: An examination by a VT within the accepted World Health Organization model may usefully leverage limited ophthalmological capacity in emerging economies. Adjunctive FDT testing may further improve VT referral efficiency.
AIM: To document the detection of significant ocular pathology by a vision-centre technician in an emerging economy World Health Organization recommended eye care delivery setting, and determine whether a frequency-doubling perimeter (FDT) improves that performance. MATERIAL AND METHODS: Consecutive patients above the age of 12 years attending a vision centre were included. A vision technician (VT) determined visual acuity and performed a slit-lamp examination, applanation tonometry and undilated fundus examination followed by a 20-1 FDT screening test. VT and FDT findings were compared with the gold standard of masked comprehensive examination by an ophthalmologist. Sensitivity, specificity and predictive values were calculated. RESULTS: 1764 of 1829 patients fulfilling the inclusion and exclusion criteria were analysed. The VT had a sensitivity and specificity of 68% (95% CI 63.1% to 72.7%) and 90% (95% CI 88.35% to 91.5%) for detection of significant ocular disease; corresponding values for FDT alone were 87.8% (95% CI 84% to 90.8%) and 79% (95% CI 76.8% to 81%). 71 of the 115 patients having significant ocular pathology missed by the VT were detected by FDT. A positive finding by the VT and/or positive FDT had a positive predictive value of 47%. CONCLUSIONS: An examination by a VT within the accepted World Health Organization model may usefully leverage limited ophthalmological capacity in emerging economies. Adjunctive FDT testing may further improve VT referral efficiency.