title: A customised portable LogMAR chart with adjustable chart illumination for use as a mass screening device in the rural population.
abstract: OBJECTIVE
  To develop a customised, portable, cost-effective (logarithmic minimal angle resolution) LogMAR chart with adjustable illumination for use as a mass vision-screening device in the rural population.
  
  
  METHODS
  Visual acuity of 100 individuals was evaluated with a customised chart and compared with the standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart and Snellen's Chart. Bland and Altman analytical techniques were used for analysis.
  
  
  RESULTS
  Test-retest variability of the customised chart was just a one-line difference (95% CI for agreement), and so were the results with the standard ETDRS charts; a variability of 3-line was noted with Snellen's chart. Two-line differences were observed when comparison was made with Standard ETDRS chart and 2 to 3-line differences with Snellen's chart.
  
  
  CONCLUSIONS
  The customised portable LogMAR chart with adjustable illumination shows less test-retest variability and better agreement with standard ETDRS chart; therefore, it can be used as a mass vision-screening device in rural settings.
authors: Sankara Nethralaya, 18 College Road, Chennai-600006, Tamil Nadu, India.
authors: M
authors: M
authors: Gouthaman
authors: R P
authors: RP
authors: Raman
authors: A
authors: A
authors: Kadambi
authors: R
authors: R
authors: Padmajakumari
authors: P G
authors: PG
authors: Paul
authors: T
authors: T
authors: Sharma
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D019035:Rural Health Services; D012424:Rural Population; D015351:Vision Screening / Q000295:instrumentation*