Validation of a computerised logMAR visual acuity measurement system (COMPlog): comparison with ETDRS and the electronic ETDRS testing algorithm in adults and amblyopic children

Abstract

COMPlog measurements agree well with and are similarly reliable to the gold standard ETDRS chart with comparable test times. E-ETDRS algorithm measurements took approximately twice as long.

Validation of printed and computerised crowded Kay picture logMAR tests against gold standard ETDRS acuity test chart measurements in adult and amblyopic paediatric subjects

“…These results for each technique are typical of those published in other studies of the TRV of logMAR acuity measurements [5][6][7][8][9][10][11][12][13][14][15] in which TRV of acuity measurements of up to 0.2 logMAR (two logMAR lines) are observed in patients with unchanged acuity. These data suggest that the CKP tests are similarly repeatable to ETDRS chart acuity measurements.…”

“…The COMPlog Testing algorithm consists of two phases: 'range finding' and 'thresholding', which has been described in detail in previous publications. 5,6 Essentially, the range-finding phase presents single optotypes surrounded by a crowding box to determine approximate threshold acuity. The thresholding phase then displays sequentially smaller single lines of optotypes surrounded by a crowding box.…”

“…For ETDRS logMAR acuity charts, changes of up to 10 logMAR letters (2 logMAR lines) in either direction are recognised to occur. [5][6][7][8][9][10][11][12][13][14][15] This aspect of the performance of Kay picture acuity measurements has also not previously been investigated.…”

“…The development of computerised acuity measurement devices such as the E-ETDRS algorithm 8,16,17 and COMPlog visual acuity measurement system, 5,6 as well as computerised test chart presentation devices such as Test Chart 2000, means the reliability of computerised presentation of test stimuli should be investigated.…”

Performance of a computerised visual acuity measurement device in subjects with age-related macular degeneration: comparison with gold standard ETDRS chart measurements

“…12 Over the years, a number of computerised VA measurement systems have been developed as an alternative to standard printed acuity charts in an attempt to semi-automate the measurement process [13][14][15] and have proposed a number of advantages over the ETDRS chart. Measurement rigour is better controlled and standardized.…”