Aim: The Hardy‐Rand‐Rittler (HRR) pseudoisochromatic test for colour vision is highly regarded but has long been out of print. Richmond Products produced a new edition in 2002 that has been re‐engineered to rectify shortcomings of the original test. This study is a validation trial of the new test using a larger sample and different criteria of evaluation from those of the previously reported validation study.

Methods: The Richmond HRR test was given to 100 consecutively presenting patients with abnormal colour vision and 50 patients with normal colour vision. Colour vision was diagnosed using the Ishihara test, the Farnsworth D15 test, the Medmont C‐100 test and the Type 1 Nagel anomaloscope. Results: The Richmond HRR test has a sensitivity of 1.00 and a specificity of 0.975 when the criterion for failing is two or more errors with the screening plates. Sensitivity and specificity become 0.98 and 1.0, respectively, when the fail criterion is three or more errors.

Those with red‐green colour vision deficiency were correctly classified as protan or deutan on 86 per cent of occasions, with 11 per cent unclassified and three per cent incorrectly classified. All those graded as having a ‘mild’ defect by the Richmond HRR test passed the Farnsworth D15 test and had an anomaloscope range of 30 or less. Not all dichromats were classified as ‘strong’, which was one of the goals of the re‐engineering and those graded as ‘medium’ and ‘strong’ included dichromats and those who have a mild colour vision deficiency based on the results of the Farnsworth D15 test and the anomaloscope range. Conclusions: The test is as good as the Ishihara test for detection of the red‐green colour vision deficiencies but unlike the Ishihara, also has plates for the detection of the tritan defects. Its classification of protans and deutans is useful but the Medmont C‐100 test is better.

Those graded as ‘mild’ by the Richmond HRR test can be regarded as having a mild colour vision defect but a ‘medium’ or ‘strong’ grading needs to be interpreted in conjunction with other tests such as the Farnsworth D15 and the anomaloscope. The Richmond HRR test could be the test of choice for clinicians who wish to use a single test for colour vision. The HRR pseudoisochromatic test was developed by Hardy, Rand and Rittler, and was first published by the American Optical Company in 1955. It has been much loved by the cognoscenti of colour vision because it included plates to detect tritan colour vision deficiency, as well as the protan and deutan deficiencies and had a carefully designed set of plates to differentiate protan, deutan and tritan deficiencies and grade their severity. The HRR provided the clinician with more information than the Ishihara in a test that was just as easy to administer. The Ishihara test, renowned for its high sensitivity and excellent specificity for the detection of protan and deutan deficiencies, has no tritan plates and the number of errors made gives little indication of severity. - Moreover, its four protan‐deutan classification plates are not very reliable., A second edition of the HRR test was published in 1957, using material from the first print run but with a rearrangement of the order of the plates.

The tune is goodeverybody is acting well and are justifying their roleswhich means the Director of this play is very experienced and a class DirectorAll credit goes to him it is played every evening 7 pm and repeated at 11:00 pm.Monday to Saturday for 1 hour Tomorrow when hande takes all her friends for her birthday to a hotelthey will find Feriha working as a waitress there. Hello, I’m from the Philippines. Cant wait to see what happens next.i saw in the you tubesomeone kills her on her marriage day can some body tell me who killef her??? I watched AFK with english subtitle thru one of hazal kaya fanpage (fb) and I must say that the series is good. Actually, i love it. Svadjba emira i feriha in english.

Hell quest 09 free full. If u don't have one your drop rates are looking between 4% and 5% which is near impossible no matter how long u try. However I do like the fact that daily missions double your chances of receiving a dice it's just too unforgiving for those without premium. But that was until I realized that I was playing wit a premium account which doubles all drop rates.

Jan 31, 2012 - EQUIPMENT. EDITION PLATES. Pseudoisochromatic plates.

No further editions were published by the American Optical Company and the test has not been available for many years. Richmond Products, a US‐based manufacturer of ophthalmic equipment, published a replica of the test in 1991 but this was not an exact copy of the original test and it was not well received.

On the basis of his colorimetric analysis, Dain concluded that it was ‘a pale imitation of the real thing’. Richmond Products published a further edition in 2002, the colours of which have been carefully re‐engineered with the assistance of Jay and Maureen Neitz and James Bailey. The re‐engineering of the test has moved the colours nearer to the dichromatic confusion lines and has used a revised deutan copunctal as the origin of the deutan confusion lines based on new knowledge gained since the HRR test was first designed. In addition, the colours of the characters on some plates were desaturated slightly, so that dichromats would be graded as having a severe colour deficiency, which was not always the case in the original HRR test.

Colorimetric analyses of the new HRR test, suggest that it should perform better in differentiating protans and deutans and in grading severity. The design of the HRR test is based on very sound principles. It comprises 24 plates each displaying either one or two symbols, which can be a cross, a circle or a triangle (). The symbols are constructed of coloured dots on a background of grey dots. The coloured dots have chromaticity co‐ordinates that lie on or close to the protan, deutan or tritan dichromatic confusion loci that pass through the chromaticity co‐ordinates of the grey background colours.