Free Download Ishihara 38 Plates Pdf

Purpose: To compare the standard Ishihara booklet with color-vision-testing smartphone applications. Methods: A prospective observational diagnostic study on 42 normal trichromats and 38 color-deficient subjects. Patients were presented with three color vision tests in random order: an Ishihara test booklet and two color-vision-testing smartphone applications: Eye2Phone and the Color Vision Test application (CVT app). Sensitivity and specificity of the electronic tests was compared with Ishihara results, and in each one of these applications every plate was individually analyzed for success/failure rate. Results: Average age was 42.7 ± 12.9 years. There were 57 males (71.2%). Sensitivity and specificity of each test was 100% (38/38) and 95.2% (40/42) for the Eye2Phone, and 100% (38/38) and 54.8% (23/42) for the CVT app. There was no significant difference between the Ishihara booklet and the Eye2Phone (p = 0.500), with a high kappa measure of agreement (0.950, p < 0.001). The CVT app was significantly different than both other tests (p < 0.001) with a low kappa measure of agreement (0.535 with the Ishihara and 0.575 with the Eye2Phone). Of the 21 tested plates, color-deficient subjects failed 11.8 ± 3.1 plates in the Ishihara booklet and 14.1 ± 2.1 plates in the Eye2Phone (p < 0.001). Significant plate-specific differences for the color-deficient group were found in plate numbers 3, 6, 7, 8, 9, 15, and 16. Both tests were poorly able to give an indication of the specific dichromatism type. The Ishihara booklet was rated more comfortable and clearer than the Eye2Phone in color-deficient subjects. The CVT app was rated lowest for comfort and clarity in both groups. Conclusions: Smartphone applications testing for color vision deficiency are readily available; however, users of these apps should be aware that some may have different sensitivity for detection of color vision deficiency compared to Ishihara booklet, limiting their usefulness for clinical use. Therefore, further validation of these applications is required.

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Comparison of Ishihara Booklet with Color

Vision Smartphone Applications

Nir Sorkin*, Amir Rosenblatt*, Eyal Cohen*, Oded Ohana*,

Chaim Stolovitch*, and Gad Dotan*

ABSTRACT

Purpose. To compare the standard Ishihara booklet with color-vision-testing smartphone applications.

Methods. A prospective observational diagnostic study on 42 normal trichromats and 38 color-deficient subjects. Patients

were presented with three color vision tests in random order: an Ishihara test booklet and two color-vision-testing

smartphone applications: Eye2Phone and the Color Vision Test application (CVT app). Sensitivity and specificity of the

electronic tests was compared with Ishihara results, and in each one of these applications every plate was individually

analyzed for success/failure rate.

Results. Average age was 42.7 T 12.9 years. There were 57 males (71.2%). Sensitivity and specificity of each test was 100%

(38/38) and 95.2% (40/42) for the Eye2Phone, and 100% (38/38) and 54.8% (23/42) for the CVT app. There was no sig-

nificant difference between the Ishihara booklet and the Eye2Phone (p = 0.500), with a high kappa measure of agreement

(0.950, p G 0.001). The CVT app was significantly different than both other tests (p G 0.001) with a low kappa measure of

agreement (0.535 with the Ishihara and 0.575 with the Eye2Phone). Of the 21 tested plates, color-deficient subjects failed

11.8 T 3.1 plates in the Ishihara booklet and 14.1 T 2.1 plates in the Eye2Phone (p G0.001). Significant plate-specific

differences for the color-deficient group were found in plate numbers 3, 6, 7, 8, 9, 15, and 16. Both tests were poorly

able to give an indication of the specific dichromatism type. The Ishihara booklet was rated more comfortable and clearer

than the Eye2Phone in color-deficient subjects. The CVT app was rated lowest for comfort and clarity in both groups.

Conclusions. Smartphone applications testing for color vision deficiency are readily available; however, users of these apps

should be aware that some may have different sensitivity for detection of color vision deficiency compared to Ishihara

booklet, limiting their usefulness for clinical use. Therefore, further validation of these applications is required.

(Optom Vis Sci 2016;93:667Y672)

Key Words: Ishihara, color vision, smartphone, applications, comparison

Color vision tests commonly used in clinical practice in-

clude pseudoisochromatic plate tests such as the Ishihara

test

and the Hardy-Rand-Rittler (HRR) test,

and color

arrangement tests such as the Farnsworth-Munsell 100 hue test.

The Ishihara test is used for rapid screening of red-green color

defects, also providing initial information regarding the dichro-

matism type (protan or deutan). Congenital color vision defects are

present in a largepart of the population (up to 8% of malesand 0.5%

of females), and its presence can have occupational or educational

implications.

4,5

Color vision assessment is usually performed as part

of routine ophthalmological examination.

Ishihara testing is performed using a standard booklet, con-

taining either 38 plates (full version), 24 plates (abbreviated ver-

sion), or 14 plates (concise version). Availability limitations include

the cost of the booklet, its physical availability, and natural wear and

tear. Previous studies reported that clinicians waste significant time

each day in search of an Ishihara booklet that is commonly shared

between them.

Other studies found that in older Ishihara booklets,

there is a shift of colorimetric values with plate aging, potentially

leading to inaccurate test results.

Widespread availability of smartphones and tablet computers

led to the development of numerous healthcare software appli-

cations in all fields of medicine, including ophthalmology.

Many

applications designed for color vision testing are available for use

with modern smartphones. These offer an alternative to color

vision booklets that is more affordable, widely available, and may

show less wear with prolonged use. These applications are widely

1040-5488/16/9307-0667/0 VOL. 93, NO. 7, PP. 667Y672

OPTOMETRY AND VISION SCIENCE

ORIGINAL ARTICLE

Optometry and Vision Science, Vol. 93, No. 7, July 2016

*MD

Department of Ophthalmology, Tel Aviv Medical Center, Sackler Faculty of

Medicine, Tel Aviv University, Tel Aviv, Israel (all authors).

used despite the fact that they have not yet been validated in the

literature. Smartphone applications employ a principle similar to

the Ishihara pseudoisochromatic plates. Some of the applications

are exact duplicates of the Ishihara booklet whereas others contain

different designs of pseudoisochromatic plates.

Current smartphone displays use advanced variants of liq-

uid crystal display (LCD) or light emitting diode (LED) tech-

nology (e.g. thin film transistor LCD (TFT-LCD), organic-light

emitting diode (OLED)). Research of the visual perception

of TFT-LCD displays showed that visual perception time was

good for the primary colors but only moderate for middle-point

colors, and that change in ambient illumination level and lumi-

nance contrast ratio had significant effects on visual perception

of those displays.

Previous studies of electronic color vision

tests evaluated customized color vision tests, displayed either on

large personal computer displays

10Y12

or on obsolete, cathode

ray tube (CRT) monitors.

To the best of our knowledge, the use

of electronic Ishihara tests on small-sized TFT-LCD displays,

such as those in smartphones and tablet computers, has not

been evaluated.

In this study, we compared color vision testing using two

smartphone applications to the standard Ishihara booklet in

normal trichromats and color-deficient subjects.

PATIENTS AND METHODS

This prospective observational diagnostic study included adults

(9 18 years) who were classified as normal trichromats or color

deficient, according to the results of the Ishihara booklet test. As

previously reported, almost all color-deficient subjects fail this test

when it is performed correctly.

14,15

All participants had a visual acuity of 20/20 in either eye and were

able to classify correctly at least the first (false) plate in the Ishihara

booklet. None had any known ocular pathology that can potentially

affect color vision such as advanced cataract, retinal degeneration,

any retinopathy, or optic neuropathy. Approval for this study was

granted by the Institutional Review Board of our medical center,

and its conduction was in accordance with the rules and regulations

of the Declaration of Helsinki. All participants gave their written

informed consent to take part in this study.

Color Vision Tests

Patients were presented with three color vision tests in random

order: a full 38-plate Ishihara test (on a newly purchased booklet

to avoid the influence of wear and tear on test quality

) (Fig. 1A)

and two smartphone applications designed for color vision testing

for the iPhone 3Gs (Apple Inc., Cupertino, CA) which has a TFT-

LCD screen. The first application was the Eye2Phone v. 1.0 (Neosono,

Barcelona, Spain; Renato Neves MD, Eye Care HospitalV Sao

Paulo, Brazil). This application is an exact duplicate of the full

38-plate Ishihara test, with screen-sized plates (Fig. 1B). In this

app, the subject manually slides each plate on the screen to be

presented with the next plate. The second application was the

Color Vision Test (CVT) (Rila Software, Dublin, Ireland). This

application contains 16 pseudoisochromatic plates, of which some

are identical to those of the Ishihara booklet plates, whereas others

are completely different than it. The test is presented in the form

FIGURE 1.

Example of a test plate taken from the Ishihara booklet (A), Eye2Phone (B), and Color Vision Test (CVT) app (C). Plate size ratios are in accordance with

the true physicalratio between theIshihara bookletand the smartphonescreen. True plate diameters are 85, 45,and 29 mm for the Ishihara booklet,Eye2Phone,

and CVT app, respectively.

668 Smartphone Color Vision TestsV Sorkin et al.

Optometry and Vision Science, Vol. 93, No. 7, July 2016

of multiple choiceV the superior half of the screen contains the

pseudoisochromatic plate and the inferior half contains six possible

answers, one of which is selected by the subject (Fig. 1C). In the

Ishihara booklet and the Eye2Phone application, plates 1 through

25 (of 38 plates) were evaluated, and in the CVT application all 16

plates were evaluated.

Testing was performed binocularly under normal ambient room

lighting conditions, using daylight fluorescent lamps (color tem-

perature of about 6500 K). The illuminance at the level of testing

was 500 lux. Smartphone screen brightness was set to maximum.

The measured smartphone luminance level at maximal brightness

was 430 cd/m

. Subjects were allowed to choose testing position and

distance most comfortable for them, but were required to use the

same position and distance for both the smartphone and the Ishihara

booklet testing. Subjects were allowed three seconds to answer each

plate. Each of their replies was then recorded on a dedicated form.

At the conclusion of all tests, subjects were asked to grade the

comfort level and clarity of each test on a scale of 1 to 5, and were

given the possibility to remark freely on the tests.

Test Scoring

The ability of each smartphone application to diagnose normal

trichromats and color-deficient subjects was compared with the

Ishihara booklet. In the Ishihara booklet and the Eye2Phone, a

subject with five or more plate errors in plates 1 to 21 was defined

as ''Color Deficient,'' and a subject with four or less plate errors in

plates 1 to 21 was defined as ''Normal,'' as previously reported by

Cole et al.

The CVT software outputs an automatic result: either

''Normal'' if all 16 plates are read correctly or ''Color Deficient'' if

15 or less are read correctly. Sensitivity and specificity was cal-

culated for each of the tests and compared.

Each plate in each of the tests was also individually analyzed

for success rate in normal trichromats and failure rate in color-

deficient subjects. Because the plates in the Ishihara booklet and

the Eye2Phone are identical, a direct comparison of each indi-

vidual plate was performed between the Ishihara booklet and the

Eye2Phone.

A legend detailing which numbers are recognized in each plate

by normal and color-deficient subjects is given in Table 1. The

Ishihara booklet and Eye2Phone naturally have an identical leg-

end whereas the CVT has a different one (Table 2). A scoring

system for the degree of compatibility of each test with its legend

was established: a score of 1 point was given to a plate where the

number recognized was an exact match of the number specified for

this plate in the legend, and a score of 0.5 a point was given to a

plate where the number recognized matched the number in the

legend by only one digit (for example: if plate 9, which should

be recognized as the number 21 by a color-deficient subject, was

viewed as 71, the score given was 0.5). Compatibility scores were

compared between the tests.

Plates 22 to 25 in the Ishihara test (Ishihara booklet and the

Eye2Phone) are designed to give preliminary indication whether the

color deficiency found is of protan or deutan nature (Table 1). We

also compared the Ishihara booklet and the Eye2Phone in terms of

successful indication of the color deficiency type (protan or deutan).

Statistical Analysis

Data were recorded in Microsoft Excel and analyzed using SPSS

version 21 (SPSS Inc., Chicago, IL).

TABLE 1.

Answer legend for each plate of the Ishihara booklet and

Eye2Phone application when viewed by normal or red-green

color-deﬁcient subjects

Plate No. Normal trichromat Red-green deficient

112 12

28 3

36 5

429 70

557 35

65 2

73 5

815 17

974 21

10 2 X

11 6 X

12 97 X

13 45 X

14 5 X

15 7 X

16 16 X

17 73 X

18 X 5

19 X 2

20 X 45

21 X 73

Deutan Protan

22 26 2 6

23 42 4 2

X, no number identified.

TABLE 2.

Answer legend for each plate of the Color Vision Test

(CVT) application when viewed by normal or red-green

color-deﬁcient subjects

Plate No. Normal trichromat Red-green deficient

183

25X

37X

415 5

57414

62920

71212

838

973 X

10 16 X

11 45 X

12 5 X

13 5 2

14 2 X

15 74 X

16 97 X

X, no number identified.

Smartphone Color Vision TestsV Sorkin et al. 669

Optometry and Vision Science, Vol. 93, No. 7, July 2016

Continuous variables, such as age, were compared within subjects

using paired t-test and between subjects using the independent

sample t-test. For paired comparisons of small groups and ordinal

variables such as test ratings, the Wilcoxon paired nonparametric

test was used. The Friedman nonparametric test was performed for

multiple within-subject comparisons. Binary variables were com-

pared within subjects using the McNemar test for symmetry and

between subjects using the Fisher exact test or Pearson chi-square

test. Agreement between the results of tests was analyzed using

Cohen's kappa measure of agreement. Sensitivity was calculated as

the percentage of successful diagnosis of color-deficient subjects.

Specificity was calculated as the percentage of successful determi-

nation of normal trichromats.

All tests were two-tailed, and the threshold for statistical sig-

nificance was defined as a p value G0.05.

RESULTS

Eighty subjects were included in this study. There were 57 males

(71.2%) and the average age of all subjects was 42.7 T 12.9 years.

Forty-two subjects (53%) were classified as normal trichromats,

and 38 subjects (48%) were classified as color deficient. There was

no statistical difference (p = 0.450) between mean age of color-

deficient subjects (43.9 T 12.4 years) and normal trichromats

(41.7 T 13.3 years).

Diagnosing Normal and Color-Deficient Subjects

Sensitivity and specificity of each test was 100% (38/38) and

95.2% (40/42) for the Eye2Phone, and 100% (38/38) and 54.8%

(23/42) for the CVT app.

There was no significant difference between the Ishihara

booklet and the Eye2Phone (p = 0.500). The kappa measure of

agreement was high (0.950, p G0.001).

The CVT app was significantly different than both the Ishihara

booklet and the Eye2Phone (p G 0.001 in both comparisons). The

kappa measure of agreement was relatively low (0.535, p G0.001

and 0.575, p G 0.001, respectively).

The average number of plates identified correctly by normal

trichromats in the Ishihara booklet and the Eye2Phone was 20.6 T

0.8 and 20.1 T 2.4, respectively. This difference was not statisti-

cally significant (p = 0.055). The average number of plates not

identified correctly by color-deficient subjects in the Ishihara

booklet and the Eye2Phone was 11.8 T 3.1 and 14.1 T 2.1, re-

spectively. This difference was statistically significant (p G0.001).

Individual Plate Success

Each individual plate was compared between the Ishihara

booklet and the Eye2Phone. Successful identification rates of each

plate were compared in normal trichromats (Table 3), and failed

identification rates of each plate were compared in color-deficient

subjects (Table 4). In the normal trichromat group, there were no

significant differences between the tests in success rates in any of

the plates. Significant differences in failed identification rates were

found in the color-deficient group in plate numbers 3, 6, 7, 8, 9,

15, and 16 (Table 4).

Test Compatibility With the Test Legends

In the color-deficient group, a comparison of compatibility

with the test legend (Table 1) between the Ishihara booklet and the

TABLE 3.

Individual plate-identiﬁcation success rateV comparison

between the Ishihara booklet and the Eye2Phone in normal

trichromats

Plate No. Ishihara booklet Eye2Phone p value

1 100% 100% V

2 100% 92.9% 0.250

3 97.6% 100% 1.000

4 100% 95.2% 0.500

5 97.6% 97.6% 1.000

6 100% 95.2% 0.500

7 97.6% 85.7% 0.125

8 97.6% 97.6% 1.000

9 90.5% 85.7% 0.625

10 100% 92.9% 0.250

11 100% 95.2% 0.500

12 90.5% 97.6% 0.250

13 100% 100% 1.000

14 100% 97.6% 1.000

15 100% 95.2% 0.500

16 100% 95.2% 0.500

17 92.9% 85.7% 0.250

18 100% 100% 1.000

19 100% 100% 1.000

20 100% 100% 1.000

21 100% 100% 1.000

*Statistically significant.

TABLE 4.

Individual plate-identiﬁcation failure rateV comparison

between the Ishihara booklet and the Eye2Phone in

color-deﬁcient subjects

Plate No. Ishihara booklet Eye2Phone p value

1 100% 100% V

2 84.2% 71.1% 0.302

3 97.4% 52.6% G0.001*

4 97.4% 100% 1.000

5 97.4% 100% 1.000

6 39.5% 97.4% G0.001*

7 31.6% 82.4% G0.001*

8 26.3% 73.7% G0.001*

9 81.6% 100% 0.016*

10 92.1% 97.4% 0.625

11 92.1% 94.7% 1.000

12 100% 97.4% 1.000

13 94.7% 97.4% 1.000

14 65.8% 63.2% 1.000

15 47.4% 92.1% G0.001*

16 34.2% 76.3% 0.002*

17 81.6% 97.4% 0.070

18 2.6% 2.6% 1.000

19 2.6% 5.3% 1.000

20 5.3% 2.6% 1.000

21 2.6% 2.6% 1.000

670 Smartphone Color Vision TestsV Sorkin et al.

Optometry and Vision Science, Vol. 93, No. 7, July 2016

Eye2Phone was made. Compatibility of the Ishihara booklet with

the test legend in color-deficient subjects was 7.4 T 2.5 plates.

Compatibility of the Eye2Phone with the test legend in color-

deficient subjects was 11.7 T 2.6 plates. The difference between

the tests was statistically significant (p G0.001).

Diagnosing Color Deficiency Type

Indication of color deficiency type (deutan or protan) was

successful in 11 of 38 patients (28.9%) and in 18 of 38 patients

(47.4%) in the Ishihara booklet and the Eye2Phone, respectively.

This difference was not statistically significant (p = 0.143). The

kappa measure of agreement between the tests in the ability to type

color deficiency was low (0.085, p = 0.572). Only six patients were

successfully typed by both tests. Of those six patients, four were

typed by both tests as deutan, one as protan, and one had

conflicting typing by each of the tests.

Subject Evaluation of Test Comfort and Clarity

Overall, subject rating of test comfort and clarity was 4.54 T

0.93, 4.12 T 0.96, and 3.40 T 1.23 for the Ishihara booklet,

Eye2Phone, and the CVT app, respectively. All differences were

statistically significant (p G 0.001).

Among normal trichromats, subject rating was 4.66 T 0.66,

4.43 T 0.74, and 3.59 T 1.21 for the Ishihara booklet, Eye2Phone,

and the CVT app, respectively. The CVT app was ratedsignificantly

lower than both Ishihara booklet and Eye2Phone (p G 0.001 com-

pared with both). Subject rating in this group was not statistically

different between Ishihara booklet and the Eye2Phone (p = 0.174).

Among color-deficient subjects, rating was 4.39 T 1.20, 3.71 T

1.07, and 3.16 T 1.24 for the Ishihara booklet, Eye2Phone, and

the CVT app, respectively. All differences were statistically sig-

nificant (Ishihara vs. Eye2Phone: p = 0.014, Ishihara vs. CVT app:

pG 0.001, Eye2Phone vs. CVT app: p = 0.006).

Subjects remarked mostly about increased comfort when using the

booklet, difficulty with the small-sized plates of the CVT app, and

difficultycausedbyglareandrefl ections from the smartphone screen.

DISCUSSION

In this study, we compared two color-vision-testing smartphone

applications with the Ishihara booklet. The CVT app was found

to be inferior to both the Ishihara booklet and the Eye2Phone: it

had a low specificity of 54.8% and was rated lowest by the users

with regard to comfort and clarity. Possible reasons for this are

the relatively small physical size of the pseudoisochromatic plates

(Fig. 1C), the test design as a multiple choice, and the allowance of

only one plate-error to be made before diagnosing color deficiency.

The Eye2Phone is designed to closely resemble the Ishiharabooklet

and, thus, avoids the above described issues. However, even though

they share similar design, significant differences between them still

exist when used in color-deficient subjects. These include the

number of falsely identified plates, individual plate-failure rates, and

compatibility with the test legend. In addition, the Ishihara booklet

received a higher comfortability score than the Eye2Phone app

and was perceived clearer than this app by color-deficient subjects.

These differences may be attributed to dissimilarities between the

platforms in plate size, contrast, brightness, and color saturation.

Plate size variation is substantial with physical plate diameter mea-

suring 85 mm in the Ishihara booklet and 45 mm in the Eye2Phone

(Fig. 1). A different visual perception of the plates on the TFT-LCD

screen may also contribute to the differences found.

studies compared the Ishihara booklet with electronic versions

displayed on obsolete CRT monitors

and with slide-projected

versions,

and found them to be comparable to the Ishihara

booklet. Interestingly, as detailed above, in color-deficient subjects

the Eye2Phone showed greater compatibility with the test legend

than the Ishihara booklet.

Both tests were poorly able to give an indication of the specific

dichromatism type (deutan or protan). Earlier studies found that

the Ishihara test has a high failure rate of 30 to 40% in differ-

entiating between deutan and protan subjects.

14,17

The reason is

that the plates designed to discriminate deutan and protan subjects

contain one numeral not seen by deutans and one numeral not

seen by protans. In cases where both numerals are seen or neither

numeral is seen, the test is unable to determine the color deficiency

type. In our study, it was evident that this flaw persists in the

Eye2Phone app which is a duplicate of the Ishihara booklet.

A limitation of our study is the lack of an additional gold-

standard test for the diagnosis of color deficiency in our sub-

jects, such as the use of a Nagel anomaloscope test, commonly

used in studies comparing color vision tests.

Another limitation

is the unavailability of the Eye2Phone app for newer versions

of iPhone. However, electronic applications are constantly

changing and it is impossible for any study to make sure that the

application used in it will be permanently available, but because

the Eye2Phone app is an exact duplicate of the Ishihara booklet,

there are several others like it, which are currently available for

newer smartphone models; therefore, the results of this study may

apply to these applications as well, but further studies are needed

for confirmation.

In conclusion, smartphone applications used for color vision

testing are more affordable than the Ishihara booklet, are widely

available, and may show less wear with prolonged use. How-

ever, different smartphone applications may have different effi-

cacy as shown here. Smartphone applications that closely resemble

the Ishihara booklet may be a good possible alternative clinically,

but differences from the Ishihara booklet exist. Differences in

smartphone screen size and screen technologies create a lack of

uniformity. In addition, the issue of size difference between the

smartphone screen and the Ishihara booklet should be further

studied, as is the issue of the ideal testing distance, which may

differ between the two, and thus reduce the angular size differ-

ence which exists between them when viewed from the same

distance. Further evaluation and validation of these applications

may be necessary, including a comparison with an additional gold-

standard test. It may be recommended for software designers to

provide evidence of validations performed of their app, and users

should seek evidence of those validations before using these apps

to interpret color vision status.

ACKNOWLEDGMENTS

Financial Support: None. Financial Interest: None.

Received March 21, 2015; accepted January 7, 2016.

Smartphone Color Vision TestsV Sorkin et al. 671

Optometry and Vision Science, Vol. 93, No. 7, July 2016

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selection. Aust J Optom 1964;47:56Y64.

Nir Sorkin

Department of Ophthalmology

Tel Aviv Medical Center

6 Weizmann Street

Tel Aviv 6423906

Israel

e-mail: nir_sorkin@yahoo.com

672 Smartphone Color Vision TestsV Sorkin et al.

Optometry and Vision Science, Vol. 93, No. 7, July 2016

... Seven (9%) related to high-risk medical device apps including apps for monitoring vital signs, 23,28 and diagnosis of disease including melanoma 29-32 and color blindness. 33 Almost half of the studies related to apps for managing a specific disease (n ¼ 34, 46%) with the remaining focusing on apps for wellness management, self-diagnosis, physical medicine, and medication reminders (Table 1; Supplementary Appendix C). Most studies involved apps that engaged consumers using 1 or more functionalities such as by displaying and summarizing user-entered information (n ¼ 54), tracking data (n ¼ 52), providing guidance (n ¼ 49), and educational information (n ¼ 49). ...

... 51 3. Variation in content: Apps that addressed similar domains were found to have significant differences in the quality of their content. 33,37,47,[57][58][59][60][61] For example, studies reported inconsistencies in the information presented and tools used in apps for obesity management, 58 physical activity measurement, 59 color vision assessment, 33 and medication self-management. 60 Likewise, apps for pain management required users to enter varying amounts of information to clinically assess symptoms. ...

Objective: To summarize the research literature about safety concerns with consumer-facing health apps and their consequences. Materials and methods: We searched bibliographic databases including PubMed, Web of Science, Scopus, and Cochrane libraries from January 2013 to May 2019 for articles about health apps. Descriptive information about safety concerns and consequences were extracted and classified into natural categories. The review was conducted in accordance with the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) statement. Results: Of the 74 studies identified, the majority were reviews of a single or a group of similar apps (n = 66, 89%), nearly half related to disease management (n = 34, 46%). A total of 80 safety concerns were identified, 67 related to the quality of information presented including incorrect or incomplete information, variation in content, and incorrect or inappropriate response to consumer needs. The remaining 13 related to app functionality including gaps in features, lack of validation for user input, delayed processing, failure to respond to health dangers, and faulty alarms. Of the 52 reports of actual or potential consequences, 5 had potential for patient harm. We also identified 66 reports about gaps in app development, including the lack of expert involvement, poor evidence base, and poor validation. Conclusions: Safety of apps is an emerging public health issue. The available evidence shows that apps pose clinical risks to consumers. Involvement of consumers, regulators, and healthcare professionals in development and testing can improve quality. Additionally, mandatory reporting of safety concerns is needed to improve outcomes.

... 5,8 Software-based colour vision tests and mobile applications have been recommended as a solution to this issue, yet the results of these tests differ due to differences in technology, screen resolution, size and variability because of external lighting levels. 9 Hence a screening test that would overcome these limitations is essential especially for large-scale screening programs. This study aimed to construct and validate a new colour vision screener to detect congenital CVD. ...

... 18 Earlier studies comparing smartphone-based applications to Ishihara's booklet have demonstrated a good sensitivity and specificity with few applications (Eye2Phone) 9,24 and a relatively poor specificity (colour vision test) with few other applications. 9 This difference was attributed to the technologies involved like the property of display, screen size and corresponding test plate size, glare and reflections from the smartphone screen. The Dalton PIP overcomes the disadvantages of these applications. ...

Background: Diagnosing colour vision deficiency is vital, owing to its impact on the choice of career and activities of daily living. Conventional screening methods require frequent replacement due to soiling of the materials, and hence are expensive and not feasible for large-scale community screening. This study aims to construct and validate a new screening tool, Dalton's pseudo-isochromatic plates (PIP), addressing the disadvantages of the conventional methods. Methods: The two phases of the study included the construction and validation of the Dalton's PIP. Construction involved utilising specific wavelengths based on spectral tuning, selection of numerals as targets for the chart and identification of a material with durability and resistance to wear and tear. Validation of the chart was done against the 38-plate edition of Ishihara's PIP by two masked examiners for 1,019 school children aged between 11-17 years (mean ± SD: 14 ± 2 years) as part of a school eye-health program. Results: The sensitivity and the specificity of the Dalton's PIP was found to be 94.12 per cent (95% CI 71.31-99.85) and 99.60 per cent (95% CI 98.98-99.89) respectively and the positive and negative predictive values were 80 per cent and 99.90 per cent respectively. Dalton's PIP when used with a failure criterion of less than three plates correct in two screening sets had the maximum sensitivity and specificity and the area under the curve was 0.96 (95% CI 0.90-0.99, p < 0.05). Conclusion: The newly constructed Dalton's PIP is found to be a valid screening tool to detect congenital colour vision deficiency and is comparable to the Ishihara PIP. This screening tool with its shorter screening time, cost and longer durability would effectively serve in large-scale vision screening programs.

... Some stereotests are available on specific smartphone app stores but their convergence validity (concordance) and agreement with standard tests are not reported. Without these data, the utility of the test is unknown [11]. ...

Purpose Stereopsis is a fundamental skill in human vision and visual actions. There are many ways to test and quantify stereoacuity: traditional paper and new digital applications are both valid ways to test the stereoacuity. The aim of this study is to compare the results obtained using standard tests and the new Stereoacuity Test App developed by the University of Bergamo. Methods A group of 497 children (272 males), aged between 6 and 11 years old, were tested using different tests for the quantification of stereopsis at near. These tests were TNO, Weiss EKW, and the new developed Stereoacuity Test App. Results A one-way repeated measure ANOVA showed that the three tests give different thresholds of stereoacuity (p < 0.0001). Post hoc analyses with Bonferroni correction showed that all tests showed different thresholds (p < 0.0001). The lower threshold was obtained by Titmus Stereo Test followed by Stereoacuity App, Weiss MKW, and TNO. Conclusion The stereoacuity based on global stereopsis showed that the better values were obtained in order by Stereoacuity Test App, TNO, and Weiss EKW. However, the clinical significance of their values is similar. The new digital test showed a greater compliance by the child, showing itself in tune with the digital characteristics of today's children.

... Mobile phones and Internet-based telecommunication tools could also be used for remote eye care management and bedside monitoring with video assessment and patient-doctor interaction [54]. Moreover, patients, especially females and the elderly, could be trained on available self-testing mobile-applications that could be incorporated into the teleconsultation programmes to offer general and specialized eye care (e.g., optometry and vitreoretinal services, visual field testing) [55][56][57][58][59][60][61][62][63][64][65][66]. With teleconsultation, cybersecurity and limited online payment platforms may be concerning; hence, efforts are needed to address these issues. ...

Objective To evaluate the utility of teleconsultation in the provision of eye care services during the COVID-19 lockdown. Disparities in the consultation burden of sub-specialities and socio-demographic differences in teleconsultation utilization were also assessed. Methods Al-Shifa Trust Eye Hospital Rawalpindi began audio and video teleconsultation using broadband telecommunication services during the lockdown. Patients' and consultations' data gathered during the first three weeks after the commencement of this programme were compared with data from the four weeks prior to lockdown. The weekly consultation ratio and overall consultation burden of sub-specialities were measured. Chi-Square tests of association determined the relationship between different variables (socioeconomic status and consultation characteristics) and consultation modality (on-site vs online). Results In total, 17507 on-site consultations (4377/week) were conducted compared to 1431 teleconsultations (477/week), which maintained 10.89% of the weekly pre-lockdown eye care services. The post-lockdown teleconsultation programme saw a relatively higher percentage of service utility among female (47.09% vs 44.71%), younger-age (31.33±19.45 vs 41.25±23.32 years) and higher-socioeconomic-status (32.21% vs 0.30%) patients compared to pre-lockdown on-site consultations. The most common indication for teleconsultation was red-eye (16.70%). While cornea and glaucoma clinics maintained most of the pre-lockdown services (30.42% and 29% respectively), the highest dropout was seen in optometric and vitreoretinal services supporting only 5.54% and 8.28% of pre-lockdown services, respectively. Conclusion Digital initiatives could partially maintain eye care services during the lockdown. Focused strategies to improve teleconsultation utilization are required during the pandemic and beyond.

... The app was validated against the Ishihara color vision test in 2 clinical studies (14,15), although a nonclinical study using image analysis found it likely underestimates color vision loss severity in patients with normal contrast sensitivity (CS) and does not contain as many specially designed plates as Ishihara for differentiation of R-G deficiency from total color blindness (8). Other less promising apps include "Color Blind Test" (16) and "Color Vision Test" (17). Refer to Table 2 for color validation studies. ...

... The first part of the form contained demographics (age, gender), previous history of ocular abnormalities, visual acuity disorders, color vision deficiency, and family history of color blindness. Each participant was assessed for color vision using 24-plate Ishihara's Test of Color Vision using smartphone which was validated earlier by Sorkin et al. [10] The participants were instructed not to elapse >5 s on each plate. They kept a distance of 75 cm from the color vision testing plates. ...

KhaledA Alqurashi
Ashjan Yousef Bamahfouz
BayanMutlaq Almasoudi

PURPOSE: To estimate the prevalence of allergic conjunctivitis (AC) and its related allergic ailments among Saudi adults in the western region. METHODS: Adult population of Taif, Makkah, and Jeddah cities was surveyed from 2017 to June 2018. Subjective questionnaire was used to collect the response. Participants were asked about symptoms (redness, itching, watering, based diagnosis and details of AC, treatment taken in the pasts, and associated conditions, such as allergic asthma and rhinitis). The age-sex-adjusted prevalence, its determinants, and associations to other ailments were assessed. RESULTS: We surveyed 2187 participants (mean age 26.0 ± 9.1 years). The age-sex-adjusted prevalence of AC was 70.5% (95% confidence interval [CI] 68.6–72.4). There could be 2.1 million AC patients among 3.1 million adult populations in Western KSA. It was significantly higher in females compared to males (odds ratio [OR] = 1.7 [95% CI 1.4–2.2]). The risk of AC did not vary by age group (χ2 = 2.5, df = 3, P = 0.1). The variation of AC in three provinces was not significant (χ2 = 0.3, df = 3, P = 0.6). Dust (42.6%) and unknown (24.8%) allergens were the main causative agents of AC. AC was significantly associated to asthma (OR = 2.8) and allergic rhinitis (OR = 2.2). CONCLUSION: AC affects seven in ten adults in Western Saudi Arabia. AC is positively associated to allergic rhinitis and bronchial asthma. Public health policies at primary eye-care level should focus on early detection and care of persons with AC.

Purpose: To estimate the magnitude and determinants of color vision defects (CVD) among preparatory health science students. Methods: A cross-sectional survey was conducted in 2017. Participants were assessed using 24-plate Ishihara's Test of Color Vision chart. If ≤9 plates were read correctly, the color vision was regarded as deficient. The CVD prevalence and its 95% confidence interval (CI) were calculated. CVD was associated with gender, family history of CVD, and other vision problems. Results: We evaluated 1126 students (552, 49% males; mean age: 18.7 ± 0.7 years). The prevalence of CVD was 1.77% (95% CI: 1.0, 2.6). Among male students, it was 3.5% (95% CI: 1.9, 5.0). Only one female student had CVD. The Duran CVD was found in 18 (1.6%) students. However, only two students had Tritan CVD. Three among twenty CVD students knew that they suffer from CVD. CVD was positively associated to a family history of CVD (odds ratio [OR] = 3.8; 95% CI: 1.4, 10.1;P = 0.02) and male gender (OR = 20.4 [95% CI: 2.7, 153]). CVD was not significantly associated to other vision problems (OR = 0.8 [95% CI: 0.3, 2.0]). Conclusion: Eighteen in thousand health sciences students suffered from CVD. Ten percent of them had Tritan CVD. Duran CVD seems to be a male sex-related and/or a familial condition. Most of the CVD students seem to have adopted to this defect and were not aware of suffering from it. Screening for CVD is therefore debatable.

The W-D15 test, a computerized variant of the F-D15 test, is used to determine whether an individual with a color vision defect can safely perform color-related tasks. This study evaluated the performance of the W-D15 test using an iPad. Fifty-nine color normal and 61 color vision defect subjects participated. Participants were screened based on the Ishihara, City University Test, and Waggoner PIP24 tests. Different failure criteria of the D15 tests were considered. The pass/failure agreement between the two tests was relatively appropriate, with a 𝜅-coefficient ≥0.8, for all failure criteria. The W-D15 could be an appropriate substitute for F-D15 using an iPad.

Rachel Marjorie Wei Wen Tseng
Yih-Chung Tham
Tyler Hyungtaek Rim
Ching-yu Cheng

The prominent rise of digital health in ophthalmology is evident in the current age of Industry 4.0. Despite the many facets of digital health, there has been a greater slant in interest and focus on artificial intelligence recently. Other major elements of digital health such as mobile health could also substantially impact patient‐focused outcomes but have been relatively less explored and discussed. In this review, we adopted a narrative approach to comprehensively evaluate the use of non‐AI digital health tools in ophthalmology. 53 papers were included in this systematic review, with 25 papers dealing with virtual or augmented reality, 14 with mobile applications, and 14 with wearables. Most papers focused on the use of these technologies to detect or rehabilitate visual impairment, glaucoma and age‐related macular degeneration. Overall, the findings present encouraging improvements on patient‐focused outcomes with the adoption of these technologies. Further validation or large‐scale studies and earlier consideration of real‐world barriers are warranted to enable better real‐world implementation.

Smart phones are being increasingly used among health professionals. Ophthalmological applications are widely available and can turn smart phones into sophisticated medical devices. Smart phones can be useful instruments for the practice of evidence-based medicine, professional education, mobile clinical communication, patient education, disease self-management, remote patient monitoring or as powerful administrative tools. Several applications are available for different ophthalmological examinations that can assess visual acuity, color vision, astigmatism, pupil size, Amsler grid test and more. Smart phones can be useful ophthalmic devices for taking images of anterior and posterior eye segment. Professional literature and educational material for patients are easily available with use of smart phones. Smart phones can store great amount of informations and are useful for long term monitoring with caution for patient confidentiality. The use of smart phones especially as diagnostic tools is not standardized and results should be carefully considered. Innovative role of smartphone technology and its use in research, education and information sharing makes smart phones a future of ophthalmology and medicine.

Chin-Chiuan Lin
Kuo-Chen Huang

An empirical study was carried out to examine the effects of color combination and ambient illumination on visual perception time using TFT-LCD. The effect of color combination was broken down into two subfactors, luminance contrast ratio and chromaticity contrast. Analysis indicated that the luminance contrast ratio and ambient illumination had significant, though small effects on visual perception. Visual perception time was better at high luminance contrast ratio than at low luminance contrast ratio. Visual perception time under normal ambient illumination was better than at other ambient illumination levels, although the stimulus color had a confounding effect on visual perception time. In general, visual perception time was better for the primary colors than the middle-point colors. Based on the results, normal ambient illumination level and high luminance contrast ratio seemed to be the optimal choice for design of workplace with video display terminals TFT-LCD.

Clinical color vision evaluation has been based primarily on the same set of tests for the past several decades. Recently, computer-based color vision tests have been devised, and these have several advantages but are still not widely used. In this study, we evaluated the Waggoner Computerized Color Vision Test (CCVT), which was developed for widespread use with common computer systems. A sample of subjects with (n = 59) and without (n = 361) color vision deficiency (CVD) were tested on the CCVT, the anomaloscope, the Richmond HRR (Hardy-Rand-Rittler) (4th edition), and the Ishihara test. The CCVT was administered in two ways: (1) on a computer monitor using its default settings and (2) on one standardized to a correlated color temperature (CCT) of 6500 K. Twenty-four subjects with CVD performed the CCVT both ways. Sensitivity, specificity, and correct classification rates were determined. The screening performance of the CCVT was good (95% sensitivity, 100% specificity). The CCVT classified subjects as deutan or protan in agreement with anomaloscopy 89% of the time. It generally classified subjects as having a more severe defect compared with other tests. Results from 18 of the 24 subjects with CVD tested under both default and calibrated CCT conditions were the same, whereas the results from 6 subjects had better agreement with other test results when the CCT was set. The Waggoner CCVT is an adequate color vision screening test with several advantages and appears to provide a fairly accurate diagnosis of deficiency type. Used in conjunction with other color vision tests, it may be a useful addition to a color vision test battery.

LEGRAND H. HARDY
G RAND
M C RITTLER

The Ishihara test for color-blindness, taken as a representative type of polychromatic tests, fails to give more than a superficial evaluation of the state of an observer's color vision. It can be utilized as a good rough screening test for red-green color blindness, but in so doing most of the plates could be discarded. The results obtained are dependent to a large extent upon the illuminant used, and this fact militates against the deuteranomalous observer. The test gives neither an adequate qualitative (type of defect) nor quantitative (extent of defect) diagnosis, and may give a wrong diagnosis. Results obtained by this test should be discounted unless verified by other modern types of tests.

Barry L Cole PhD, MAppSc, BSc, LOSc

All people with abnormal colour vision, except for a few mildly affected deuteranomals, report that they experience problems with colour in everyday life and at work. Contemporary society presents them with increasing problems because colour is now so widely used in printed materials and in computer displays. Equal opportunity law gives them protection against unfair discrimination in employment, so a decision to exclude a person from employment on the grounds of abnormal colour vision must now be well supported by good evidence and sound argument. This paper reviews the investigations that have contributed to understanding the nature and consequences of the problems they have. All those with abnormal colour vision are at a disadvantage with comparative colour tasks that involve precise matching of colours or discrimination of fine colour differences either because of their loss of colour discrimination or anomalous perception of metamers. The majority have problems when colour is used to code information, in man-made colour codes and in naturally occurring colour codes that signal ripeness of fruit, freshness of meat or illness. They can be denied the benefit of colour to mark out objects and organise complex visual displays. They may be unreliable when a colour name is used as an identifier. They are slower and less successful in search when colour is an attribute of the target object or is used to organise the visual display. Because those with the more severe forms of abnormal colour vision perceive a very limited gamut of colours, they are at a disadvantage in the pursuit and appreciation of those forms of art that use colour.

Background With standardized examination conditions, a web-based color vision test using pseudoisochromatic color plates can deliver test results comparable to those yielded by conventional color vision tests. The aim of the study is to analyze to what extent a web-based color vision test can be used as a screening test on the internet after visual monitor calibration. Methods A German-language web-based color vision test with 25 pseudoisochromatic color plates based on the color plates of Velhagen and Broschmann and of Ishihara was developed, which can be seen at http://www.farbsehtest.de. Volunteers were recruited by means of specific information distributed on the internet, in various print media, and on the radio. Results Over a period of 12 months, 2,126 of the initial volunteers [541 women and 1,588 men; mean age 34.27 (±14.1) years] with a valid test result for 25 color plates performed the web-based color vision test, 1,700 (506 women and 1,194 men) of whom passed it. Of the 426 volunteers who did not pass the test, 32 were women and 394, men. Counter-testing was performed on 101 volunteers (34 women and 67 men) with a mean age of 36.74 (±11.6) years. Conclusions The results recorded in the patients who underwent counter-testing suggest that, if handled correctly, the web-based color vision test can be used as a color vision screening test on the internet.

Barry L Cole

Colour vision deficiency (CVD) has a high prevalence and is often a handicap in everyday life. Those who have CVD will be better able to adapt and make more informed career choices, if they know about their deficiency. The fact that from 20 to 30 per cent of adults with abnormal colour vision do not know they have CVD suggests that colour vision is not tested as often as it should be. This may be because of practitioner uncertainty about which tests to use, how to interpret them and the advice that should be given to patients on the basis of the results. The purpose of this paper is to recommend tests for primary care assessment of colour vision and provide guidance on the advice that can be given to patients with CVD. The literature on colour vision tests and the relationship between the results of the tests and performance at practical colour tasks was reviewed. The colour vision tests that are most suitable for primary care clinical practice are the Ishihara test, the Richmond HRR 4th edition 2002 test, the Medmont C-100 test and the Farnsworth D15 test. These tests are quick to administer, give clear results and are easy to interpret. Tables are provided summarising how these tests should be interpreted, the advice that can be given to CVD patients on basis of the test results, and the occupations in which CVD is a handicap. Optometrists should test the colour vision of all new patients with the Ishihara and Richmond HRR (2002) tests. Those shown to have CVD should be assessed with the Medmont C-100 test and the Farnsworth D15 test and given appropriate advice based on the test results.

Jennifer Birch

Screening sensitivity, based on a specific number of errors, of the Ishihara plates and of the American Optical Company (Hardy, Rand and Rittler) plates (HRR plates) was determined by reviewing data obtained for 486 male anomalous trichromats identified and classified with the Nagel anomaloscope. Data were obtained for the 16 screening plates, with Transformation and Vanishing numeral designs, of the 38 plate Ishihara test, and for the four red-green screening plates (with six Vanishing designs) of the HRR test. Sensitivity of the Ishihara plates was found to be 97.7% on 4 errors and 98.4% on 3 errors. Only anomalous trichromats with slight deficiency, according to the anomaloscope matching range, made 8 errors or fewer. One screening error, a single missed figure, is normally allowed as a pass on the HRR test and 3 errors is often recommended as the fail criterion to eliminate false positive results. Twenty-three subjects made no error on the HRR screening plates and 12 subjects made a single error (35 anomalous trichromats). Screening sensitivity was therefore 92.8% using 2 errors as the fail criterion. Screening sensitivity was reduced to 87% when 3 errors was the fail criterion, and some deuteranomalous trichromats with moderate deficiency, according to the anomaloscope matching range, were not identified. Individuals who make a maximum of 2 errors on the HRR test, or on the Richmond HRR 4th Edition, should be re-examined with the Ishihara plates to determine their colour vision status. The present review confirms that the Ishihara test is a very sensitive screening test and identifies people with slight anomalous trichromatism. The HRR test is unsatisfactory for screening and should not be chosen solely for this purpose.

Vivianne C. Smith
Joel Pokorny
Arlene S. Pass

Error scores on the Farnsworth-Munsell 100-hue test were partitioned into those representing red-green and those representing blue-yellow losses. Data from two groups of normal observers were used. One group showed results characteristic of published norms; one group showed superior performance. Both observers showed a correlation between red-green and blue-yellow scores indicative of a strong performance factor in this test. The difference between blue-yellow and red-green scores eliminates their correlated variance and allows evaluation of the axis. Both groups showed an increase in difference scores, with age indicating development of a blue-yellow axis. This increase was significant for the observers characteristic of the norms. We suggest cutoff scores to allow a decision as to whether a given patient shows a blue-yellow or red-green axis.

Source: https://www.researchgate.net/publication/301537391_Comparison_of_Ishihara_Booklet_with_Color_Vision_Smartphone_Applications

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