Direct observation for the evaluation of pursuits suffers from the same shortcomings as direct observation for saccades. Although the technique is rather easy to teach to an inexperienced clinician, the observations that must be made are more difficult to teach.
Another testing format that has been available for some time is Groffman tracings (93). Unfortunately, there has been no research to demonstrate either the validity or reliability of this test.
TABLE 1.13 NSUCO Pursuit Test Minimal Acceptable Score by Age and Sex (>1 standard deviation from mean)
| Ability | Accuracy | Head Movement | Body Movement | |||||
| Age | Male | Female | Male | Female | Male | Female | Male | Female |
| 5 | 4 | 5 | 2 | 3 | 2 | 3 | 3 | 4 |
| 6 | 4 | 5 | 2 | 3 | 2 | 3 | 3 | 4 |
| 7 | 5 | 5 | 3 | 3 | 3 | 3 | 3 | 4 |
| 8 | 5 | 5 | 3 | 3 | 3 | 3 | 4 | 4 |
| 9 | 5 | 5 | 3 | 4 | 3 | 3 | 4 | 4 |
| 10 | 5 | 5 | 4 | 4 | 4 | 4 | 4 | 5 |
| 11 | 5 | 5 | 4 | 4 | 4 | 4 | 4 | 5 |
| 12 | 5 | 5 | 4 | 4 | 4 | 4 | 5 | 5 |
| 13 | 5 | 5 | 4 | 4 | 4 | 4 | 5 | 5 |
| 14 or > | 5 | 5 | 5 | 4 | 4 | 4 | 5 | 5 |
Expected Values
Refer to Table 1.13 for expected findings.
Summary
We have emphasized the important general issues that must be considered when assessing accommodative, ocular motor, and binocular vision skills. We have also provided a recommended sequence of testing for all three areas, along with expected findings. A comprehensive assessment of these areas can be accomplished in a short period of time using very simple equipment. Given the high prevalence of accommodative, ocular motor, and binocular vision disorders in the general population, it is critical for clinicians to incorporate a battery of tests that can adequately assess these areas.
Study Questions
1. What are the advantages of the cover test compared to the von Graefe phoria?
2. Name two methods that tend to increase the validity and reliability of cover testing.
3. What are the advantages of the step vergence compared to the vergences measured in the phoropter?
4. How can you increase the reliability and repeatability of vergence testing?
5. Explain the importance of vergence facility testing. How is vergence facility testing different from step vergence or smooth vergence testing?
6. Why are smooth and step vergences alone an incomplete assessment of fusional vergence?
7. Describe two modifications to the NPC test that make it more sensitive.
8. Why is accommodative amplitude testing alone an incomplete assessment of accommodation?
9. What are the three aspects of accommodation that should be evaluated?
10. How can you increase the reliability and validity of accommodative amplitude testing in children?
11. What is the appropriate testing distance and target for the various binocular vision and accommodative tests discussed in the text?
12. What is the maximum amount of plus you can add during NRA testing? Why did you choose this value?
13. At what level should you stop the PRA test? Why did you choose this value?
Source of Equipment
(a) Synthetic Optics: 747 Butternut Drive, Franklin Lakes, NJ 07417.
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