Table
4: Binocular
visual acuity (BVA) and binocular summation (BS) of BVA in the group B with
prismatic and non-prismatic correction after the entry examination and after
30-day trial wearing. The bold marked pairs (prism vs. non-prism) vary at
statistically significant level p < 0.05 (column „Wilcoxon test results).
Number behind BVA and BS signs the Weber’s contrast level; total = sum of ETDRS
letters, correctly read at all contrast levels.
|
Group B. binocular visual
acuity (BVA) and summation (BS) |
|||||||
|
After examination |
Mean
values | Standard deviations |
Wilcoxon
test results (p) |
|||||
|
At a
distance (number of
ETDRS letters) |
Prism |
Non-prism |
Difference |
||||
|
BVA (full contrast) |
87.765 |
5.007 |
88.235 |
5.032 |
-0.471 |
2.154 |
0.551 |
|
BVA (50% contrast) |
85.471 |
5.467 |
85.647 |
5.279 |
-0.176 |
2.215 |
0.975 |
|
BVA (25% contrast) |
81.118 |
6.781 |
82.118 |
6.698 |
-1.000 |
1.871 |
0.033 |
|
BVA (10% contrast) |
70.941 |
9.236 |
71.471 |
9.008 |
-0.529 |
2.503 |
0.594 |
|
BVA (sum of all contrast levels) |
325.294 |
25.201 |
327.471 |
24.925 |
-2.176 |
5.318 |
0.124 |
|
BS (full contrast) |
1.353 |
2.317 |
1.824 |
2.921 |
-0.471 |
2.154 |
0.551 |
|
BS (50% contrast) |
0.824 |
2.834 |
1.000 |
2.574 |
-0.176 |
2.215 |
0.975 |
|
BS (25% contrast) |
0.647 |
2.827 |
1.647 |
3.061 |
-1.000 |
1.871 |
0.033 |
|
BS (10% contrast) |
2.471 |
3.939 |
3.000 |
4.690 |
-0.529 |
2.503 |
0.594 |
|
BS (sum of all contrast levels) |
5.294 |
8.651 |
7.471 |
10.180 |
-2.176 |
5.318 |
0.124 |
|
At near distances (decimal) |
|
|
|
|
|
|
|
|
BVA |
0.994 |
0.024 |
0.982 |
0.039 |
0.012 |
0.033 |
0.180 |
|
BS |
0.006 |
0.025 |
-0.006 |
0.043 |
0.012 |
0.034 |
0.180 |
|
After 30-day trial wearing |
Mean values | Standard deviations |
Wilcoxon test results (p) |
|||||
|
At a distance (number of ETDRS letters) |
Prism |
Non-prism |
Difference |
||||
|
BVA (full contrast) |
88.588 |
4.273 |
89.000 |
5.050 |
-0.412 |
3.312 |
0.496 |
|
BVA (50% contrast) |
86.941 |
5.761 |
87.059 |
5.651 |
-0.118 |
4.732 |
0.724 |
|
BVA (25% contrast) |
82.647 |
6.294 |
83.412 |
5.280 |
-0.765 |
3.955 |
0.433 |
|
BVA (10% contrast) |
72.235 |
8.066 |
72.647 |
8.208 |
-0.412 |
6.006 |
0.660 |
|
BVA (sum of all contrast levels) |
330.412 |
23.262 |
332.118 |
23.358 |
-1.706 |
13.143 |
0.670 |
|
BS (full contrast) |
0.706 |
1.312 |
1.647 |
2.422 |
-0.941 |
2.703 |
0.187 |
|
BS (50% contrast) |
1.176 |
2.298 |
1.235 |
2.611 |
-0.059 |
3.363 |
0.969 |
|
BS (25% contrast) |
0.471 |
2.695 |
1.882 |
3.039 |
-1.412 |
3.743 |
0.060 |
|
BS (10% contrast) |
1.941 |
3.288 |
2.941 |
3.211 |
-1.000 |
3.279 |
0.196 |
|
BS (sum of all contrast levels) |
4.294 |
5.497 |
7.824 |
6.849 |
-3.529 |
6.539 |
0.041 |
|
At near distances (decimal) |
|
|
|
|
|
|
|
|
BVA |
0.994 |
0.024 |
0.988 |
0.049 |
0.006 |
0.072 |
0.655 |
|
BS |
0.006 |
0.024 |
0.000 |
0.000 |
0.006 |
0.024 |
- |