Table 4 Score Distribution and Internal Consistency Characteristics of TSS-IOP Scales (n = 250)
TSS-IOP Scales | Mean (SD) Statistic | Number of Items | Chronbach's Alpha | Skewness Statistic | % Ceiling | Test-Retest Reliability (ICC's) |
|---|---|---|---|---|---|---|
Hyperemia | 91.3 (17.7) | 3 | .84 | -2.89 | 65.3% | .86 |
Eye Irritation | 91.2 (14.3) | 4 | .80 | -2.71 | 48.4% | .71 |
Convenience of Use | 80.2 (15.4) | 3 | .86 | -.53 | 20.8% | .78 |
Ease of Use | 68.9 (21.0) | 3 | .86 | -.58 | 10.8% | .86 |
Effectiveness | 77.0 (16.7) | 2 | .83 | -.95 | 14.9% | .41 |