Table 2.
Reliability analysis of Chinese version of Glaucoma Quality of Life-15 item Questionnaire (GQL-15-CHI)
| Subscale and item | Item-total scale correlation | Item-subscale correlation | Cronbach α | Intraclass correlation coefficient |
Ceiling n (%) |
Floor n (%) |
|---|---|---|---|---|---|---|
| Central and near vision |
|
|
0.75 |
0.73 (0.65-0.79). |
158 (31.10) |
11 (2.17) |
| Recognizing faces |
0.64 |
0.58 |
|
|
|
|
| Reading newspapers |
0.69 |
0.58 |
|
|
|
|
| Peripheral vision |
|
|
0.91 |
0.91 (0.90-0.92) |
143 (28.15) |
3 (0.59) |
| Seeing objects coming from the side |
0.61 |
0.61 |
|
|
|
|
| Walking on uneven ground |
0.78 |
0.74 |
|
|
|
|
| Tripping over objects |
0.69 |
0.72 |
|
|
|
|
| Judging distance of foot to step |
0.63 |
0.65 |
|
|
|
|
| Walking on steps/stairs |
0.76 |
0.74 |
|
|
|
|
| Bumping into objects |
0.69 |
0.73 |
|
|
|
|
| Glare and dark adaptation |
|
|
0.90 |
0.90 (0.88-0.91) |
54 (10.63) |
1 (0.20) |
| Walking after dark |
0.81 |
0.80 |
|
|
|
|
| Seeing at night |
0.78 |
0.77 |
|
|
|
|
| Adjusting to dim light |
0.69 |
0.70 |
|
|
|
|
| Adjusting to bright light (glare) |
0.56 |
0.54 |
|
|
|
|
| Going from light to dark room or vice versa |
0.72 |
0.73 |
|
|
|
|
| Finding dropped objects |
0.77 |
0.70 |
|
|
|
|
| Outdoor mobility |
|
|
NA |
NA |
249 (49.01) |
15 (2.95) |
| Crossing the road | 0.77 | 1.00 |
NA: not available for only one-item subscale.