Table 6.
Relationship between non-combined surgery and type of surgery
| Combined surgery | Type of surgery
|
Total | |
|---|---|---|---|
| Shunt* (%) | Filter** (%) | ||
| Non-combined | 71 (64.0) | 40 (36.0) | 111 |
| Combined | 18 (39.1) | 28 (60.9) | 46 |
| Total | 89 (56.7) | 68 (43.3) | 157 |
| Chi-square test1 | |||
|
| |||
| Value | df | Asymptotic significance (2-sided) | |
|
| |||
| Pearson chi-square | 8.169a | 1 | 0.004 |
| Continuity correctionb | 7.189 | 1 | 0.007 |
| Likelihood ratio | 8.148 | 1 | 0.004 |
| Linear-by-linear association | 8.117 | 1 | 0.004 |
| N of valid cases | 157 | ||
| Symmetric measures2 | |||
|
| |||
| Value | P<0.05 | ||
|
| |||
| Phi | 0.228 | 0.004 | |
| Cramer’s V | 0.228 | 0.004 | |
| N of valid cases | 157 | ||
Notes:
*
Shunting surgery includes Baerveldt and Ahmed implants.
**
Filtering surgery includes trabeculectomy and Express.
a
0 cells (0.0%) have expected count <5. The minimum expected count is 19.92.
b
Computed only for a 2×2 table.
1
Chi-square test, statistical method assessing the relationship between observed and expected categorical values.
2
Symmetric measures determine strength of relationship between the observed and expected categorical values.