Table 4

Contribution of variables to the appropriateness scoring, by chapter.
Variable by Category
 Lineal Regression
 Logistic Regression


R2
 Difference
 P Value
 -2 log L
 Difference
 P Value
Simple Cataract


210.63

     Visual Acuity
 0.491
 -
 <0.001
 160.99
 49.64
 <0.001
     Visual Function
 0.788
 0.297
 <0.001
 117.08
 43.91
 <0.001
     Surgery Complexity
 0.901
 0.113
 <0.001
 96.41
 20.67
 0.0003
     Type of Cataract
 0.902
 0.001
 0.23
 94.60
 1.81
 0.185
     Contralateral Visual Acuity
 0.902
 0
 0.61
 88.36
 6.24
 0.06
Cataract with Diabetic Retinopathy


372.48

     Visual Function
 0.335
 -
 <0.001
 321.29
 51.19
 <0.001
     Expected Visual Acuity
 0.487
 0.152
 <0.001
 263.31
 57.98
 0.006
     Visual Acuity
 0.887
 0.4
 <0.001
 112.94
 150.37
 <0.001
     Surgery Complexity
 0.913
 0.026
 <0.001
 92.65
 20.29
 0.005
     Contralateral Visual Acuity
 0.916
 0.003
 0.006
 83.08
 9.57
 0.02
     Laterality of Cataract
 0.916
 0
 0.49
 83.02
 0.06
 0.8
Cataract with Other Pathologies


345.24

     Visual Function
 0.397
 -
 <0.001
 260.89
 84.35
 <0.001
     Anticipated Visual Acuity
 0.554
 0.157
 <0.001
 212.11
 48.78
 0.03
     Visual Acuity
 0.899
 0.345
 <0.001
 79.60
 132.51
 <0.001
     Surgery Complexity
 0.913
 0.014
 <0.001
 45.12
 34.48
 0.004
     Contralateral Visual Acuity
 0.914
 0.001
 0.1
 43.84
 1.28
 0.55
     Laterality of Cataract
 0.914
 0
 0.65
 41.85
 1.99
 0.17

R2: R Square. Difference: difference in R square after the introduction of the new variable

Ma Quintana et al. BMC Health Services Research 2006 6:23   doi:10.1186/1472-6963-6-23