Table 4:

Final Generalized Estimating Equations Model to Predict CDVA

			beta 95% CI				Variable range		Effect over range
Independent Variables	Change	beta	low	high	p - value		minimum	maximum	Effect over range
Age	5 year increase	0.026	0.014	0.037	<0.001	^***	35	91	0.29
CD 0–2 mm	3 unit increase	0.022	0.011	0.034	<0.001	^***	17.3	48	0.23
Guttae Severity	1 unit increase	0.024	0.000	0.047	0.046	^*	0.5	4	0.08
Cataract Grade	1 unit increase	0.050	0.029	0.070	<0.001	^***	0	4	0.20
Corneal Edema	1 unit increase	0.117	0.063	0.172	<0.001	^***	0	3	0.35
Refraction Group	Hyperopia to myopia	0.061	0.016	0.106	0.008	^**	hyperopia	myopia	0.06
Refraction Group	No refractive error to hyperopia	−0.026	−0.071	0.019	0.256		N/A – effect not significant N/A – effect not significant
Refraction Group	No refractive error to myopia	0.035	−0.006	0.076	0.097	^†	N/A – effect not significant N/A – effect not significant
Intercept		0.172	0.137	0.207	<0.001	^***
Total effect, over the ranges, of all statistically significant variables:									1.21

p < 0.05,

^**

p < 0.01,

^***

p < 0.001,

^†

p < 0.15 (marginally significant).

CCD = central corneal densitometry; CDVA = corrected distance visual acuity; CI = confidence interval; hyperopia = refractive error GT plus 0.5; LogMAR = logarithm of the minimum angle of resolution; mm = millimeters; myopia = refractive error LT minus 0.5; N/A = not applicable; No refractive error = refractive error between −0.5 to +0.5; TOTAL = Total effect from all the “better” categories to all the “worse” (bolded) categories; NOTE: All Refraction Group effects must remain in the model as long as any of the effects are statistically significant.