Table 4.

Clinical score predicting the probability of obtaining a diagnosis

Variable	β-coefficient
Intercept	−0.622792
Age (in years)
If current CKD stage I or II	−0.052247
If current CKD stage III, IV, or V	−0.041056
First-degree history of kidney disease	1.346556
Current diagnosis on the basis of clinical presentation
Vascular disease	0
Glomerular disease	0.398665
Tubulo-interstitial disease	0.900757
Undiagnosed/isolated hematuria or proteinuria/other disease	0.389117
Developmental disorders/nonclassic cystic disease	1.753048

For a given patient, score value is equal to the sum of each predictor (β-coefficients x variable) + intercept. Estimated probability is then equal to 1/(1+e^-score).

For instance, for a 23-year-old patient with a CKD stage III, with no first-degree history of kidney disease, presenting with a tubulo-interstitial disease, the score value is: −0.622792 + 23 x (−0.041056) + 0.900757 = −0.666323. The probability of obtaining a diagnosis is then equal to 1/(1+e−⁽−^0.666323)) = 33.9%.