Table 3.

Stage of Chronic Kidney Disease. Percent of study population at each institution identified with CKD stages 3A, 3B, and 4 based on laboratory results alone, without a documented ICD-10 diagnosis or HCC code (see Table 2, row 1). Stage 3A, eGFR between 45 to 59 ml/min/1.73m2 for 3 months or more; Stage 3B, eGFR between 30 to 45 ml/min/1.73m2 for 3 months or more; Stage 4, eGFR between 15 to 29 ml/min/1.73m2 for 3 months or more. For each institution, absolute numbers of patients in each category are shown in the numerator in each parentheses; the total number of patients with CKD Stage 3 or Stage 4 by eGFR but with no corresponding ICD-10 or HCC code in the electronic medical record is shown as the denominator)

CKD Stage by eGFR but with no ICD-10 or HCC code	Institution A	Institution B	Institution C
3A	61% (7,612/12,478)	58% (282/487)	71% (13,797/19,433)
3B	26% (3,244/12,478)	31% (151/487)	22% (4,081/19,433)
4	13% (1,622/12,478)	11% (54/487)	7% (1,555/19,433)