Scoring system 2: LN-No Code
| Patient characteristic All patients are required to have at least one diagnosis code (ICD9 or ICD10) for SLE | Points (add unless stated) | Total score | Predicted probability |
| Highest urine protein–creatinine (UPCr) ratio test greater than or equal to 1 but less than 3 g/g Or Highest UPCr ratio test greater than or equal to 3 g/g | 25 | <35 | <50% |
| 30 | 35–55 | 50–60% | |
| One diagnosis code for acute or chronic kidney disease or proteinuria Or Two or more diagnosis codes for acute or chronic kidney disease or proteinuria | 50 | 55–70 | 60–70% |
| 80 | 70–90 | 70–80% | |
| One or more urinalysis tests positive for protein | 35 | 90–125 | 80–90% |
| Age (in years) at first SLE diagnosis code | Subtract age | >125 | >90% |
Diagnosis codes for LN included ICD10 codes: M32.14 or M32.15, or ICD9 code: 710.0 in combination with ICD9 codes: 583.81, 581.81 or 583.89. Diagnosis codes for acute or chronic kidney disease or proteinuria included ICD10 codes: N00–N08, N17–N19 and R80, or ICD9 codes: 580–586 and 791.0.
ICD, International Classification of Diseases; LN, lupus nephritis.