Table 1.
Components and algorithm for 7 EHR phenotypes for diabetes
| Abbreviation | ICD_250 | CCW | A1c | Med | DDC | Sup-DM | NW | A1c_Med | |
|---|---|---|---|---|---|---|---|---|---|
| Full name | ICD-9 code 250.xx | Expanded ICD-9 codes | Abnormal A1c (≥ 6.5%) | DM Med | DDC | SUPREME DM | eMERGE NW | Abnormal A1c + DM Meda | |
| Based on | ICD-9 billing codes | Other DM codes HEDIS misses | NYC A1c h ealth department registry | PBM | Population Health Type 2 DM | Population Health Any DM | Exclusively Type 2 DM | A combination of abnormal A1c and PBM | |
| Components | |||||||||
| 1a | ICD-9 250.x0, 250.x2 | IP or AMB x1 | IP x1 or AMB x2 | (–) | (–) | IP, AMB, or ED x 1 | IP x1 or AMB x2 | IP, AMB, or ED x1 | (–) |
| 1b | ICD-9 250.x1, 250.x3 | IP or AMB x1 | IP x1 or AMB x2 | (–) | (–) | (–) | IP x1 or AMB x2 | (–) | (–) |
| 1c | ICD-9 249.xx | (–) | IP x1 or AMB x2 | (–) | (–) | IP, AMB, or ED x1 | (–) | (–) | (–) |
| 1d | ICD-9 other codes | (–) | IP x1 or AMB x2 | (–) | (–) | IP, AMB, or ED x1 | IP x1 or AMB x2 | (–) | (–) |
| 2a | Diabetes Med Group 1: insulin | (–) | (–) | (–) | 1 or more DM med on AMB med rec | 1 + AMB med rec | 1+ AMB med rec | Excludes any patient on insulin or amylin | 1 or more DM med on AMB med rec |
| 2b | Diabetes Med Group 2: insulin secretagogues and incretins | (–) | (–) | (–) | 1+ AMB med rec | 1+ AMB med rec | Must have type 2 code | ||
| 2c | Diabetes Med Group 3: thiazolidinediones and metformin | (–) | (–) | (–) | 1+ AMB med rec | Excludes if this is the only criteria met | |||
| 3 | Abnormal glucose lab | (–) | (–) | (–) | 2 abnormal labs in past 365 d | 2 abnormal labs in past 720 d | (–) | ||
| 3a | A1c ≥ 6.5% once | (–) | (–) | 1+ abnormal | (–) | 1+ abnormal | |||
| 3b | A1c ≥ 6.5 % twice | (–) | (–) | 1+ abnormal | (–) | 1+ abnormal | |||
| 3c | Fasting glucose ≥ 126 × 2 | (–) | (–) | (–) | (–) | (–) | |||
| 3d | Random glucose ≥ 200 × 2 | (–) | (–) | (–) | (–) | (–) | |||
| 3e | Abnormal OGTT | (–) | (–) | (–) | (–) | (–) | |||
| 3f | Two of above | (–) | (–) | (–) | (–) | (–) | |||
| Simplified algorithm | 1a or 1b | 1a or 1b or 1c or 1d | 3a | 2a or 2b or 2c | 1a or 1c or 1d or 2a or 2b or 2c or 3b or 3c or 3d or 3e or 3f | 1a or 1b or 1d or 2a or 2b or 3a or 3b or 3c or 3d or 3e or 3f | 1a but never 1b and never 2a unless controlled on oral agents | 3a or 2 | |
| No. patients identified by phenotype | 18 893 | 16 320 | 12 182 | 11 800 | 22 050 | 18 958 | 11 620 | 15 478 | |
| Extrapolated no. patients with type 2 DM knowing sensitivity/specificity that phenotype would identify | 13 906 | 12 804 | 10 507 | 9481 | 14 414 | 13 422 | 10 073 | 12 480 | |
| Extrapolated no. patients with any DM knowing sensitivity/specificity that phenotype would identify | 15 833 | 14 521 | 11 741 | 10 668 | 16 387 | 15 281 | 10 408 | 13 904 | |
| PPV type 2 DM | 0.74 | 0.78 | 0.87 | 0.80 | 0.66 | 0.71 | 0.86 | 0.81 | |
| PPV any DM | 0.84 | 0.89 | 0.97 | 0.91 | 0.75 | 0.81 | 0.89 | 0.90 | |
aThe eighth phenotype, A1c_Med, was a combination of phenotypes 3 (A1c) and 4 (Med) and was devised and studied after the sampling strategy.
AMB, ambulatory; DDC, Durham Diabetes Coalition; DM, diabetes mellitus; ED, emergency department; eMERGE NW, Electronic Medical Records and Genomics Network, Northwestern University; HEDIS, Healthcare Effectiveness Data and Information Set; ICD-9, International Classification of Diseases, Ninth Revision; IP, inpatient; med, medication; NYC, New York City; PBM, pharmacy benefit manager; OGTT, oral glucose tolerance test; PPV, positive predictive value; rec, reconciliation; SUPREME DM, Surveillance, Prevention, and Management of Diabetes Mellitus Project; T2, type 2.