Table 1.
Positive Predictive Value of Individual Case Definition for Identifying Cases of Cerebral Venous Sinus Thrombosis
| Case Definitions (ICD-10-CM Codes) | TP, n | FP, n | PPV, % (95% CI) |
|---|---|---|---|
| G08: Intracranial and intraspinal phlebitis and thrombophlebitis | |||
| G08 as primary diagnosis | 11 | 1 | 91.7 (61.5–99.8) |
| G08 as primary or secondary diagnosis | 33 | 4 | 89.2 (75.6–97.0) |
| G08 as primary, secondary, or tertiary diagnosis | 43 | 5 | 89.6 (77.3–96.5) |
| G08 in any field of diagnosis | 60 | 8 | 88.2 (78.1–94.8) |
| I629: Nontraumatic intracranial hemorrhage, unspecified | |||
| I629 as primary diagnosis | 1 | 74 | 1.3 (0.0–7.2) |
| I629 as primary or secondary diagnosis | 4 | 125 | 3.1 (0.9–7.8) |
| I629 as primary, secondary, or tertiary diagnosis | 4 | 155 | 2.5 (0.7–6.3) |
| I629 in any field of diagnosis | 4 | 197 | 2.0 (0.5–5.0) |
| I636: Cerebral infarction due to cerebral venous thrombosis, non-pyogenic | |||
| I636 as primary diagnosis | 11 | 0 | 100.0 (71.5–100.0) |
| I636 as primary or secondary diagnosis | 14 | 0 | 100.0 (76.8–100.0) |
| I636 as primary, secondary, or tertiary diagnosis | 14 | 0 | 100.0 (76.8–100.0) |
| I636 in any field of diagnosis | 15 | 0 | 100.0 (78.2–100.0) |
| I676: Non-pyogenic thrombosis of intracranial venous system | |||
| I676 as primary diagnosis | 48 | 3 | 94.1 (83.8–98.8) |
| I676 as primary or secondary diagnosis | 70 | 7 | 90.9 (82.2–96.3) |
| I676 as primary, secondary, or tertiary diagnosis | 84 | 8 | 91.3 (83.6–96.2) |
| I676 in any field of diagnosis | 94 | 9 | 91.3 (84.1–95.9) |
Abbreviations: TP, true positive; FP, false positive; ICD-10-CM, International Classification of Diseases, 10th Revision, Clinical Modification; PPV, positive predictive value; CI, confidence interval.