Table 1.
Definitions of test and performance characteristics
| Gold standard | ||||
|---|---|---|---|---|
| |
|
Yes |
No |
|
| |
Yes |
X |
Y |
|
| |
No |
Z |
K |
|
| |
|
|
|
|
| Test/Performance Characteristic |
|
Definition |
Explanation |
|
| Patient Classification, % |
|
|
|
|
| True-Positive |
|
X / (No. of Patients) × 100% |
|
|
| False-Positive |
|
Y / (No. of Patients) × 100% |
|
|
| True-Negative |
|
K / (No. of Patients) × 100% |
|
|
| False-Negative |
|
Z / (No. of Patients) × 100% |
|
|
| Sensitivity, % |
|
X / (X+Z) × 100% |
% of FN hospitalizations correctly identified by claims-based definition |
|
| Specificity, % |
|
K / (Y+K) × 100% |
% of non-FN hospitalizations correctly identified by claims-based definition |
|
| Positive Predictive Value (PPV), % |
|
X / (X+Y) × 100% |
% of hosp. identified as FN hosp. by claims-based definition that were true-positives |
|
| Negative Predictive Value (NPV), % |
|
K / (Z+K) × 100% |
% of hosp. identified as non-FN hosp. by claims-based definition that were true-negatives |
|
| Accuracy, % |
|
(X+K) / (No. of Patients) × 100% |
% of all hospitalizations that were true-positives and true-negatives |
|
| Likelihood ratio positive (LR+) |
|
[X/(X+Z)] / [1-K/(Y+K)] |
Odds of hosp. being an FN hosp. when claims-based algorithm is positive |
|
| Likelihood ratio negative (LR-) | [1-X/(X+Z)] / [K/(Y+K)] | Odds of hosp. being a non-FN hosp. when claims-based algorithm is negative | ||
FN: febrile neutropenia.