Table 4.
Accuracy and Coverage of the Algorithm Designed to Detect Pulse Irregularities Attributable to AF According to the ECV and HOL Testing Data Set
| Testing Data Set | Epoch‐by‐Epoch Statistics | Episode Statistics | Duration Statistics | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Accuracy % (CI) | Sensitivity % (CI) | Specificity % (CI) | NPV % (CI) | PPV % (CI) | Coverage % (CI) | Sensitivity % (CI) | PPV % (CI) | Sensitivity % (CI) | PPV % (CI) | |
| ECV | ||||||||||
| Average | 98±4 (96–100) | 97±7 (91–100) | 100±1 (99–100) | 98±6 (93–100) | 99±4 (96–100) | 57±18 (46–68) | 98±6 (94–100) | 99±4 (96–100) | 98±7 (93–100) | 94±13 (86–99) |
| Gross | 98 | 96 | 100 | 98 | 100 | 47 | 99 | 99 | 96 | 98 |
| HOL | ||||||||||
| Average | 97±10 (92–100) | 93±14 (82–100) | 100±0 (100–100) | n.a. | n.a. | 52±12 (47–57) | 95±11 (85–99) | n.a. | 93±14 (81–99) | n.a. |
| Gross | 97 | 93 | 100 | 95 | 100 | 48 | 95 | 100 | 93 | 100 |
Sensitivity and PPV for episode and duration statistics are defined according to the Association for the Advancement of Medical Instrumentation standards. AF indicates atrial fibrillation; CI, 95% confidence interval of the mean as obtained by bootstrapping and resampling of the test data set (100 iterations); ECV, cardioversion cohort of patients; Average, indicates accuracy described by mean (± SD deviation) of the value across patients; Gross, accuracy determined by aggregating results from each patient into one; HOL, Holter cohort of patients; NPV, negative predictive value; PPV, positive predictive value; n.a., not available. NPV and PPV could not be defined as average accuracy in epoch‐by‐epoch statistics because patients showed either AF or non‐AF in the reference annotations in the HOL cohort.