Table 3:

Accuracy parameters of case definitions in the British Columbia node of the Canadian Primary Care Sentinel Surveillance Network

DefinitionSensitivity (95% CI)Specificity (95% CI)PPV (95% CI)NPV (95% CI)
1.1. MaRNet-FP
1 ICD-9 code OR ACEI/ARB + BB + diuretic
90.3 (81.0–96.0)93.3 (89.4–96.1)80.2 (69.9–88.3)97.0 (93.8–98.8)
1.2. MaRNet-FP
Including billings
93.1 (84.5–97.7)90.8 (86.4–94.1)75.3 (65.0–83.8)97.7 (94.8–99.3)
Expanding codes and testing iterations and specific combinations (BC group 1)
2.1. One expanded code AND specific medication75.0 (63.4–84.5)92.9 (88.9–95.8)76.1 (64.5–85.4)92.5 (88.4–95.5)
2.2. One expanded code only91.7 (82.7–96.9)91.2 (86.9–94.5)75.9 (65.5–84.4)97.3 (94.4–99.0)
2.3. Two expanded codes83.3 (72.7–91.1)94.6 (90.9–97.1)82.2 (71.5–90.2)95.0 (91.4–97.4)
2.4. Specific medication only18.1 (10.0–91.1)99.6 (97.7,100.0)92.9 (66.1–99.8)80.1 (75.1–84.5)
2.5. (2.1. or 2.3. or 2.4)87.5 (77.6–94.1)92.1 (87.9–95.1)76.8 (66.2–85.4)96.1 (92.7–98.2)
Addition of furosemide (BC group 2)
3.1. (2.1. OR furosemide)80.6 (69.5–88.9)94.1 (90.4–96.8)80.6 (69.5–88.9)94.1 (90.4–96.8)
3.2. (3.1. including billing)90.3 (81.0–96.0)91.6 (87.4–94.8)76.5 (66.0–85.0)96.9 (93.7–98.7)
Including low-threshold NP
4.1. (1.1. OR low-threshold NP)93.1 (84.5–97.7)88.7 (84.0–92.4)71.3 (61.0–80.1)97.7 (94.7–99.2)
4.2. (1.2. OR low-threshold NP)94.4 (86.4–98.5)87.0 (82.1–91.0)68.7 (58.6–77.6)98.1 (95.2–99.5)
4.3. (3.2. OR low-threshold NP)93.1 (84.5–97.7)87.0 (82.1–91.0)68.4 (58.2–77.4)97.7 (94.6–99.2)
Including high-threshold NP
5.1. (1.1 OR high-threshold NP)91.7 (82.7–96.9)92.9 (88.9–95.8)79.5 (69.2–87.6)97.4 (94.4–99.0)
5.2. (1.2 OR high-threshold NP)93.1 (84.5–97.7)90.8 (86.4–94.1)75.3 (65.0–83.8)97.7 (94.8–99.3)
5.3. (3.2 OR high-threshold NP)90.3 (81.0–96.0)91.6 (87.4–94.8)76.5 (66.0–85.0)96.9 (93.7–98.7)
  • Note: ACEI = angiotensin-converting-enzyme inhibitor, ARB = angiotensin II receptor blocker, BB = β-blocker, BC = British Columbia, CI = confidence interval, MARNet-FP = Maritime Family Practice Research Network, NP = natriuretic peptide, NPV = negative predictive value, PPV = positive predictive value.