Table 2.
Mean absolute error compared with reference device, and failure rate of tested monitors (n = 327) by length of time in servicea
| Years in hservice | Monitors, n | Failing monitors, n (%)b | Cumulative failing monitors, n (%)c | MAE, mmHg (95% CI) |
|---|---|---|---|---|
| 0–1 | 41 | 0 | 0 | 0.63 (0.55 to 0.72) |
| >1–2 | 50 | 5 (10) | 5 (5) | 0.73 (0.66 to 0.81) |
| >2–3 | 36 | 1 (3) | 6 (5) | 0.62 (0.53 to 0.71) |
| >3–4 | 28 | 2 (7) | 8 (5) | 0.80 (0.70 to 0.90) |
| >4–5 | 29 | 6 (21) | 14 (8) | 1.03 (0.93 to 1.13) |
| >5–6 | 20 | 7 (35) | 21 (10) | 1.44 (1.32 to 1.56) |
| >6–7 | 14 | 2 (14) | 23 (11) | 0.88 (0.73 to 1.02) |
| >7–10 | 54 | 15 (28) | 38 (14) | 1.18 (1.10 to 1.25) |
| >10 | 7 | 2 (29) | 40 (14) | 1.29 (1.08 to 1.50) |
| Not stated/monitor owner unable to remember | 48 | 6 (13) | n/a | 0.89 (0.81 to 0.97) |
a
Four monitors could not be tested fully but should be counted as failures.
b
Percentage of total monitors per years-in-service classification.
c
Percentage of cumulative total of monitors per years-in-service classification and shorter lengths of service. MAE = mean absolute error.