Regression model — mean absolute errora
| Estimate | 95% CI | P-value | |
|---|---|---|---|
| Intercept | 0.62 | 0.37 to 1.04 | 0.051 |
| Length of time in service | |||
| Years in service (each additional year) | 1.08 | 1.04 to 1.12 | <0.001 |
| Frequency of use | |||
| >10 times per month | 0.94 | 0.66 to 1.38 | 0.76 |
| 6–10 times per month | 0.82 | 0.61 to 1.12 | 0.19 |
| 1–5 times per month | 1 | reference | |
| 6–11 times per year | 0.90 | 0.68 to 1.20 | 0.47 |
| 1–5 times per year | 0.94 | 0.66 to 1.36 | 0.74 |
| Less frequently | 0.89 | 0.61 to 1.32 | 0.53 |
| Not known | 0.80 | 0.38 to 2.07 | 0.61 |
| Cost of device | |||
| Cost (every £1 increase) | 1.00 | 0.99 to 1.01 | 0.75 |
| Tested (reference: no) | |||
| Yes | 1.21 | 0.80 to 1.91 | 0.38 |
| Not known | 1.10 | 0.87 to 1.41 | 0.44 |
| Make (reference: Boots) | |||
| Lloyds | 1.31 | 0.90 to 1.90 | 0.13 |
| Omron | 1.01 | 0.75 to 1.37 | 0.94 |
| Other | 1.23 | 0.80 to 1.92 | 0.34 |
| Validation status (reference: not validated/not applicable) | |||
| Validated | 0.77 | 0.59 to 1.02 | 0.044 |
↵a The proportion in MAE change is the unit of predictor unless otherwise stated. MAE = mean absolute error.