Subject ratings of interventions and effects of interventions on company measures of productivity*
| Intervention | p Value† | ||||
|---|---|---|---|---|---|
| Ergonomic training only | Ergonomic training + trackball | Ergonomic training + armboard | Ergonomic training + trackball + armboard | ||
| (n = 46) | (n = 45) | (n = 46) | (n = 45) | ||
| *Subjects assessed their intervention at end of study or time of dropout. | |||||
| †ANOVA for continuous measures and χ2 for categorical measures. | |||||
| ‡Change in productivity is the difference between employer measured mean productivity during the year post-intervention and the year before the intervention. Only data from 162 subjects were available for these calculations. | |||||
| §% work time is the number of hours logged on and available for a call divided by the number of hours at work × 100. | |||||
| ¶Handle time is the time (seconds) it takes to completely process a call. | |||||
| Subjects’ evaluation of intervention | |||||
| Decreased pain | 5 | 14 | 29 | 20 | 0.001 |
| Increased pain | 1 | 4 | 1 | 4 | 0.27 |
| Liked or helped | 18 | 24 | 25 | 22 | 0.45 |
| Did not like | 2 | 1 | 1 | 1 | 0.90 |
| Difficult to use | 0 | 4 | 1 | 5 | 0.06 |
| Measured productivity changes‡ | |||||
| Change in % work time§ | −2.7 (10.3) | 0.04 (8.0) | −2.3 (8.7) | −2.8 (13.7) | 0.57 |
| Change in average handle time¶ | −25 (57) | −10 (51) | 4 (66) | −17 (96) | 0.30 |
| Change in calls per hour | 0.4 (1.3) | 0.6 (1.5) | 0.1 (1.7) | 0.2 (2.3) | 0.57 |
| Subjects reporting improved productivity | 18 | 27 | 30 | 27 | 0.31 |