Table 2.
Adjusted absolute and relative effect of the answer sheet on application time, and on over-reporting of drug use, inconsistencies and item nonresponse.
| On Booklet | On Answer Sheet | |||
|---|---|---|---|---|
|
| ||||
| Mean1 (95%CI) | Mean1 (95%CI) | Diff.1 (IC95%) | % of change1 (IC95%) | |
| Completion Time (minutes)2 | 35.36 (33.66 – 37.07) | 52.98 (50.25 – 55.70) | 17.61 (14.40 – 20.83) | 49.9 (39.6 – 60.9) |
| Extreme reports of drug use (%)3 | 0.36 (0.02 – 0.70) | 0.80 (0.32 – 1.28) | 0.44 (−0.15 – 1.03) | 125.8 (−26.8 – 596.7) |
| Inconsistent reports (No.)4 | 2.00 (1.72 – 2.27) | 3.52 (2.93 – 4.11) | 1.52 (0.91 – 2.14) | 93.0 (57.2 – 136.9) |
| Item nonresponse (No.)4 | 3.37 (2.77 – 3.97) | 2.25 (1.77 – 2.74) | −1.12 (−1.87 – −0.37) | −31.3 (−48.0 – −9.3) |
Diff: Absolute difference between Answer Sheet and Booklet.
1
Adjusted by gender and ethnic background;
2
Estimated with a generalized linear models specifying a normal distribution and Identity/Log link function
3
Estimated with a generalized linear models specifying a binomial distribution and Identity/Log link function.
4
Estimated with a generalized linear models specifying a negative binomial distribution and Identity/Log link function.