Table 2.
Recalculated or Correct SMDs and SEs for the 6-month Follow-up Data in Walters et al. (2009)
| N | Mean | SD | SMD | SE | g | SE | |
|---|---|---|---|---|---|---|---|
| Drinks per week | |||||||
| MIF | 67 | 10.19 | 8.71 | ||||
| FBO | 54 | 12.07 | 12.31 | -0.18 | 0.18 | -0.18 | 0.18 |
| MIO | 59 | 11.59 | 9.55 | ||||
| AO | 61 | 12.92 | 14.16 | -0.11 | 0.18 | -0.11 | 0.18 |
| Alcohol-related problems | |||||||
| MIF | 66 | 4.06 | 4.96 | ||||
| FBO | 54 | 3.72 | 4.70 | 0.07 | 0.18 | 0.07 | 0.18 |
| MIO | 59 | 5.41 | 7.28 | ||||
| AO | 61 | 5.77 | 6.11 | -0.05 | 0.18 | -0.05 | 0.18 |
Note. MIF = Motivational interviewing with feedback; FBO = Feedback only; MIO = motivational interviewing only; AO = Assessment only. SMD = Standardized mean difference; SE = Standard error; g = Hedge's g. The underlined numbers indicate errors in Foxcroft et al. (2014) that reported SMD (SE) = 0.07 (0.18) and -0.05 (0.18) for drinks-per-week outcome data. N = 66 for alcohol-related problems for MIF was incorrectly reported as 67 in Foxcroft et al. Means and standard deviations were not reported in Foxcroft et al. but were obtained directly from Table 1 in Walters et al. (2009).