Table 2. Impact of Real Cost Advertisements vs Control Videos on Trial Outcomesa.
| Measure | Vaping outcomes | Smoking outcomes | ||||||
|---|---|---|---|---|---|---|---|---|
| Mean (SD) | Difference between groups | Mean (SD) | Difference between groups | |||||
| Both Real Cost groups | Control group | b (95% CI) | P value | Both Real Cost groups | Control group | b (95% CI) | P value | |
| Susceptibility | ||||||||
| Visit 1 | 2.38 (0.96) | 2.75 (0.94) | −0.37 (−0.47 to −0.26) | <.001 | 2.27 (1.02) | 2.48 (1.00) | −0.21 (−0.33 to −0.11) | <.001 |
| Visit 2 | 2.58 (0.96) | 2.70 (0.97) | −0.15 (−0.26 to −0.04) | .008 | 2.37 (1.03) | 2.46 (1.01) | −0.13 (−0.24 to −0.01) | .03 |
| Visit 3 | 2.39 (0.99) | 2.57 (1.02) | −0.20 (−0.31 to −0.09) | <.001 | 2.19 (1.02) | 2.33 (1.03) | −0.17 (−0.28 to −0.05) | .005 |
| Visit 4 | 2.18 (1.03) | 2.36 (1.07) | −0.21 (−0.32 to −0.10) | <.001 | 2.04 (1.02) | 2.21 (1.05) | −0.21 (−0.32 to −0.10) | <.001 |
| Attention | ||||||||
| Visit 1 | 4.36 (0.85) | 3.91 (1.18) | 0.44 (0.34 to 0.54) | <.001 | NA | NA | NA | NA |
| Visit 2 | 4.44 (0.83) | 4.03 (1.11) | 0.44 (0.33 to 0.54) | <.001 | NA | NA | NA | NA |
| Visit 3 | 4.49 (0.78) | 4.10 (1.11) | 0.43 (0.33 to 0.54) | <.001 | NA | NA | NA | NA |
| Negative affect | ||||||||
| Visit 1 | 3.14 (1.09) | 2.47 (1.21) | 0.67 (0.54 to 0.80) | <.001 | NA | NA | NA | NA |
| Visit 2 | 3.22 (1.16) | 2.62 (1.31) | 0.59 (0.46 to 0.72) | <.001 | NA | NA | NA | NA |
| Visit 3 | 3.31 (1.16) | 2.68 (1.33) | 0.63 (0.50 to 0.76) | <.001 | NA | NA | NA | NA |
| Cognitive elaboration | ||||||||
| Visit 1 | 3.09 (1.24) | 2.90 (1.25) | 0.20 (0.07 to 0.33) | .002 | NA | NA | NA | NA |
| Visit 2 | 3.27 (1.17) | 3.20 (1.23) | 0.07 (−0.07 to 0.20) | .34 | NA | NA | NA | NA |
| Visit 3 | 3.47 (1.14) | 3.35 (1.18) | 0.10 (−0.03 to 0.24) | .08 | NA | NA | NA | NA |
| Visit 4 | 3.58 (1.20) | 3.43 (1.28) | 0.13 (−0.01 to 0.26) | .06 | NA | NA | NA | NA |
| Social interactions | ||||||||
| Visit 1 | 2.74 (1.38) | 2.65 (1.36) | 0.09 (−0.06 to 0.23) | .25 | NA | NA | NA | NA |
| Visit 2 | 2.96 (1.34) | 2.97 (1.35) | −0.01 (−0.16 to 0.14) | .86 | NA | NA | NA | NA |
| Visit 3 | 3.17 (1.30) | 3.03 (1.36) | 0.13 (−0.02 to 0.29) | .08 | NA | NA | NA | NA |
| Visit 4 | 3.27 (1.38) | 3.19 (1.45) | 0.08 (−0.07 to 0.23) | .28 | NA | NA | NA | NA |
| Health harm risk beliefs | ||||||||
| Visit 1 | 4.02 (1.00) | 3.54 (1.19) | 0.48 (0.36 to 0.60) | <.001 | 3.94 (1.21) | 3.66 (1.32) | 0.28 (0.14 to 0.41) | <.001 |
| Visit 2 | 3.84 (1.08) | 3.69 (1.18) | 0.16 (0.04 to 0.28) | .01 | 3.80 (1.27) | 3.72 (1.28) | 0.09 (−0.05 to 0.23) | .21 |
| Visit 3 | 3.99 (1.08) | 3.80 (1.17) | 0.19 (0.07 to 0.31) | .002 | 3.87 (1.28) | 3.78 (1.27) | 0.07 (−0.07 to 0.22) | .31 |
| Visit 4 | 4.09 (1.05) | 3.85 (1.18) | 0.25 (0.13 to 0.37) | <.001 | 4.00 (1.25) | 3.83 (1.29) | 0.17 (0.03 to 0.31) | .01 |
| Addiction risk beliefs | ||||||||
| Visit 1 | 3.70 (1.15) | 3.41 (1.15) | 0.28 (0.16 to 0.41) | <.001 | 3.77 (1.27) | 3.53 (1.38) | 0.23 (0.09 to 0.37) | .001 |
| Visit 2 | 3.63 (1.13) | 3.55 (1.16) | 0.09 (−0.04 to 0.22) | .19 | 3.67 (1.31) | 3.63 (1.36) | 0.03 (−0.12 to 0.18) | .68 |
| Visit 3 | 3.68 (1.15) | 3.52 (1.22) | 0.15 (0.02 to 0.28) | .02 | 3.75 (1.31) | 3.68 (1.30) | 0.05 (−0.10 to 0.20) | .53 |
| Visit 4 | 3.78 (1.15) | 3.58 (1.28) | 0.21 (0.08 to 0.34) | .006 | 3.81 (1.33) | 3.76 (1.37) | 0.05 (−0.10 to 0.20) | .50 |
| Attitudes | ||||||||
| Visit 1 | 2.54 (1.16) | 3.00 (1.17) | −0.46 (−0.59 to −0.33) | <.001 | 2.35 (1.38) | 2.56 (1.35) | −0.20 (−0.35 to −0.05) | .01 |
| Visit 2 | 2.80 (1.21) | 2.99 (1.23) | −0.21 (−0.35 to −0.08) | .002 | 2.53 (1.46) | 2.58 (1.44) | −0.10 (−0.25 to 0.06) | .22 |
| Visit 3 | 2.57 (1.27) | 2.78 (1.29) | −0.22 (−0.36 to −0.09) | .001 | 2.33 (1.43) | 2.52 (1.45) | −0.22 (−0.38 to −0.06) | .01 |
| Visit 4 | 2.36 (1.27) | 2.60 (1.33) | −0.27 (−0.40 to −0.14) | <.001 | 2.14 (1.40) | 2.35 (1.46) | −0.23 (−0.39 to −0.08) | .003 |
| Days used in the past week | ||||||||
| Visit 1 | 2.92 (1.81) | 2.95 (1.88) | 0.93 (0.78 to 1.10) | .40 | 2.86 (1.85) | 2.78 (1.80) | 0.90 (0.74 to 1.10) | .30 |
| Visit 2 | 2.32 (2.15) | 2.38 (2.18) | 0.89 (0.74 to 1.05) | .27 | 1.97 (2.03) | 2.01 (2.03) | 0.86 (0.71 to 1.05) | .14 |
| Visit 3 | 2.18 (2.19) | 2.31 (2.15) | 0.86 (0.72 to 1.03) | .09 | 1.82 (1.99) | 1.90 (1.99) | 0.84 (0.69 to 1.03) | .51 |
| Visit 4 | 1.92 (2.14) | 2.14 (2.11) | 0.82 (0.69 to 0.98) | .03 | 1.62 (1.97) | 1.80 (1.96) | 0.80 (0.65 to 0.97) | .03 |
Abbreviation: NA, not appliable.
a
Results are from linear mixed models, including unstandardized regression coefficients (b). Because days used in the past week had a Poisson-distributed count outcome, analyses used a log link function; these coefficients have been exponentiated and reflect multiplicative effects of trial group.