Table 3. Regression Results for Mediation of Anxiety Sensitivity on Analogue Lapse Behavior Outcomes by Nicotine Withdrawal and Smoking Urges.
| Model | Path | b | SE | t | p | CI (l) | CI (u) | |
|---|---|---|---|---|---|---|---|---|
| Y1, M1 | ASI → MNWS (a) | .013 | .005 | 2.495 | .013 | .003 | .023 | |
| MNWS → DELAY (b) | -3.661 | 1.391 | -2.632 | .009 | -6.401 | -.922 | ||
| ASI → DELAY (c′) | -.002 | .113 | -.019 | .985 | -.225 | .221 | ||
| ASI → DELAY (c) | -.049 | .113 | -.429 | .669 | -.272 | .174 | ||
| ASI → MNWS → DELAY (a*b) | -.046 | .027 | -.126 | -.006 | ||||
|
| ||||||||
| Y1, M2 | ASI → QSU-T (a) | .015 | .005 | 3.016 | .003 | .005 | .025 | |
| QSU-T → DELAY (b) | -4.715 | 1.404 | -3.357 | .001 | -7.481 | -1.949 | ||
| ASI → DELAY (c′) | -.011 | .113 | -.095 | .924 | -.233 | .212 | ||
| ASI → DELAY (c) | -.082 | .113 | -.721 | .471 | -.304 | .141 | ||
| ASI → QSU-T → DELAY (a*b) | -.071 | .032 | -.150 | -.022 | ||||
| Model | Path | b | SE | z | p | CI (l) | CI (u) | |
|---|---|---|---|---|---|---|---|---|
| Y2, M1 | MNWS → CIG (b) | .135 | .139 | .970 | .332 | -.138 | .408 | |
| ASI → CIG (c′) | .002 | .011 | .152 | .880 | -.021 | .024 | ||
| ASI → CIG (c) | .003 | .011 | .304 | .761 | -.019 | .025 | ||
| ASI → MNWS → CIG (a*b) | .002 | .002 | -.001 | .008 | ||||
|
| ||||||||
| Y2, M2 | QSU-T → CIG (b) | .227 | .146 | 1.55 | .122 | -.060 | .514 | |
| ASI → CIG (c′) | .001 | .011 | .004 | .999 | -.022 | .022 | ||
| ASI → CIG (c) | .004 | .011 | .314 | .754 | -.018 | .025 | ||
| ASI → QSU-T → CIG (a*b) | .003 | .003 | -.001 | .011 | ||||
Note. N = 258 in all models. In a simple mediation model, the impact of X on Y is considered a total effect (path c), interpreted as the expected amount by which two cases that differ by one unit on X are expected to differ on Y, which may occur directly or indirectly. The direct effect of X (path c′) is interpreted as the part of the effect of X on Y that is independent of the pathway through M. The indirect effect (product of path a and b) is interpreted as the amount by which two cases who differ by one unit on X are expected to differ on Y through X′s effect on M, which in turn affects Y. This is the test of mediation (the effect of X on Y through M) or the difference between the total and direct effects (a*b = c – c′). The statistical strategy utilized here (as recommended by Hayes, 2009; Preacher & Hayes, 2004) allows for estimation and significance testing of the indirect effect, through bootstrapping, which generates an empirical representation of the sampling distribution of the indirect effect, from which a confidence interval can be generated. Please see Hayes (2009) for a more comprehensive overview. The standard error and 95% CI for a*b are obtained by bootstrapping with 10,000 re-samples. ASI (anxiety sensitivity) is the independent variable (X); MNWS (abstinence-induced nicotine withdrawal; M1) and QSU-T (abstinence-induced smoking urges, total score; M2) are the mediators; and DELAY (abstinence-induced time delay to RA T; Y1) and CIG (change in cigarettes smoked: 0 = no change in cigarettes smoked from non-abstinent to abstinent RAT; 1 = increase in smoking during abstinent RAT relative to non-abstinent; Y2) are the outcomes. Covariates in all models included gender, FTND, CES-D, and the non-abstinent measure of the mediator (either MNWS or QSU-T) and non-abstinent outcome measure (time delay to smoking). CI (l) = lower bound of a 95% confidence interval; CI (u) = upper bound; → = predicts.