Objectives: (1) To replicate previous research finding that abstinence-specific social support during the active phase of quitting predicts short- and long-term smoking cessation treatment outcome. (2) To describe time-related changes in abstinence-specific support, including how support provided during middle and later phases of the quitting process is associated with treatment outcome.
Design: Combined data from three randomized clinical trials of smoking cessation treatment (N = 739) were analyzed using logistic regression and analysis of variance.
Main outcome measures: Measures included the Partner Interaction Questionnaire (PIQ; Cohen & Lichtenstein, 1990), a measure of smoking-related social support, and smoking status according to 7-day point-prevalence abstinence.
Results: Longitudinal analyses found that positive support peaked at week 12, decreasing thereafter. Positive support provided after week 12 did not differentiate between those who never quit smoking, those who quit and relapsed, and those who maintained abstinence. In contrast, negative support was monotonic and was useful at follow-up points for distinguishing between outcome groups.
Conclusion: These results suggest that positive and negative support are both important factors in the early phase of quitting, but it is the continued minimization of negative support that best predicts maintenance of nonsmoking.