Moderators of the intention–behavior relationship in influenza vaccinations: Intention stability and unforeseen barriers

Abstract

Intentions and behavior are consistently correlated to one another. Although this relationship is strong, it is not perfect. What causes a person's behavior to deviate from previous intentions? This study examined the impact of two factors—intention stability and unforeseen barriers—on the intention–behavior relationship. In a longitudinal study of 101 university faculty and staff, more stable intentions over a four-year period led to stronger intention–behavior agreement for influenza vaccination in the fourth year. To investigate the role of unforeseen barriers, we took advantage of the fact that in the first year of the study flu shot availability was delayed, forming a barrier that arose after intentions to vaccinate were measured, but before the behavior could be carried out. As a result, the intention–behavior relationship was weaker in this year of the study than in the following years when no such barrier occurred. Both of these results help to elucidate the reasons why intentions and behaviors are not always aligned.

Keywords:

• Intention stability
• barriers
• intention
• behavior

Notes

¹ One might worry that including the independent variable (Spring 2003 intention) within the moderator (intention stability) constitutes a confound. To check whether this influenced the findings, we also created a stability measure that did not include the Spring 2003 data. Stability from 2000–2002 was used to moderate the intention–behavior relationship in 2003. Again, because of skewed data, we dichotomized the stability variable into perfectly stable (n = 69) and not perfectly stable (n = 32). The intention–behavior correlation for individuals who were perfectly stable (r = 0.81, p < 0.0001) was still significantly higher than for those who were not perfectly stable (r = 0.52, p = 0.002; z _diff = 2.5, p = 0.012).