Although the findings revealed statistically significant differences between the NCMIT and SI program (68% vs. 54%) and no significant difference in HBV vaccine completion between the SIT and SI programs, a question of clinical significance arises as the completion rate of the SIT participants (61%) is fairly close to the completion rate of the NCMIT at 68%. However, it is believed that clinical significance is present as the NCMIT is the only program found to be statistically different than the control program, and a cost–benefit analysis found the NCMIT program to be the most cost-effective program, as compared with the SIT and SI programs, for increasing HBV vaccine coverage among homeless adults (Greengold et al., under review). Thus, it is believed that these findings are clinically different as well.