Study Design and Population
Customers were screened for eligibility to the RCT from 8 community pharmacies ().
Profile of the randomized controlled trial (using CONSORT guidelines).
Sample Size and Strategy
In total, 1259 customers were screened for eligibility; 213 customers were eligible and 160 were recruited, the others declined the invitation to participate for a range of very different reasons. Eighty participants were recruited to the control group and 80 to the intervention group.
The smoker’s face simulations were created using a digital photograph (6.0 megapixels) taken of the intervention participants and uploaded to APRIL Face Aging software version 2.5 on a laptop computer.
The RCT was conducted between January 2010 and December 2010 and all follow-up surveys were completed by June 2011. The final 6-month follow-up showed a response rate of 77.5% for the control group and 72.5% for the intervention group. The demographic and baseline smoking behaviors of recruited participants are shown and compared between groups (intervention versus control) in .
Demographic and baseline smoking profile of study participants (N=160).
There were more females and lighter smokers (smoking up to 5 cigarettes per day) in the intervention group; however, there were no statistically significant differences between the control and intervention groups on demographic or smoking dependence variables at baseline. No participants were revealed to have body dysmorphia. A number of questions on the survey were designed to gather the respondents’ opinions of self-perceptions and their attitudes toward their smoking behavior. These questions were taken from an earlier survey [11
], and showed that the groups were generally well matched. However, a greater proportion of the intervention group appeared to be concerned about their physical appearance (82.5% versus 67.5%, χ2
=.03), and believed that facial wrinkles were associated with smoking (98.8% versus 85.0%, χ2
=.002). There was no difference in the proportion of participants in each group who had made at least 1 attempt to quit smoking in the past (68.4% versus 70.9%, χ2
Primary Outcomes Measured
shows the response rates to the follow-up surveys, and the change in smoking behavior over the study duration. There was a significant difference in the proportion of participants self-reporting to have successfully quit smoking by the 6-month survey. Assuming that participants who failed to complete the final follow-up survey continued to smoke, only 1 of 80 control participants (1.3%, 95% CI 0-6.7) were confirmed nonsmokers compared to 11 of 80 participants in the intervention group (13.8%, 95% CI 7.8-22.9). This difference in confirmed quitting is statistically significant (χ2
1=9.0, P=.003). The intervention group contained a larger proportion of participants responding to the question: “I care about how people think I look.” A logistic regression model was used to investigate the association between treatment group and self-reported quitting after adjustment for this difference as well as the small differences between groups in gender and nicotine dependence. The difference remained statistically significant after adjustment for these potentially confounding variables (P=.003).
Pattern of survey completion and change in smoking behavior at 6-month follow-up (N=160).
A similar model using confirmed quitting as the dependent variable showed an adjusted P value for the treatment group of P=.03.
also shows changes in the Fagerström smoking dependence score. The 6-month score was grouped into the 5 broad dependence level categories and compared with baseline data. There was a significant difference in change in smoking dependence between groups (χ2
2=26.2, P<.001), with 14% of the control group moving to a lower category compared to 51% of the intervention group doing so.
A random effects regression model was used to model the mean change in Fagerström score from baseline by using data from all follow-up surveys The control group did not experience a significant drop in Fagerström score over the study (P=.36), whereas the participants in the intervention group dropped by an average of approximately 1.9 points (P=.002). The change in mean scores over the whole study was significantly different between treatment and control groups (P<.001).
Although there were no differences between participants at baseline, the regression models were extended to adjust for the gender and age of the participant, and the number of cigarettes smoked at baseline. The models were fitted to the control and intervention group separately because it was clear that changes in score appeared only in the intervention group. For the control group, there were no associations between change in score and age (P=.14), gender (P=.72), or baseline consumption (P=.49). However, for the intervention group, age (P<.001) and baseline consumption (P<.001) were significantly associated with change in score, whereas gender (P=0.34) was not associated. Older participants were less likely to reduce their score than younger participants (P=.001), suggesting that the intervention may have a greater effect on the younger participants. Participants who smoked more than 10 cigarettes per day showed a significant drop in score on the Fagerström scale of at least 1 point (P<.001) independent of age. Participants smoking 6 to 10 cigarettes per day obtained a lower score, but this change was not statistically significant (P=.07), whereas light smokers (0-5 cigarettes per day) showed no change in score.
Secondary Outcomes Measured
Total costs of implementing the intervention from a health sector perspective were AU $463, or the equivalent of AU $5.79 per participant ().
Economic analysis of photoaging service.
With an additional 10 quitters confirmed in the intervention group compared to the control group (11 and 1, respectively), the incremental cost-effectiveness ratio (ICER) was AU $46 per additional quitter, or the equivalent of AU $74 per additional lifetime quitter. Cost offsets of AU $2144 from a reduction in the health care costs of quitters resulted in the intervention potentially generating net total cost savings of AU $1778. In the best-case scenario, the ICER was AU $41 per additional quitter and net total cost savings were AU $2346. Corresponding figures for the worst-case scenario were AU $71 per additional quitter and AU $1316, respectively.
The mean cost that the participants indicated that they were willing to pay for the digital aging service was AU $20.25, which exceeded the mean cost per participant for delivering the service (AU $5.79). The median cost they were willing to pay was AU $20, similar to the mean value. More than 80% of participants said they would be more likely to use the pharmacy to purchase future smoking cessation therapies and to use it more for other purchases. More than 80% of participants also thought their friends would be willing to pay for the service, and all but 2 participants said they would recommend the photoaging intervention to 1 or more friends who were smokers.