Personalized Feedback for Distress Intolerant Smokers
Phase: NA
Conditions: Anxiety Disorders, Depression, Psychological Distress, Tobacco Dependence, Smoking, Tobacco, Smoking, Cigarette
Sponsor: University of Houston

Personalized Feedback for Distress Intolerant Smokers 
Study Protocol and Statistical Analysis Plan 
NCT03918031 
IRB Approval Date: 02/15/2019 
 

Study Protocol 
Recruitment. Participants were recruited nationwide through advertisements and physician 
referrals. Specifically, recruitment techniques included electronic media (e.g., university 
listservs, social media, websites, craigslist) and flyers in community-based organizations (e.g., 
campus, community health centers). 
 
Pilot Procedure. Interested individuals completed a phone pre-screen. Individuals who were 
eligible at the pre-screen and willing to participate in the study were contacted and scheduled for 
an in-person baseline appointment at the laboratory, wherein full eligibility was assessed, and 
informed consent was completed. At the in-person baseline appointment, participants were 
provided informed consent and completed additional eligibility screening, including (1) a pre-
intervention online eligibility survey (~90 minutes) and (2) and measures administered by a 
trained research assistant (e.g., CO assessment, breath holding tasks; ~20 minutes). Following 
completion of these tasks, a trained research assistant determined the participant’s eligibility. 
Subjects deemed ineligible were unable to participate in the intervention, provided with 
resources, and compensated $10 for their time. Participants deemed eligible completed a 
computer delivered intervention (~ 90 minutes) of the Active personalized feedback intervention 
(PFI). Following the intervention, participants completed a post-intervention online survey (~15 
minutes) and tasks with a trained research assistant (~5 minutes). Additionally, participants 
completed an individual semi-structured interview with a trained researcher (~10 minutes). The 
semi-structured interview included questions about the personalized feedback format and 
content, and suggestions to improve the feedback. The investigative team reviewed the feedback 
from the first 5 eligible participants and adapted/refined the intervention content as needed. We 
then present a revised version of the PFI to an additional 5 eligible participants individually, and 
completed the same feedback/evaluation process. Changes and suggestions elicited from the 
second round of participants were integrated into the final PFI to be tested in the RCT phase. 
Participants were compensated $60 for their time. 
 
RCT Procedure. Interested participants were instructed to contact the research lab. Participants 
who expressed interested were sent a unique link to an online survey which included 
demographic and selected eligibility screening questions (e.g., cigarettes smoked per day, 
distress tolerance) that took approximately 10 minutes to complete. Each unique link could only 
be used one time. Individuals who were eligible at the pre-screen and willing to participate in the 
study were provided an additional unique link to complete an online baseline assessment. During 
the baseline assessment, informed consent was obtained electronically. The participant then 
completed an approximately 90-minute pre-intervention online survey that further evaluated 
eligibility criteria (i.e., re-evaluated distress tolerance) as well as assessed psychological and 
health-related constructs of interests. Participants who did not meet eligibility criteria were 
provided with referrals and compensated $10 in the form of an electronic gift card. To ensure 
quality responses, speeding checks were included and IP addresses and coordinates were 
checked to prevent multiple attempts to complete the survey by the same respondent. Moreover, 
unique links to participate were created for each participant at every stage of the study. 
Participants who met eligibility criteria were randomly assigned to complete either the (a) Active 
PFI (60-minutes) or (b) Control PFI (30-minutes). Following the completion of the program, 
participants were redirected to complete a post-intervention online survey (~15-minutes) to 
gather qualitative feedback and assess for treatment satisfaction. Eligible participants were 
compensated $60 in the form of an electronic gift card upon completing all portions of the 

baseline (e.g., pre-intervention survey, randomly assigned intervention, and post-intervention 
survey). Participants were then emailed a unique link to complete an online assessment at 2-
weeks and 1-month post-intervention to assess relevant psychological and health-related 
constructs of interest. The post-intervention online assessments took approximately 30-minutes 
(each) to complete. Participants were compensated with $30 in electronic gift cards for 
completing each of the follow-up assessments for up to $120 in electronic gift cards for 
completing the entirety of the study. 
 
Randomized Clinical Trial (RCT) Procedure: 
 
Control PFI Condition: The Control PFI included personalized feedback on motivation 
to change smoking, behavior through eliciting responses regarding importance, confidence, and 
readiness to quit smoking. Next participants were shown graphics depicting their perceptions of 
smoking behaviors (e.g., percentage of sex-matched adults who they believe currently smoke) 
and attitudes (e.g., percentage of individuals who they believe smoke that would like to quit) in 
comparison to normative values in the US. Participants were then guided through a variety of 
financial and health-related costs of smoking personalized to their smoking behavior (e.g., 
amount they spend on cigarettes, impact on life expectancy) as well as psychoeducation on 
dangerous chemicals currently used in cigarettes. Participants were also provided with various 
health benefits of quitting smoking. Finally, quit tactics were reviewed with participants (e.g., 
gradual reduction, nicotine replacement therapy) as well as the 5 D’s (i.e., Delay, Distract, Deep 
breaths, Drink water, and Discuss). The intervention included a racial/ethnic and sex-matched 
digital avatar that guided participants through the intervention. The Control PFI also provided 
audio and visual aspects to portray the relevant information and interactive games and activities 
to foster engagement. 
Active PFI Condition: The Active PFI included all of the components of the Control PFI 
as well as the addition of distress tolerance components. Distress tolerance components included 
personalized normative feedback about distress tolerance and its consequences. For example, 
participants were provided psychoeducation on what low distress tolerance is, what it can lead to 
(e.g., worsened mental health), and how their distress tolerance level compares to normative 
averages. Next, participants were provided psychoeducational information regarding relations 
between distress tolerance and smoking behavior (e.g., how distress tolerance influences 
smoking behavior). Finally, concrete evidenced-based strategies to encourage motivation and 
action steps for changing distress tolerance taken from intensive distress tolerance treatments 
were incorporated. Specifically, participants engaged in imaginal activities aimed at building 
tolerance for distress such as imagining a recent stressful event and imagining being around 
cigarette smoke. Participants were encouraged to continue to practice imaginal activities in order 
to build tolerance to distress. 
 
Statistical Analysis Plan 
 
The equivalence of the random assignment of groups regarding key baseline 
characteristics (e.g., demographics) and retention (i.e., 2-week, 1-month; 0 = completed and 1 = 
missed) were assessed. Differences between key baseline characteristics were also assessed for 
participants who completed all follow-ups (coded 0) versus participants who missed at least one 
follow-up (coded 1). Then, paired t-tests were conducted to assess change in credibility and 
expectancy between baseline and post-intervention. Latent growth curve (LGC) analyses were 
then conducted using Mplus version 8.6 using maximum likelihood. Multiple imputation using 

1,000 imputed datasets calculated in Mplus were used to handle missing data. LGC modeling 
was used to evaluate the overall trajectories across time of smoking related variables: (1) 
increased motivation, confidence, and intention to quit, (2) fewer perceived barriers for quitting 
smoking, and (3) reduced smoking rate. A conditional model was then specified to examine the 
impact of treatment (0 = Control PFI, 1 = Active PFI) on the slope factor for each of the stated 
outcome variables. Similar procedures were utilized for mood-related outcomes: (1) greater 
distress tolerance, (2) reductions in anxiety/depressive symptoms, and (3) increased willingness 
to use adaptive coping strategies. 
 
For all analyses, shape factors were set for the slope to be centered at the baseline 
assessment and the 1-month follow-up was fixed at 1.0. The 2-week follow-up was freely 
estimated. LGC analysis model fit was evaluated with the following fit indices: root-mean-
square (RMSEA; Steiger, 1990) and standardized root-mean-square residual (SRMR; Jöreskog 
& Sörbom, 1996) with values below .08 indicating acceptable fit (Little, 2013), Tucker-Lewis 
index (TLI; Tucker & Lewis, 1973) and comparative fit index (CFI; Bentler, 1990) with values 
at .90 or above indicating acceptable fit (Little, 2013). Effect sizes were interpreted in the 
Cohen’s d metric (i.e., small = 0.2, medium = 0.5, and large = 0.8) utilizing the partially 
standardized path coefficient.