Shrinking the Size of the Tobacco Power Wall and Restricting the Number of Tobacco Products Displayed to Reduce Adolescent Tobacco Use
Phase: NA
Conditions: Tobacco Use
Sponsor: RAND

Shrinking the Size of the Tobacco Power Wall and Restricting the Number 
of Tobacco Products Displayed to Reduce Adolescent Tobacco Use 
NCT04632030 
August 17, 2023 
 

Study Protocol 
Study objective.   The overall objective of this research is to experimentally evaluate 
legally viable approaches to reducing the impact of the POS retail environment on 
adolescent risk of using four classes of tobacco products: cigarettes, ENDS, smokeless 
tobacco, and LCCs.  Specifically, we propose to investigate the extent to which reducing 
the size of the tobacco powerwall display reduces adolescents’ risk of future use of 
tobacco.   
 
Study design.  The experimental conditions that we will compare in this study are: 
large power wall with a large number of products (status quo/control), small power wall 
with a small number of products displayed, and a medium sized power wall with a 
medium number of products displayed. The studies will take place in the RAND 
StoreLab (RSL), a life-sized replica of a convenience store that was developed to 
experimentally evaluate how altering aspects of tobacco advertising at POS influences 
tobacco use.   
 
Methods.  The study was approved by the RAND Human Subjects Protection 
Committee. Young people were recruited from the community through standard 
advertising campaigns.  Interested individuals completed a telephone screening to 
determine eligibility.  Eligible individuals completed informed consent (or consent and 
assent if minors).  Participants completed a baseline questionnaire that assessed 
demographics, tobacco product cognitions, smoking and tobacco use, and convenience 
store shopping habits.  Participants were then randomized to one of the three 
experimental conditions.  They were provided with a $10 (fake) RSL gift card and asked 
to shop in the RSL for whatever they wanted, for as long as they wanted.  They were 
asked to purchase at least one item and check-out and pay for the item(s) as they would 
in any convenience store.  A confederate who was not involved in the consent or survey 
process served as the cashier. This cashier scanned the selected items for a total price, 
scanned the gift card, and bagged the items.  Although no participants attempted to 
purchase tobacco from the RSL in this study, any such attempts would have been met by 
the cashier with a request for age identification and the purchase attempt would have 
been declined (i.e., because no participants were > 21 years old).   After exiting the RSL, 
participants completed the dependent measures.  They then: underwent a graduated 
debriefing; were asked to guess the study’s purpose; and were told that they would be 
unable to retain the items they selected from the RSL.  Participants then viewed a short 
tobacco media literacy video and received printed smoking prevention materials. 
Finally, they received a $40 gift card as compensation. 
 
Statistical analysis plan 
First, we evaluated whether randomization distributed pre-shopping baseline 
characteristics evenly across the experimental conditions.  These univariable analyses 
used either t-tests or chi-squared tests to evaluate significance (depending on variable 
distribution).  Next, we used logistic regression to evaluate the relationship between the 
experimental conditions and post-RSL shopping risk of using cigarettes; ENDS LCCs, 
and smokeless tobacco.  Lifetime use of each product under investigation was included 
in the appropriate model as a covariate (0 = no use; 1 = any lifetime use).  Finally, 
because both age (continuous) and education (0 = still in middle/high school; 1 = high 

school graduate or more) are related to tobacco use, these variables were also included 
as covariates.  Each reduced tobacco powerwall condition was compared to the all status 
quo/control condition (reference) using planned contrasts.