Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT03191019 |
Other study ID # |
15-349 |
Secondary ID |
FONIS SA15I20120 |
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
November 6, 2017 |
Est. completion date |
November 4, 2018 |
Study information
Verified date |
November 2021 |
Source |
Pontificia Universidad Catolica de Chile |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The purpose of this study is to determine whether a mobile-phone based intervention is
effective in supporting smoking cessation among Chilean women
Description:
This protocol corresponds to a single-blind, two-arm, randomized clinical trial of a smoking
cessation intervention based on a mobile-phone app. Eligible participants are Chilean women
from the Metropolitan Region, who smoke daily (at least one cigarette per day) or weekly (at
least 7 cigarettes per week), and who are willing to make a quit attempt within one month of
enrollment. Study will be advertised on the local radio, primary care centers, smoking
cessation services and through social media campaigns. Study information will be available
online. Potential participants will be asked to register their interest by sending an email
to the study. Research assistants then will contact respondents by phone in order to complete
a baseline questionnaire about sociodemographic variables, characteristics of tobacco
consumption, and to assess eligibility for the study. Eligible participants will be then
randomized to the intervention group or control group using a computerized and automated
process, in blocks of 6. A minimization algorithm balancing for Fagerstrom score for nicotine
addiction (≤5, >5) will be used. Researchers who will gather data and those who will measure
carbon monoxide in exhaled air will be masked to treatment allocation.
Each participant will be emailed the link with either the intervention or the control version
of the mobile-phone app. Once participants download the app, they will be asked to provide
informed consent by clicking the "accept" or "reject" button in the app.
Participants randomized to the intervention app will be sent motivational and preparatory
content for the first two weeks, and they will be asked to set a quit date within 4 weeks
from enrollment. The mobile app will send an average of 4 messages per day during the first
month after quit date, followed by three messages per week up to the end of the study at
month 6.
The intervention program was designed based on current best evidence on strategies to support
smoking cessation, and included work of Chilean experts in smoking cessation. The design of
the intervention app also included the opinion and preferences of potential participants who
participated in focus groups during intervention design. The intervention app includes
motivational messages, tips on stress management, on how to ask support from friends and
family, how to use distraction techniques and how to deal with cravings, lapses and early
relapse.
The intervention app also includes a "help button" which provides extra messages in case of
cravings and a "lapse/relapse button", which provides advice about what to do if the
participant returned to smoke. The control group will receive a control app which will send 1
message every two weeks thanking participants for taking part in the study, and encouraging
them to stay in the study for the 6 month follow-up period. After completing the 6-month
follow-up evaluation, the control group will be offered access to the intervention app.
Women will not receive financial compensation for their participation in the study. In order
to increase retention, participants in both arms will be told that they would be entered into
a lottery for different prizes after answering the 6-month follow-up questionnaire.
For the 4-week, 3-month and 6-month follow-up, a link to an electronic follow-up
questionnaire will be emailed to all participants. Reminders will be sent to non responders
and if they still do not respond, additional email reminders will be sent. If participants
still do not respond, research assistants will call them by phone in order to capture the
primary outcome of the study. At 6-month follow-up, participants who reported having quit
smoking will be asked to attend to the local primary care center in order to measure carbon
monoxide in exhaled air. All measurements will be performed by research assistants who are
masked to treatment allocation.
Sample size was calculated based on previous studies. Twenty-eight percent quitting in the
intervention group and 13% in the control group was expected. To achieve 90% power with a
significance level of P ≤ .05 (2-sided), and including a 20% attrition for the 6 month
follow-up evaluation, a sample size of 400 was estimated. In order to take into account that
the size effect associated to the intervention could be lesser in Chile than the reported for
other countries, investigators defined a 90% power for the sample size calculation.
Investigators plan to conduct analyses for the whole sample and also for subgroups of age
(<35 years, ≥35 years), nicotine addiction (Fagerstrom score ≤5, >5), educational level (<8
years, 8-12 years, ≥12 years), and use of other smoking cessation treatments or services
during the trial (yes, no).
All statistical analyses for clinical effectiveness will be undertaken on an
intention-to-treat basis. For missing observations in the primary outcome, two methods will
be used: last value carried forward method and multiple imputation method, as attempts to
correct for potential bias caused by missing data.
Analyses for adverse effects outcomes will be performed on a per-protocol basis.