Plain English Summary
Background and study aims
In Switzerland, lung cancer is the first cause of cancer death, and in women, lung cancer will soon surpass breast cancer as the first cause of cancer death. Thus, effective smoking cessation interventions are necessary, and these interventions need to be widely disseminated. Smartphone-based support can reach thousands of smokers and have a substantial public health impact, in particular in the majority of smokers who would otherwise try to quit by themselves, without help and with little chance of success. The Stop-tabac fully-automated application (app) for smartphones was launched in 2012 and is now mature and ready for a test of its efficacy. It was ranked among the best five smoking cessation apps worldwide in a recent academic review. The services available on this app include: immediate feedback during episodes of craving and tobacco withdrawal symptoms; an interactive “coach” that provides individually-tailored counseling messages based on responses to a questionnaire (personal profile); a discussion forum (“The Tribe”) where participants receive support from other users; fact sheets; a calculator of cigarettes not smoked, money saved, and years of life gained; and a module on nicotine replacement therapy that includes personalized feedback. The aims of this study are to assess whether this app is effective for smoking cessation, to measure the size of its effect, and to examine whether the outcome is influenced by the personal characteristics of the participants.
Who can participate?
Daily cigarette smokers aged over 18
What does the study involve?
Participants are randomly allocated to either use the Stop-tabac app for 6 months or to use a placebo (dummy) app. Participants are followed up after 1 week, 1 month and 6 months to ask whether they have stopped smoking.
What are the possible benefits and risks of participating?
Participants will not be paid. They will have a chance of accessing a comprehensive smoking cessation app for smartphones, and they will contribute to the science on this topic. There is no risk associated with the behavioral program and the data collection procedure. There is a risk that data may be accessed by hackers. The researchers will make every effort to minimize this risk by using appropriate security measures.
Where is the study run from?
ISG - Faculty of Medicine - University of Geneva (Switzerland)
When is the study starting and how long is it expected to run for?
December 2016 to December 2021
Who is funding the study?
Swiss National Science Foundation
Who is the main contact?
Prof. Jean-François Etter
Prof Jean-François Etter
9 ch. des Mines
Impact of a smartphone application on smoking cessation: a randomized controlled trial
An application for smartphone will help smokers stop smoking.
Not provided at time of registration
Two-arm parallel-group individually randomized “placebo”-controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet
The trialists will randomly assign 5200 smokers to either using the Stop-tabac application for smartphones for 6 months or to use a placebo application. Stop-tabac is a fully-automated application (“app”) for smartphones that includes:
1. Immediate feedback during episodes of craving and tobacco withdrawal symptoms
2. An interactive “coach” that provides individually-tailored counseling messages based on responses to a questionnaire (personal profile). These automated messages are sent regularly during 6 months
3. A discussion forum (“The Tribe”) where participants receive support from other users
4. Fact sheets; a calculator of cigarettes not smoked, money saved, and years of life gained
5. A module on nicotine replacement therapy that includes personalized feedback
Follow-up after 1 week, 1 month and 6 months.
Primary outcome measure
Self-reported smoking cessation at 6 months (no puff of tobacco in the past 4 weeks). All data will be self-reported via online questionnaires. Participants can use any device to answer (smartphone, tablet, laptop, desktop). There will be no biochemical validation of smoking status. Assessed 4 times: at baseline, and 1 week, 1 month and 6 months after the participant’s target smoking cessation date.
Secondary outcome measures
1. Point prevalence of smoking abstinence at 6 months (no puff of tobacco in the previous 7 days)
2. Russell Standard (<5 cigarettes in the past 6 months plus no puff of tobacco in the past 7 days)
3. Abstinence of any tobacco and e-cigarette use at 6 months (no use in the previous 7 days)
4. Motivation to quit
5. Quit attempts (number and duration)
6. Confidence in ability to quit
7. Use of nicotine therapy
8. Use of e cigarettes and heated tobacco products
All data will be self-reported via online questionnaires. Participants can use any device to answer (smartphone, tablet, laptop, desktop). There will be no biochemical validation of smoking status. Assessed 4 times: at baseline, and 1 week, 1 month and 6 months after the participant’s target smoking cessation date.
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Daily cigarette smoker
2. Has been a daily smoker for at least one year
3. >18 years old
4. Sets a target quit date within one month of enrollment and commits to quit on this date
5. Provides informed consent online
6. Commits to answer all follow-up questionnaires, and commits to use the app
7. Owns a smartphone with Android operating system and has regular access to the Internet
8. Provides a postal address and telephone number, and a valid e-mail address
9. Lives in Switzerland or in France
Target number of participants
Participant exclusion criteria
Prior use of the Stop-tabac app for smartphones (self-report)
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
ISG - Faculty of Medicine - University of Geneva
9 chemin des Mines Campus Biotech
University of Geneva
9 ch. des Mines
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
Swiss National Science Foundation, Fonds National Suisse de la Recherche Scientifique, Fondo Nazionale Svizzero per la Ricerca Scientifica, Fonds National Suisse, Fondo Nazionale Svizzero, Schweizerischer Nationalfonds, SNF, SNSF, FNS
Funding Body Type
private sector organisation
Funding Body Subtype
Results and Publications
Publication and dissemination plan
The trialists plan to publish the study protocol in a peer-reviewed journal. The results will be published in a peer-reviewed scientific journal and presented at an international conference.
IPD sharing statement
A data management plan was submitted and accepted by the Swiss National Science Foundation, which supports this project. The shared SPSS data file, with participant-level data, will be fully documented, which means that the variable labels and value labels will include the full wording of questions and of response options.
An accompanying README.TXT file will include:
1. An explanation of how and when the data were collected and prepared
2. The names and addresses of the investigators
3. The conditions required to access the data
4. A description of the original study and of the data collection methodology
5. Additional information about how the data were collected, processed and analyzed, giving more technical details than in the publications
6. The SPSS syntax used to transform variables
7. A list of the publications based on these data
The trialists will deposit the participant-level data, with sufficient accompanying metadata and information, on the future repository of Swiss Universities (DLCM project), that will most certainly be available when the study
ends (https://scicore.unibas.ch/projects/dlcm/). If the DLCM project does not materialize, the trialists will archive the data in the ZENODO repository (https://zenodo.org/). The data file will be identified by a DOI. The data will be made available after the publication of the main article describing the study’s results. In the final shared data file, the data will be anonymous, and any indication allowing the identification of study participants will be deleted (names, addresses, e-mails, phone numbers). There will be no possibility to track the identity of study participants. As required by Swiss law, the study will be approved by the ethics committee of the canton of Geneva. This approval will include the data collection, storage and sharing procedures. Study participants will be informed that their responses to the questionnaires will be made publicly available in an anonymous format. This will be included in the informed consent form.
Intention to publish date
Participant level data
Stored in repository
Basic results (scientific)