Introduction:
Taiwan has around 4million smokers, resulting in 27,000 deaths annually. Despite the knowledge of smoking hazards and intention to quit smoking, the abstinence rate is below 20%. The objective of this study is to evaluate if a mobile app based smoking cessation intervention, embedded with the concept of recommender system and computer tailoring is effective to increase the abstinence rate in Taiwan.

Methods:
This intervention would record data from two sources: the clinical study and public study. The patients in clinical study will be recruited in smoking cessation centers in Taiwan with 50 patients in the intervention group using the mobile app, and 50 patients in control group. They will be followed-up for 6 months and their expired carbon monoxide and urine cotinine levels will be used for the assessment of being smoke-free. In public study, web users intended to quit smoking will be able to download the same mobile app and randomly allocated to an intervention group, receiving personalized motivational messages or to a control group that receives basic motivational messages. They will also be assessed through routine self-reported questionnaires for 6 months.

Expected Results:
Preliminary results show that health recommender system based mobile motivational messages have a positive influence in smoking cessation towards smokers willing to quit smoking.

Discussion:
To our knowledge this is the first mobile app based intervention in Taiwan to make use of combination of I-Change behavioral change model with health recommender system and computer-tailoring for smoking cessation. If found effective, our solution could help provide new clinical insights for smoking cessation.