The purpose of this study is to evaluate the efficacy of the "Smart Management Strategy for Health (SMASH)" program, which is designed to help cancer patients overcome their cancer crisis proactively and grow positively.

<Hypothesis> This study hypothesizes that the intervention being provided (SMASH program) will demonstrate improvements in cancer survivors' health management in the fields of (i) physical activity, body mass index, and positive growth, (ii) self-management strategies of health (SMASH Assessment Tool; SAT), (iii) overall physical, mental, social, spiritual health conditions and Quality of Life (QoL), and (iv) the execution and maintenance of health habits ("10 Rules for Highly Effective Health Behavior").

<Patient registry> Cancer survivors, who have just completed their cancer treatments (surgery, radiation, chemotherapy), will be recruited from five medical centers in Korea and randomly allocated to one of following three groups: 2 experiment groups and 1 attention control group. This recruitment process would start after the approval of protocol by the Institutional Review Board (IRB), and proceed through following steps: (i) the physician in charge confirms that the patient has finished his or her treatment and determines whether the patient is eligible to participate in the study by checking the recent (less than one year) results of the patient's basic medical exams (blood pressure, body temperature, heart rate, respiratory rate, weight, and height) and basic lab tests (blood chemistry, electrocardiogram, chest PA, complete blood count, liver function test, BUN/Cr), (ii) A nurse explains the purpose and method of the study to the patient, and asks to complete informed consent form, (iii) the patient who agrees for participation will complete a brief screening questionnaire (Godin's Leisure Time Exercise, weight/height, and PostTraumatic Growth Inventory(PTGI)), (iv) the patient meeting the criteria as determined by the screening questionnaire is asked to complete the baseline assessment questionnaire at home, (v) cases who finish the baseline assessment questionnaire and meet all criteria are considered study participants and are randomly assigned to one of the three study arms.

<Quality control (patient data)> This study assumes that patients who are directly referred to the study by collaborating physicians are valid cancer cases. Data collected from study participants on screening forms will be reviewed by researchers at the central institution for missing responses and inconsistencies.

<Sample size>

The sample size of 477 participants was based upon the following assumptions:

• a two-sided Type I error of 0.05
• drop-out rate of 10%
• an attainment of goal behavior of 5% in the active comparator arm and 20% in the experiment arm, and a power of 90% to detect a between-arm difference

<Statistical analysis plan > The primary endpoint was based on three-outcome composite achievement of PA, weight and PTGI score at 12 months. All analyses will be conducted on the basis of intention-to-treat. Arm differences at 3, 6, and 12 months in behavior change (physical activity, body mass index, posttraumatic growth) will be tested with logistic regression, controlling for the respective baseline values. Arm differences in levels of Mini Dietary Assessment Index (MDI), execution of health habits, SMASH Assessment Tool (SAT), Quality of Life (QoL), health condition, incurred medical expenses, incurred Complementary and Alternative Medicine (CAM) expenses will be explored using a mixed model that estimates the effect of SMASH program over time, which will correlate repeated observations on particular participants after adjustment for baseline scores.

Inclusion Criteria:

• Aware of one's diagnosis of breast, lung, colorectal or gastric cancer

• less than 2 months has passed since one's completion of primary cancer treatment (including surgery, radiation, or chemotherapy)

• Performs poorly at baseline on at least one goal behavior, which includes the followings:

  (i) moderate exercise ≥150 min/week or strenuous exercise ≥75 min/week (*exception: ≥12.5 MET-hr/week for lung cancer patients) (ii) BMI within normal range (18.5-22.9) (*exception: ≥18.5 for lung cancer patients) (iii) Posttraumatic Growth Inventory (PTGI) score ≥72

Exclusion Criteria:

• Inability to speak or write Korean
• Medical conditions that would limit adherence to an unsupervised health management program (as confirmed by their referring physician; e.g. major depression, dyspnea)
• Currently pregnant or planning to be within the next year