COLORECTUM+ Digital System for Postoperative Quality Improvement in Colorectal Cancer

Our mobile application aims to monitor the three-month follow-up rate for patients, assessing whether they adhere to the follow-up schedule as outlined，providing a streamlined approach to track post-discharge appointments. By utilizing real-time notifications and easy scheduling features, the app encourages patients to attend their follow-up visits, ensuring continuity of care. The application records and analyzes data on scheduled and completed appointments within three months post-discharge, offering insights into adherence rates and identifying factors impacting follow-up compliance. This data-driven approach helps healthcare providers improve patient outcomes and optimize follow-up strategies.

User adherence with the mHealth intervention will be measured by following approaches

• User log-in data retrieved from app or website：

• Number of log-ins to app
• Length of time spent in app
• Manual user data entry in app - The frequency at which users manually enter data in the app, such as blood glucose level, weight, date and time when medicine was taken, or blood pressure values.

Quality of life (QoL) was captured by survey with the 27-Item Functional Assessment of Cancer Therapy-Colorectal (FACT-C), which consists of 27 items with physical component summary and mental component summary scores. The score range is 0 to 136, with higher scores indicating better quality of life.

Unplanned Hospitalization Days" refers to the duration of hospital stays that occur outside of a patient's scheduled follow-up plan. These unplanned admissions indicate instances where a patient's condition requires urgent or unexpected inpatient care, reflecting potential health complications or acute needs beyond the regular follow-up schedule. Monitoring unplanned hospitalization days can provide valuable insights into patient health outcomes, care management, and the effectiveness of follow-up programs.

"Potentially Preventable Emergency Visits" are defined as emergency visits where the primary diagnoses include conditions such as anemia, nausea, fever, dehydration, neutropenia, diarrhea, pain, pneumonia, sepsis, or vomiting. These visits represent cases where timely outpatient care, effective management, or preventive measures might have reduced the need for emergency intervention. Tracking potentially preventable emergency visits helps healthcare providers identify areas for improvement in outpatient management and preventive care, ultimately aiming to reduce avoidable strain on emergency services.

"Number and Distribution of Alerts" involves collecting patient-reported symptoms, medication information, and health data such as tumor markers and imaging results through symptom questionnaires and patient self-reports. When risks or abnormalities are detected, alerts are automatically triggered. Alerts are categorized by urgency and severity into yellow, orange, and red levels. Descriptive statistical methods are used to analyze alert occurrences, with frequencies and percentages summarizing the number and reasons for each alert type. The average number of alerts triggered per patient, along with the standard deviation, is calculated. Correlation or regression analyses are applied to explore relationships between the number of alerts and other variables.

The FACIT-TS-PS Questionnaire (Functional Assessment of Chronic Illness Therapy - Treatment Satisfaction - Patient Satisfaction) is a tool designed to evaluate patients' satisfaction with their overall treatment and the use of specific applications. It assesses various aspects of treatment satisfaction, including the effectiveness, convenience, and overall experience of therapy, as well as the patient's satisfaction with digital applications used as part of their care. The insights gained from this questionnaire help healthcare providers improve treatment approaches and enhance the patient-centered design of healthcare applications.

The System Usability Scale (SUS) is a standardized questionnaire used to assess the usability of a system. It consists of 10 items with a five-point Likert scale, allowing users to express their level of agreement or disagreement with statements about the system's functionality and ease of use. The SUS provides a quick and reliable measure of overall usability, enabling evaluators to identify potential improvements and gain insights into users' experiences.

The nutritional status of the selected patients was evaluated using the Patient-Generated Subjective Global Assessment (PG-SGA) questionnaire. The PG-SGA questionnaire consists of two parts: the PG section, which is completed by the patient through self-assessment and includes information on recent weight changes, recent dietary intake, symptoms and signs related to diet, activity, and function; and the SGA section, which is filled out by the investigator after assessment, including the patient's age at onset of disease, metabolic stress status, and physical examination findings. The total score from both sections constitutes the PG-SGA score, with higher scores indicating worse nutritional status. A PG-SGA score of 4 or above is indicative of malnutrition