Introduction: Colorectal cancer (CRC) is the second most common cancer among Chinese in Hong Kong and the second leading cause of cancer death in this population. Several screening strategies has been associated with improved survival and may affect patients' health-related quality of life (HRQOL). HRQOL impact should be used to adjust for survival in terms of quality adjusted life years (QALY) in the evaluation of cost-effectiveness of any intervention including screening.

Objectives: to determine the HRQOL and health preference of patients with different stages of colorectal neoplasm, and to determine the most cost-effective CRC screening strategy for increasing QALYs.

Design and Subjects: A longitudinal survey to collect data on HRQOL associated with colorectal neoplasm for Markov modeling on cost-effectiveness of CRC screening. A stratified sample of 420 patients with colorectal polyps and different stages of CRC will be recruited from colorectal clinics of Queen Mary Hospital for health preference and HRQOL assessment. The HRQOL over time will be measured at baseline, 6 and 12 months later. Health preference data will be integrated with cost and effectiveness data obtained from the literature to determine the cost-effectiveness of currently recommended CRC screening strategies by Markov modeling.

Main outcome measures: The primary outcome measure is the SF-6D health preference value and QALYs. Secondary outcomes are the SF-12v2 and FACT-C scores. The outcomes will be compared between patients with different stages of colorectal neoplasm. Markov modeling study will estimate the expected QALYs gained and incremental cost-effectiveness ratio for each CRC screening strategy.

Results: The study will provide information on HRQOL of patients with colorectal neoplasm to guide health services. The Markov Model will identify the most cost-effective CRC screening strategy for Hong Kong Chinese, which can inform policy makers and the public for the prevention of CRC of the population.

The aims are to determine the HRQOL and health preference (utility) of different stages of colorectal neoplasm in order to evaluate the cost-effectiveness of different CRC screening strategies for the Chinese population in Hong Kong.

The specific objectives are:

1. To determine the HRQOL preference values of patients in different stage of colorectal neoplasm in order to estimate the quality of life adjustment applicable to each stage of colorectal neoplasm.
2. To evaluate the HRQOL of patients with colorectal neoplasm in order to find out their concerns and needs.
3. To find out whether HRQOL preference of people with colorectal neoplasm changes with time.
4. To determine the expected life years gained from the reduction in the incidence and mortality rates of CRC for each CRC screening strategy base on literature review.
5. To determine the QALY gained from each CRC strategy by combining the preference value with life years gained.
6. To identify the most cost-effective CRC screening strategy and to determine the incremental cost per additional QALY gained compared to no screening, by Markov modelling.

The study hypotheses are:

1. Patients with colorectal neoplasm including those with polyps have lower HRQOL than the general population.
2. There is a gradient reduction in HRQOL preference among patients with different stages colorectal neoplasm from polyp to metastatic cancer.
3. HRQOL preference of patients with colorectal neoplasm is stable if there is no change in the disease stage.
4. Annual I-FOBT is the most cost-effective CRC screening strategy for the Chinese population in Hong Kong.

Inclusion Criteria:

• Age 18 years or above
• Have life expectancy of at least 6 months
• Have confirmed diagnosis of any of the following colorectal neoplasm classified by the screening surveillance guideline and UICC/AJCC (TNM) staging system
• Have given consent to take part in the study

Exclusion Criteria:

• Inability to understand or communicate in Cantonese or Chinese
• Significant cognitive impairment judged by the doctor to be unable to answer the questionnaire
• Too ill to carry out an interview
• Refuse to give consent

All Chinese patients of 18 years old or above with a histology of confirmed colorectal polyp or cancer for at least six months were recruited from specialist outpatient medical and surgical colorectal clinics of Queen Mary hospital in Hong Kong.