Recruitment:
Patients are included from colorectal surgical departments in Aarhus, Randers, Herning and Aalborg. These centres cover one third of all Danish rectal cancer patients.
Patients are approached at the postoperative visit in the outpatient clinic where they are presented for the pathology results, approximately 2 weeks after primary surgery. The doctor provides short oral information about the study and hand out written information.
Following that, a research nurse makes contact with the patient by telephone a few days later, in order to clarify whether the patient wants to participate or not. Participation requires written informed consent and baseline information from the patient prior to randomisation.
Sample size:
An initial estimation of sample size showed, that a total of 334 participants were needed in order to obtain statistically significant results (alpha 0.05, beta 0.20, SD 13, minimally important difference 4 points on the TOI-score). The assumed standard deviation (SD) used for this estimation was based on studies where setting and populations differ substantially from ours.
Therefore, an interim analysis of the main-outcome (Trial Outcome Index - TOI) has been performed in order to determine a more precise SD. In an updated sample size estimation, the following preconditions are listed: 10.4 SD, 0.05 alpha-value, 0.20 beta-value, an expected difference of 4 points on the TOI-scale and an expected total drop-out of 30%.
Furthermore, additionally 15% are added to the sample size, due to the assumption that the outcome data will be non-parametric. Thus the conclusion from the updated sample size estimation is that a total of 324 participants are needed in order to obtain statistically significant results.
Drop-out is defined by: verified metachronous recurrence, metastasis or other primary cancer, death, emigration from the participating regions or if a participant leaves the study.
Data:
Most data is collected using questionnaires, administered by the patient (Patient-reported outcome measures -PROM's).
Patients are asked to complete a questionnaire at baseline (time of inclusion), and then at 12 and 36 months after surgery. The questionnaires consists of questions regarding symptom burden and quality of life, specific symptoms, patient activation, self-efficacy, patient involvement, patient information and needs in the follow-up period, and how they have been met by the Health care system.
Data regarding recurrence of cancer and mortality is collected from the Medical charts, while data regarding socioeconomic factors is derived from national registers and data on comorbidity is extracted from the national clinical database for colorectal cancer surgery.
Finally, data on health care utilisation in the follow-up period will be collected from national registers, in combination with information from patient records (limited access).
Statistical analysis:
Outcomes will be analyzed using methods for repeated measurements, and survival analysis. Any difference between the two allocation groups will be significance tested, and adjusted for covariates, using multiple regression analysis.
Differences in demographics between the two groups will be calculated and significance tested using a chi2-test (dichotomous and categorical data) and t-test (numerical data).
Quality-adjusted life years will be calculated using standard health economic methods and in collaboration with an expert in health economics.
Study timeline:
Development of the intervention was performed during the second half of 2015. Inclusion of patients in the RCT was initiated in February 2016, and is expected to be complete by the 31st of July 2018.
With a three-year follow-up period, the final results from the study will be analyzed and ready for publication by the end of 2021.
Ethical considerations:
The risks and ethical concerns related to the project are limited, but there are some potential concerns. Removing routine follow-up could lead to a delay in detecting asymptomatic local recurrences. However, patients having symptoms with the opportunity of self-referral may get an earlier detection of recurrence.
Answering the questionnaire could remind participants about their disease and lead some patients to unpleasant or stressful situations.
Patients agreeing to participate should feel secure in whatever group they are randomized to follow.
The study follows the ethical principles in the Helsinki Declaration, and is reported and approved by The National Committee on Health Research Ethics as required.
Data is handled and stored, according to national law and only anonymised results will be published. The study is reported and approved by the Danish Data Protection Agency.
