Here is the design of a clinical trial:

Official Title: Predictive Value of Innovative Prognostic Markers (Gut Microbiota, Sarcopenia, Metabolic Syndrome and Obesity) on Surgical and Oncologic Results in the Management of Sporadic Colorectal Adenocarcinoma.

Included conditions:
- Colorectal Neoplasms
- Microbiota
- Prognosis
- Metabolic Syndrome
- Sarcopenia

Study Armgroups:

Interventions:
- {'type': 'OTHER', 'name': 'no intervention', 'description': 'The aim of this translational research project is to study the impact of these new prognostic tools on surgical and oncologic results in a prospective cohort of patients who underwent CRC surgery at the Digestive Surgery Department of the University Hospital of Clermont-Ferrand (France)'}

Primary Outcomes:
- {'measure': 'Overall survival (OS)', 'description': 'defined by the time between surgery and last follow-up. The 5 years overall survival will be recorded.', 'timeFrame': 'at 5 years'}

Please estimate the sample size based on the assumption: 
two-sided type I error at 5%, statistical power greater than 90%
Estimation of sample size
          Sample size estimation is based on literature about statistical power and number of prognostic factors. According to recommendations reported by Harrell, Green and Hsieh et al.,44â46 we plan to include 300 patients in order to identify prognostic factors for 5-year survival for a two-sided type I error at 5%, a statistical power greater than 90% and 5-year survival equals 55% for rectal cancer patients and 60% for colon cancer patients.
          A sequential analysis will be carried out every 100 inclusions in order to estimate the statistical power calculated from the work of Hsieh et al
45 and Demidenko47 after estimating the number of factors actually tested and on the basis of preselected factors, determined according to univariate analysis and clinical relevance.