%K Science & Technology, Life Sciences & Biomedicine, Oncology, Colorectal cancer, Metastatic disease, Patient characteristics, Prognosis, Stratification, Clinical trials, Delphi survey, CLINICAL-TRIALS, SURVIVAL, BEVACIZUMAB, METAANALYSIS %X Background Patient characteristics and stratification factors are key features influencing trial outcomes. However, there is substantial heterogeneity in reporting of patient characteristics and use of stratification factors in phase 3 trials investigating systemic treatment of metastatic colorectal cancer (mCRC). We aimed to develop a minimum set of essential baseline characteristics and stratification factors to include in such trials. Methods We performed a modified, two-round Delphi survey among international experts with wide experience in the conduct and methodology of phase 3 trials of systemic treatment of mCRC. Results Thirty mCRC experts from 15 different countries completed both consensus rounds. A total of 14 patient characteristics were included in the recommended set: age, performance status, primary tumour location, primary tumour resection, prior chemotherapy, number of metastatic sites, liver-only disease, liver involvement, surgical resection of metastases, synchronous versus metachronous metastases, (K)RAS and BRAF mutation status, microsatellite instability/mismatch repair status and number of prior treatment lines. A total of five patient characteristics were considered the most relevant stratification factors: RAS/BRAF mutation status, performance status, primary tumour sidedness and liver-only disease. Conclusions This survey provides a minimum set of essential baseline patient characteristics and stratification factors to include in phase 3 trials of systemic treatment of mCRC. Inclusion of these patient characteristics and strata in study protocols and final study reports will improve interpretation of trial results and facilitate cross-study comparisons. %D 2018 %O This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. %I ELSEVIER SCI LTD %A KKH Goey %A H Sorbye %A B Glimelius %A RA Adams %A T Andre %A D Arnold %A JD Berlin %A G Bodoky %A A de Gramont %A E Diaz-Rubio %A C Eng %A A Falcone %A A Grothey %A V Heineman %A HS Hochster %A RS Kaplan %A S Kopetz %A R Labianca %A CH Lieu %A NJ Meropol %A TJ Price %A RL Schilsky %A H-J Schmoll %A E Shacham-Shmueli %A Q Shi %A AF Sobrero %A J Souglakos %A E van Cutsem %A J Zalcberg %A MGH van Oijen %A CJA Punt %A M Koopman %V 100 %T Consensus statement on essential patient characteristics in systemic treatment trials for metastatic colorectal cancer: Supported by the ARCAD Group %J European Journal of Cancer %L discovery10054713 %P 35-45