Background: Frailty is traditionally assessed by a comprehensive geriatric assessment (CGA); there is no agreed upon standard for a CGA, and it is not feasible to implement in routine oncology practice. In contrast, the Edmonton Frailty Scale (EFS) is a simple questionnaire, requiring less than 5 minutes to complete, initially validated as a surrogate to the CGA in general medicine patients (Rolfson et al, 2006). We conducted a pilot study to establish if the EFS would add utility beyond clinician’s expertise. Methods: The EFS was administered to stage II-IV CRC patients ≥70 years, referred to a Medical Oncologist at a tertiary care centre. The EFS was completed by one of the investigators, with the treating oncology team blinded to results, and follow up of 14 months. Results: Forty-six patients were enrolled with the following characteristics: average age 76, 48% male, and 78% Zubrod performance status (PS) 0-1. The EFS was reproducible between visits (r = 0.81 [95%CI 0.64-0.9], p<0.01). No association existed for the EFS and receipt of chemotherapy for the study population as a whole, however none of the stage II patients had features requiring chemotherapy. Restricting the analysis to stage III/IV patients demonstrated a reduced likelihood of receiving chemotherapy with higher EFS scores (Odds ratio 0.56 per unit increment [95%CI 0.37-0.85] p<0.01). A similar effect was observed after multivariate analysis (adjusting for PS, age, stage and gender, Odds ratio 0.41 per unit increment [95%CI 0.18-0.96] p<0.05). The clinician’s qualitative impression was associated with the EFS (p<0.01). No association existed between the EFS and upfront dose reductions, choice of less toxic regimens, or hospitalization secondary to grade 3/4 toxicities. Conclusions: The EFS can identify patients that Oncologists may have thought were too frail for chemotherapy, independent of PS. The EFS has the potential to add a reproducible, and quantifiable measure of frailty to aid in decision making in oncology practice.