Efficacy of the CARG Toxicity Score versus clinician estimate for predicting the risk of chemotherapy toxicity in older adults with cancer.

Intervention: Geriatric assessment and calculation of CARG Toxicity Score. This involves a face-to-face health questionnaire with the participant performed by a study researcher and takes no longer than 30 minutes. Health domains covered as part of the geriatric assessment include functional status, comorbidity, history of falls, cognition, nutrition, psychosocial health and a timed walk test. The geriatric assessment is performed in the outpatient clinic area on one occasion prior to the participant commencing treatment with chemotherapy. The treating oncologist is asked to nominate for each patient their estimate of the likelihood of severe chemotherapy toxicity over the course of treatment, and make an assessment of the patient's clinical frailty status and performance status. For Part 1 of the study, the treating oncologist is not made aware of the results of the geriatric assessment and CARG Toxicity Score, but results are recorded by study researchers. Participants are followed throughout their chemotherapy course to observe for severe chemotherapy-related toxicity and treatment deliverability (unplanned hospital admissions, dose modifications). After target accrual for Part 1 of the study, transition will be made to Part 2, where results of the geriatric assessment and CARG Toxicity Score will be presented to the treating oncologist prior to the patient commencing chemotherapy. The treating oncologist will complete a questionnaire, taking no more than 10 minutes, addressing how useful they found the provided information from the geriatric assessment, if it provided them with new information above their usual clinical assessment, and if they would modify their proposed treatment plan or employ any additional interventions based on the results. The treating oncologist may amend their planned care plan for the patient at their own discretion.