Clinical tools for oncology professionals

CARG score

Predicts risk of severe chemotherapy toxicity (grade 3-5) in older patients aged over 65.






Serum creatinine

Creatinine clearance*:
*Jelliffe equation


Cancer type

Gastrointestinal 2 points
Genitourinary 2 points
Any other 0 points

Chemotherapy dosage

Standard dosing 2 points
Reduced dosing 0 points

Number of chemotherapy drugs

Poly-chemotherapy 2 points
Mono-chemotherapy 0 points

How is your hearing (with a hearing aid, if required)?

Totally deaf 2 points
Poor 2 points
Fair 2 points
Good 0 points
Excellent 0 points

Number of falls in the past 6 months

1 or more 3 points
None 0 points

Can you take your own medicines?

Completely unable 1 points
With some help (able to take if someone prepares it for you and/or tells you to take it 1 points
Without help (in the right doses and at the right times) 0 points

Does your health limit you in walking one block?

Limited a lot 2 points
Limited a little 2 points
Not limited at all 0 points

During the past 4 weeks, how much of the time has your physical health or emotional problems interfered with your social activities (like visiting friends, relatives, etc)?

All of the time 1 points
Most of the time 1 points
Some of the time 1 points
A little of the time 0 points
None of the time 0 points

CARG score: Predicting chemotherapy toxicity in older adults

Risk category CARG score Number of patients G3-5 toxicity risk (%)
Low 0-5 128 30
Medium 6-9 227 52
High 10-19 109 83

  • The CARG score is a predictive model developed to identify older patients (aged > 65) at increased risk of severe (grade 3-5) chemotherapy toxicity.
  • The model was developed using data from a multi-centre prospective study of 500 cancer patients aged 65 years or older scheduled to receive chemotherapy. The model was internally validated using a ten-fold cross validation process.
  • 3 risk categories were established, identifying patients at low, medium and high risk of toxicity (see table above).
  • The CARG score has been externally validated in a number of external studies and found to display moderate ability to predict chemotherapy toxicity (2–4). In these studies the model performance, as measured by receiver operator characteristic area under the curve (ROC-AUC), was reported as 0.65, 0.68 and 0.76.
  • ASCO guidelines for geriatric oncology(5) recommend the use of either the CARG or CRASH score in predicting chemotherapy toxicity in patients aged over 65.


  1. Hurria A, Togawa K, Mohile SG, et al. Predicting chemotherapy toxicity in older adults with cancer: a prospective multicenter study. J Clin Oncol Off J Am Soc Clin Oncol. 2011;29(25):3457-3465. doi:10.1200/JCO.2011.34.7625
  2. Ortland I, Mendel Ott M, Kowar M, et al. Comparing the performance of the CARG and the CRASH score for predicting toxicity in older patients with cancer. J Geriatr Oncol. 2020;11(6):997-1005. doi:
  3. Zhang J, Liao X, Feng J, Yin T, Liang Y. Prospective comparison of the value of CRASH and CARG toxicity scores in predicting chemotherapy toxicity in geriatric oncology. Oncol Lett. 2019;18(5):4947-4955. doi:10.3892/ol.2019.10840
  4. Hurria A, Mohile S, Gajra A, et al. Validation of a Prediction Tool for Chemotherapy Toxicity in Older Adults With Cancer. J Clin Oncol Off J Am Soc Clin Oncol. 2016;34(20):2366-2371. doi:10.1200/JCO.2015.65.4327
  5. Mohile SG, Dale W, Somerfield MR, et al. Practical Assessment and Management of Vulnerabilities in Older Patients Receiving Chemotherapy: ASCO Guideline for Geriatric Oncology. J Clin Oncol. 2018;36(22):2326-2347.