Table 1.

Summary of main findings, with examples

Category	Factor	Example
Context	Access	Age influences how fast patients are referred to specialized care
	Incidence	Strong association between increasing age and increasing incidence rates for cancer
	Research	Participants in clinical trials often younger than actual disease population
	Screening	Strict age cut-offs for inclusion in public screening programs
	Guidelines	Clinical guidelines use age thresholds when recommending treatment
Patient	Physiology	Age-related declines in CYP enzymes responsible for hepatic drug metabolism
	Tumor biology	Proportion of ER and HER2 status in breast cancer varies between age groups
	Comorbidity	Association between increasing age and increasing number of comorbidities
	Receptivity	Physicians’ recommendations are more influential for older patients
Intervention	Quality	Older patients tend to receive substandard treatment
	Prediction	Risk prediction tools use age for estimations
	Treatment outcome	High age is often a predictor of decreased survival