Joseph M. Unger, MS, PhC, a health services researcher and statistician with the SWOG Statistical Center at the Fred Hutchinson Cancer Research Center in Seattle, Washington, discusses an online survey of 5,499 patients with cancer that examined the effects of socioeconomic and demographic factors on clinical trial participation.

The trial adjusted for all socioeconomic and demographic factors, including income, education, age, race, sex, and other factors such as distance from center, which was used as a measure of convenience, and the patient's medical condition. Overall, the trial found that income was the only socioeconomic status or demographic factor that was an independent predictor of clinical trial participation.

Cancer patients with a lower annual household income, defined as less than $50,000 a year, were 30% less likely to participate in clinical trials. Unger notes that these findings seem to be independent of how income was categorized. Primarily, the reason for less participation in the trial was tied to concerns over how to pay for the trial.

This finding has distinct implications for patients and raises the issue of whether patients of all income levels have equal access to clinical trials. Additionally, Unger notes, for researchers it shows the need to increase participation for lower income patients, which could substantially increase clinical trial participation, allowing for faster completion, and would better ensure applicability across all income brackets.