While race and gender are often mentioned as factors complicating efforts to ensure clinical trials are conducted in representative populations, new research suggests that similar distinctions may apply to the personnel managing a clinical study.

A team from the University of Cincinnati in Ohio, US found, for example, that black patients – both male and female – were around 15% less likely than white patients to be willing to take part in research when approached by a white male Clinical Study Assistant (CSA).

However, black patients were about 15% more likely to agree to participate when approached by a white female assistant.

On the other hand, black patients were roughly 50% less likely than white patients to be willing to take part in research when approached by a black female study assistant.

The analysis, which was presented at the Society for Academic Emergency Medicine’s annual meeting in Atlanta, US, built on previous research at the University of Cincinnati showing that black and female patients were less likely to agree to participate in research, despite being offered more frequent opportunities to do so.

Complex relationship

The outcomes of the latest study suggest that relationships between the gender and race of patients and study personnel in these circumstances are anything but black and white.

“We found that willingness to participate in research is influenced by the race and sex of the study assistant, but the impact is different for different groups,” commented lead author Kimberly Hart, a research associate in the University of Cincinnati’s department of emergency medicine.

“As researchers, we should be aware of the impact of race and sex on our relationships with study participants. The relationship is much more complicated than we thought it would be, and we hope to conduct further research to better understand the reasons behind our observations.”

The researchers hypothesised that when a patient were approached by a study assistant of the same race or gender, that patient would be more willing to participate in a trial than when race and gender were different.

“Social theories about relationships between medical providers or researchers and patients suggest that patients may have more trust in providers who are similar to them in terms of gender and race, but there are few research studies that directly address race and sex differences between medical researchers and patient participants,” Hart pointed out.

Study cohort

The University of Cincinnati (UC) team looked at nearly 160,000 patients screened for clinical research by 89 different study assistants at the UC Medical Center emergency department and the Jewish Hospital emergency department between January 2007 and December 2011.

Patients were screened by Clinical Study Assistants, and their willingness to be approached for research if eligible was documented along with patient demographics.

Logistic regression was used to determine whether the race and sex of the CSAs affected the odds of willingness to participate in research among black and white patients, and among male and female patients.

The patient population studied was 60% white and 44% male, while the study assistants were 75% white and 44% male. A large majority – 89% – of patients were willing to be approached for clinical-research participation.