SOCIODEMOGRAPHIC ANALYSIS OF PATIENTS IN RADIATION-THERAPY ONCOLOGY GROUP CLINICAL-TRIALS

Purpose: To assess the degree to which the sociodemographic characteri stics of patients enrolled in Radiation Therapy Oncology Group (RTOG) clinical trails are representative of the general population. Methods and Materials: Sociodemographic data were collected on 4016 patients e ntered in 33 open RTOG studies between July 1991 and June 1994. The da ta analyzed included educational attainment, age, gender, and race. Fo r comparison, we obtained similar data from the U.S. Department of Cen sus. We also compared our RTOG data with Surveillance Epidemiology and End Results (SEER) data for patients who received radiation therapy, to determine how RTOG patients compared with cancer patients in genera l, and with patients with cancers at sites typically treated with radi otherapy. Results: Overall, the sociodemographic characteristics of pa tients entered in RTOG trials were similar to those of the Census data . We found that, in every age group of African-American men and at nea rly every level of educational attainment, the proportion of RTOG tria l participants mirrored the proportion in the census data. Significant differences were noted only in the youngest category of African-Ameri can men, where the RTOG accrues more in the lower educational categori es and fewer with college experience. For African-American women, we f ound a similar pattern in every age group and at each level of educati onal attainment. As with men, RTOG trials accrued a considerably large r proportion of younger, less educated African-American women than the census reported. Using SEER for comparison, the RTOG enrolled proport ionately more African-American men to trials all cancer sites combined , and for prostate and head and neck cancer. In head and neck trials, the RTOG enrolled nearly twice as many African-American men than would be predicted by SEER data. In lung cancer trials, RTOG underrepresent ed African-American men significantly; however, there was no differenc e for brain cancer trials. There were no racial differences in RTOG ac crual and SEER incidence data for women on trials in brain, lung, and head and neck cancer. However, the RTOG trials accrued nearly twice th e proportion of African-American women in cervical cancer trials and i n all sites combined, compared to the SEER data. Conclusions: Comparis ons with the U.S. Census and SEER show that African-Americans are prop ortionally well represented in cancer clinical trials conducted by the Radiation Therapy Oncology Group. The comparative analysis indicates that all educational levels in each age group of African-Americans gen erally mirror the U.S. Census, with one exception. The exception is a significant overrepresentation of less-educated African-Americans in t he youngest age category. This exception is counter to the expectation that better-educated patients are more likely to enroll in trials. Wh en compared with SEER data, the RTOG trials either parallel or overrep resent African-American men and women, with the only exception being i n lung cancer, where men are underrepresented. These results show that , in comparison to the Census and SEER data, the RTOG has fulfilled it s commitment to enroll African-American patients in its clinical trial s. (C) 1998 Elsevier Science Inc.