Factors influencing inclusion of patients with malignancies in clinical trials

Abstract

Participation in clinical trials remains low and is a central issue in oncology. The authors identified, through a systematic review, 75 papers published up to August 2004 that report barriers to recruitment of patients in clinical trials. These barriers range from patient preference and concern about information/consent to clinical problems with protocols. Strategies to overcome barriers on the part of patients and clinicians are needed and should be carefully evaluated. Thirty-three (44%) papers reported factors related to patients as influencing the inclusion of patients, 28 (37%) reported clinician's related factors, and 37 (49%) other factors from either specific groups of patients (30 papers, 40%) and/or other scopes (13 papers, 17%). No differences in prevalence were found between papers dedicated to hematologic malignancies and solid tumors. Factors related to clinicians as influential were more frequently reported before 1995 (70%) than thereafter (25%; P = 0.0009). Reporting specific groups of patients as influential was more frequent in North American articles (50%) than in others (14%, P = 0.008). Patients' barriers included mostly patient preference (12 papers), concern about information and/or consent (11 papers), worry about uncertainty (7 papers), and/or relationship with medical team (7 papers). Concerning clinicians, incompatibility of protocol with normal practice (nine papers), problems in complying with the protocol (eight papers), and/or consent procedure (eight papers) were the most reported factors. The remaining factors mostly relied on specific groups of patients (30 papers), notably age of patients (18 papers) and/or minority population (11 papers, all from the USA). Strategies to overcome these barriers are needed and should be carefully evaluated.

Oncologists’ recommendations of clinical trial participation to patients

“…One caveat is that the trend toward a gender bias may have been an indirect effect of having more breast and gynecologic studies open for accrual during the period of our data collection. Nevertheless, increasing participation by cancer patients representative of the diverse American population has been identified as a national research goal, in light of evidence demonstrating the under-representation of specific populations in cancer clinical trials [4,[28][29][30][31]. This study was limited to a small and rather homogeneous sample, but even evidence of a trend toward recommending trials to some patient subgroups and not others warrants extending this research to a more diverse population.…”

“…Researchers and clinicians generally agree on several points regarding patient participation in clinical trials: First, clinical trials are the primary mechanism for evaluating the safety and efficacy of new cancer treatments and improving the standard of care [1]; second, meaningful informed consent is a precondition for the ethical involvement of humans in clinical research [1][2][3]; and third, physician communication during clinical encounters is an important factor in patients' decisions about whether to participate in a clinical trial [4][5][6].…”

Early Phase Clinical Trials: Referral Barriers and Promoters among Physicians

“…As expected, those who referred patients were more familiar with clinical trials in their area than those who did not refer patients (88.2% vs. 77.3%, p<0.001). Table 2 shows the dimensions identified through exploratory factor analysis for promoter and barrier items included in the original survey as well as the stand-alone items that were not associated with any of the dimensions but were included in subsequent analysis given that literature suggests their association with referring patients to clinical trials [9,[12][13][14]17,23,36].…”

“…Physicians act as gatekeepers and provide a majority of patient education regarding clinical trials; therefore, they influence recruitment and patient decision-making. Research has shown that participation and recruitment barriers include physicians' lack of clinical trial awareness, attitudes, level of comfort explaining the trial, fear of losing patients, mistrust of medical institutions and researchers, lack of time and structural support, limited resources for data management, complexity of the study protocol and level of burden, feelings about the patient's age and comorbid conditions, and lack of adequate compensation for involvement [1,2,[8][9][10][11][12][13][14][15][16][17][18][19][20]. Physicians may also feel that referring patients to trials might negatively affect and threaten their relationship with patients, manifesting in patients either blaming the physician for any negative consequences of study participation or threatening the physician's income as patients seek increasing care via trial physicians [17,[21][22][23].…”

A Pilot Study of a Culturally Targeted Video Intervention to Increase Participation of African American Patients in Cancer Clinical Trials

“…African Americans (AA) continue to display the lowest 5-year cancer survival rates compared with all other ethnic groups and experience mortality rates approximately 25% higher than whites [2, 4,5]. Of all U.S. adults diagnosed with cancer, an estimated 5%-10% will actually participate in a therapeutic clinical trial [6 -9] and a significantly smaller proportion of those are eligible AA [8,10,11]. A greater burden of disease among AA necessitates their participation in clinical trials, as only sufficient representation will determine whether treatments are equally efficacious [9,[11][12][13][14].…”