Understanding of Clinical Trials Among Patients With Cancer and Their Relatives.

Importance: Clinical trials are vital for advancing cancer treatments and improving patient outcomes. Understanding the factors that influence participants' decision-making is critical for enhancing trial recruitment. Objective: To evaluate the attitudes of patients with cancer and their relatives toward clinical trial participation, identifying key barriers and motivators that affect their willingness to engage in such trials. Design, Setting, and Participants: This cross-sectional survey study was conducted between April 2020 and April 2021. Face-to-face questionnaires were administered by physicians across 6 tertiary hospital medical oncology departments in Turkey. Adults with cancer and their relatives were recruited. Data were analyzed from April to December 2021. Exposure: Participants' knowledge, perceptions, and motivations regarding clinical trial participation were assessed through a structured questionnaire. Main Outcomes and Measures: Participants' demographic information, their willingness to participate in clinical trials, their perceptions about the clinical trial participation, and the facilitators and barriers to participation. Results: A total of 978 participants were surveyed, with a median (range) age of 52 (18-82) years; 485 (49.6%) were male and 479 (49.0%) female. Of these, 578 (59.1%) were patients with cancer and 382 (39.1%) family members. Prior clinical trial experience was reported by 174 participants (17.8%), and 428 (43.8%) expressed a willingness to participate in clinical trials. Participants well-informed about clinical trials showed higher willingness (50 of 87 [57.5%] very willing) compared with those with no knowledge (27 of 303 [8.9%] very willing) (χ2 = 275.095; P < .001). Greater willingness was observed in participants from less developed cities compared with the most developed cities (88 of 321 [27.4%] vs 94 of 615 [15.3%]; χ2 = 21.093; P < .001), in individuals with a high school degree or greater compared with those with less than a high school degree (105 of 489 [21.5%] vs 76 of 452 [16.8%]; χ2 = 33.311; P < .001), in those with monthly incomes above compared with below the poverty line (81 of 409 [19.8%] vs 100 of 512 [19.5%]; χ2 = 16.145; P = .003), in those without prior cancer treatment compared with those with prior cancer treatment (125 of 591 [21.2%] vs 40 of 289 [13.8%]; χ2 = 13.801; P = .008), and in participants with prior trial experience compared with those without (74 of 166 [44.6%] vs 111 of 786 [14.1%]; χ2 = 87.771; P < .001). Participants were motivated by potential personal health benefits (604 [61.8%]) and access to new treatments (522 [53.4%]). The primary concerns included potential adverse effects (555 [56.7%]), feeling like a "test subject" (284 [29.0%]), and the risk of receiving a placebo (197 [20.1%]). Conclusions and Relevance: In this survey study of patients with cancer and their relatives, significant gaps in knowledge and persistent concerns about clinical trial safety were highlighted, impacting participation. Addressing these concerns through targeted education and transparent communication is essential for improving participation rates and ensuring more inclusive cancer research.