Background: Family caregivers play an increasing role in cancer treatment decision-making. We examined bias reported by family caregivers in the support they and their patient received from their healthcare team when making these decisions, including associations with distress.

Methods: Analysis of 2021 national survey data of family caregivers of patients with cancer (N = 2703). Bias experienced in decision support was assessed with the item: "Have you felt that the support you and the person with cancer have received for making cancer-related decisions by your doctor or healthcare team has been negatively affected by any of the following?" Check-all-that-apply response options included: age, race, language, education, political affiliation, body weight, insurance type or lack of insurance, income, religion, sexual orientation, and gender/sex. Chi-square and regression analyses assessed associations between bias and caregiver distress (GAD-2, PHQ-2).

Results: Of 2703 caregiver respondents, 47.4% (n = 1281) reported experiencing ≥1 bias(es) when receiving decision support for making cancer-related decisions. Bias was more prevalent among younger caregivers, males, transwomen/men or gender non-conforming caregivers, racial/ethnic minorities, and those providing care over a longer time period. The odds of having high anxiety (GAD-2 scores ≥ 3) were 2.1 times higher for caregivers experiencing one type of bias (adjusted OR, 2.1; 95% CI, 1.6-2.8) and 4.2 times higher for caregivers experiencing ≥2 biases (adjusted OR, 4.2; 95% CI, 3.4-5.3) compared to none. Similar results were found for high depression scores (PHQ-2 scores ≥ 3).

Conclusions: Nearly half of caregivers involved in their care recipients' cancer-related decisions report bias in decision support received from the healthcare team. Experiencing bias was strongly associated with high psychological distress.