The influence of political ideology on clinical trial knowledge, invitation, and participation among adults in the United States

BACKGROUND

Clinical trials remain a critical component of medical innovation. Evidence suggests that individuals' political ideologies may impact their health behaviors. However, there is a paucity of literature examining the relationship between political ideologies and clinical trial knowledge and participation.

METHODS

Study data were derived from Health Information National Trends Survey 5 Cycle 4 (n = 3300), which was conducted from February to June 2020. We used participants' characteristics to estimate the prevalence of clinical trial knowledge and participation. We used multivariable logistic regressions to investigate whether political ideology had a significant impact on clinical trial knowledge and participation. Jack-knife replicate weights were applied for population-level estimates.

RESULTS

Most participants were White (64.2%), earned above US$50,000 (62.4%), and lived in urban areas (88.0%). About 59.2% reported having some knowledge of clinical trials, and only 8.9% had ever been invited to participate in clinical trials. A total of 37.0%, 29.5%, and 33.5% of the population endorsed moderate, liberal, and conservative political viewpoints respectively. In the adjusted logistic regression analysis, compared to conservatives, liberals (adjusted odds ratio, 1.92; 95% confidence interval, 1.31-2.80) and moderates (adjusted odds ratio, 1.43; 95% confidence interval, 1.09-1.88) had significantly greater odds of having knowledge of clinical trials. Also, liberals had higher odds of receiving invitations to participate in clinical trials (odds ratio, 1.76; 95% confidence interval, 1.08-2.85; p = 0.023) and greater odds of trial participation (odds ratio, 3.90; 95% confidence interval, 1.47-10.33; p = 0.007) compared to moderates.

CONCLUSIONS

The mechanism underlying the higher rates of clinical trial invitations to liberals is unclear and requires further comprehensive investigation. Similarly, further qualitative studies are needed to understand the attributes that promote knowledge and increased likelihood of clinical trial participation among liberals. This will provide crucial insight to help design interventions that further involve conservatives and moderates in clinical trials and scientific enterprise.

adults aged 65 years and up: Findings from a 2020 national survey

BACKGROUND

Older adults are underrepresented in most clinical trials. As the United States observes growth in the number of older adults over time, it will be critical to include them in clinical trials to improve the generalizability of results across age groups. Although clinical trial participation requires clinical trial knowledge, no study has assessed clinical trial knowledge among older adults. Using a national survey, this study aims to identify the prevalence and determinants of clinical trial knowledge among older adults.

METHODS

We used the 2020 Health Information National Trends Survey for secondary data analysis. We restricted the sample to older adults (aged 65 years and up). Our outcome variable was whether respondents reported having any clinical trial knowledge. We controlled for demographics, social determinants of health, healthcare utilization, and comorbidities through multivariable logistic regression models.

RESULTS

Using a weighted sample of 27,574,958 adults, we estimated that 61.1% of older adults reported having at least some knowledge of clinical trials. After controlling for other factors, those with one to two (OR = 1.80, 95% CI:1.14-2.84) or three to five (OR = 2.93, 95% CI:1.74-4.95) portal visits compared with no portal visits, those with cancer (OR = 1.92, 95% CI:1.22-3.02), and those with depression (OR = 2.27, 95% CI:1.23-4.20) had greater odds of having clinical trial knowledge. Inversely, those with hypertension (OR = 0.62, 95% CI:0.42-0.92) had lower odds of clinical trial knowledge.

CONCLUSIONS

Patient portal recruitment may be a supplemental intervention to improve clinical trial knowledge among older adults. Further research on additional interventions for identifying eligible participants is needed to minimize the burden among clinicians amidst other competing demands during clinic visits.

Development and Evaluation of the Clinical Trial HEalth Knowledge and Beliefs Scale (CHEKS)

Patient health literacy is vital to clinical trial engagement. Knowledge and beliefs about clinical trials may contribute to patient literacy of clinical trials, influencing engagement, enrollment and retention. We developed and assessed a survey that measures clinical trial health knowledge and beliefs, known as the Clinical trial HEalth Knowledge and belief Scale (CHEKS). The 31 survey items in CHEKS represent knowledge and beliefs about clinical trial research (n = 409) in 2017. We examined item-scale correlations for the 31 items, eliminated items with item-scale correlations less than 0.30, and then estimated internal consistency reliability for the remaining 25 items. We used the comparative fit index (CFI) and the root mean squared error of approximation (RMSEA) to evaluate model fit. The average age of the sample was 34 (SD = 15.7) and 48% female. We identified 6 of the 31 items that had item-scale correlations (corrected for overlap) lower than 0.30. Coefficient alpha for the remaining 25 items was 0.93 A one-factor categorical confirmatory factor analytic model with 16 correlated errors was not statistically significant (chi-square = 10011.994, df = 300, p < 0.001) but fit the data well (CFI = 0.95 and RMSEA = 0.07). CHEKS can assess clinical trial knowledge and beliefs.