Assessing comprehension of clinical research.

Background: Comprehension and retention of study-related concepts by research subjects are understudied, particularly in certain areas of women's health such as menopausal hormone therapy (MHT).

Methods: In a multi-center trial of MHT, a 9-item participant comprehension questionnaire (PCQ) tested knowledge of key concerns relating to MHT at two study sites. The PCQ was administered at baseline. At study site1, PCQ was re-administered to assess information retention months later. Multivariable analyses assessed predictors of participant comprehension after adjusting for age, race, education, annual family income (AFI), menopausal symptoms and study site.

Results: 151 participants (n = 89 at site I, n = 62 at site II) completed the PCQ at baseline; 71 participants from site I completed the follow-up PCQ. Participant comprehension at baseline was influenced by age, marital status, education, symptom of dyspareunia, season of enrollment and AFI<$40,000. Significant improvement in correct responses was observed at follow-up compared to baseline (p = 0.02); season and low AFI<$20,000 were predictive of likelihood for correctly answering <5/9 at follow up.

Conclusion: Assessing participant comprehension of research-related concepts using a PCQ identifies a need for ongoing reinforcement of relevant details, especially in symptomatic early menopausal women of lower education and income. Improved participant comprehension at follow up is reassuring and reflects success of the research team in communicating study-related concepts to participants enrolled in longitudinal studies.