Performance of the University of California, San Diego Brief Assessment of Capacity to Consent (UBACC) questionnaire in mental health genetic research in Africa.

IMPORTANCE

Over the last decade, there has been an increase in genetic research on mental health conditions the world over including in Africa. It remains unknown whether individuals who consent to participate in genetics research understand the context, the risks and benefits of their involvement in the research and most importantly the concept of voluntary participation.

OBJECTIVE

The University of California, San Diego Brief Assessment of Capacity to Consent questionnaire (UBACC) can assess decisional capacity during the consent process. We set out to assess how well the UBACC could improve the consent process in the largest genetics study in Africa.

METHODS

This cross-sectional study was conducted from 2018 to 2022 across multiple sites in Ethiopia, Kenya, South Africa and Uganda. Participants were recruited from mental health facilities and general outpatient clinics. Participants were adults aged at least 18 years, half of whom had a diagnosis of psychosis (cases) and the other half did not (controls).

INTERVENTION: For each potential participant, research assistants read participant information sheets and informed consent materials out loud and then asked them questions about the study. This was repeated up to three times for participants who scored less than the maximum score of 20. We calculated the mean scores at attempts 1–4 and conducted regression post hoc analyses to determine the socio-demographic factors associated with a maximal score of 20.

RESULTS

Of the 42 953 participants, 57.35% were male. The mean age of participants was 36.69 (SD=11.7). The mean UBACC score improved significantly across attempts, rising from 13.27 (SD±3.5) at attempt 1 to 16.83 (SD±3.0) at attempt 2, 18.10 (SD±2.2) at attempt 3 and 18.37 (SD±1.6) at attempt 4, with each score significantly higher than the previous one. Male sex was associated with increased odds of achieving a UBACC score of 20 (OR=1.35, 95% CI 1.28 to 1.40), whereas being a case was associated with lower odds of reaching this score (OR=0.59, 95% CI 0.56 to 0.61). Lower age was associated with modestly lower odds of scoring 20 (OR=0.99, 95% CI 0.98 to 0.99), while higher education was associated with substantially higher odds of reaching this score (OR=2.69, 95% CI 2.24 to 3.22).

CONCLUSION AND RELEVANCE: The association of specific socio-demographic variables with maximal UBACC scores is consistent with expectations. An iterative process using the UBACC facilitates informed consent in mental health genetics studies in the African context.

PATIENT INVOLVEMENT: The cross-sectional study was part of a large genetics study where cases and controls were compared across a number of study variables. However, patients and members of the public were not involved in the design of the study.