Determinants of informed consent in a cataract surgery clinical trial: why patients participate

To identify the determinants of patients' decision-making for participation in a cataract surgery clinical trial in a tertiary care hospital.

Prospective observational study.

We interviewed by questionnaire 40 patients scheduled to have cataract surgery.

The data collected from patients included attitudes about informed consent, evaluation of the provision of information, and sociodemographic variables.

Overall, 20 (50%) patients consented to enter the trial. All patients (n = 20;100%) in the consenting group expected positive implications compared to 6 (30%) in the nonconsenting group, who expected negative implications (p = 0.008). The majority of patients (90%) in the nonconsenting group felt that the degree of risk incurred by undergoing trial treatment was moderate to high. The perceived burden imposed on daily life by participating was seen by the nonconsenting group to be moderately higher in 11 patients (55%) compared to 3 patients (15%) in the consenting group (p = 0.026). Of the nonconsenting patients, 50% were dissatisfied with the attitudes of medical experiments as compared to 2% of those who did consent (p = 0.023).

The major reasons for participation in a cataract surgery trial were (i) expected positive implications resulting from involvement; and (ii) satisfaction with the attitudes of medical experiments. Patients who refused to enter the trial felt that the degree of risk as well as the burden imposed on daily life by participating were high. Demographic variables did not have any impact on a patients' decisions to accept or decline entry into the trial.