Parental consent to participation in a randomised trial in children: associated child, family, and physician factors.

BACKGROUND

Low participation rates in randomised controlled trials involving children are almost a universal problem, leading to high cost and low statistical power. Trial, parent/family, child, and physician factors have been reported to influence parental willingness to consent for paediatric trials.

PURPOSE: To identify modifiable and unmodifiable factors associated with parental consent.

METHODS

Demographic and clinical characteristics of children and their families and physician characteristics associated with parental consent were evaluated in a recent randomised placebo-controlled trial of prophylactic antibiotics to prevent recurrent urinary tract infection.

RESULTS

Of 1109 eligible children identified (mean age, 2.0 years), 412 parents (37.2%) consented. On a multivariate analysis, the only modifiable factor associated with consent was request for consent by a member of the research study team rather than by a member of the clinical team (risk ratio (RR) = 1.9, 95% confidence interval (CI): 1.2-2.9). The unmodifiable factors significantly associated with consent were age of the child (≥4 years) (RR = 1.2, 95% CI: 1.1-1.4), presence of vesicoureteric reflux (RR = 1.5, 95% CI: 1.3-1.8), inpatient management of the index infection (RR = 0.8, 95% CI: 0.7-0.9), and multiple (≥4) symptoms at presentation (RR = 1.3, 95% CI: 1.1-1.5).

LIMITATIONS: We have reported data from only one of the four participating centres in this trial. Data on non-consenters in other participating centres were not completely collected. Data on characteristics of the recruiting physician were limited. These findings are applicable for those considering a single randomised controlled trial.

CONCLUSIONS

Parent, child, and physician factors are associated with consent for trial participation, with most not being modifiable. Having a member of the research study team approach the parent for consent appears to be the only feasible strategy for increasing recruitment to randomised trials in this setting.