Background: "Head CT Choice", a decision aid (DA) that facilitates shared decision-making in parents of children with minor head trauma, was shown in a multicenter trial to increase parent knowledge, increase physician trust and decrease 7-day healthcare utilization. Based on findings from a previous multicenter shared decision-making trial in adults with chest pain, we tested the hypothesis that the DA would be similarly effective across all subgroups but increase knowledge more in parents with higher numeracy and physician trust more in parents with low health literacy.
Methods: We performed a secondary analysis of a randomized trial conducted at 7 U.S. emergency departments. One hundred seventy-two clinicians caring for 971 children at intermediate risk for clinically important traumatic brain injuries according to the Pediatric Emergency Care Applied Research Network (PECARN) prediction rules were cluster randomized to always use the DA (n=493) or to always use their usual practice (n=478). We assessed for subgroup effects based on the child’s age, sex, race, and PECARN risk factors and the parent’s education, numeracy, and health literacy. We dichotomized each characteristic and tested each for interaction with trial outcomes using regression models that included study site as a covariate.
Results: The DA was similarly effective across all subgroups but did not differentially increase knowledge in parents with higher numeracy (P for interaction = 0.14) or physician trust in parents with low health literacy (P = 0.34). The DA decreased decisional conflict more in non-white parents (decisional conflict scale, -8.1, 95% CI ‑12.3 to -4.0; P = 0.05), decreased the odds of cranial computed tomography (CT) use in parents with low health literacy (OR 0.36, 95% CI 0.16-0.83, P = 0.01) and increased the odds of CT use in children younger than 2 years-old (OR 1.94, 95% CI 0.95-3.97, P = 0.02).
Conclusion: Use of the Head CT Choice DA decreased decisional conflict and the odds of CT in non-white minority parents. Tailoring shared decision-making to parent/patient characteristics may be necessary to maximize effectiveness in children.