What is the best method to ensure informed consent is valid for orthodontic treatment? A trial to assess long-term recall and comprehension

Abstract

Design Single-blind randomised controlled trial.

Intervention Patient and parent pairs were randomly assigned via a random number generator to Group A or B. Both groups were given ten minutes to read a modified consent document. Group A (rehearsal) were given printouts that showed images of four core and four custom risks with handwritten descriptions of each risk and consequences. Group B were given an audio-visual presentation instead (PowerPoint). Interviews of each group were completed immediately after the informed consent and at six-month follow-up to assess recall and comprehension of information provided.

Case selection Patients aged 11-18 years old and their parents attending for comprehensive orthodontic treatment at Ohio State University graduate orthodontic clinic. All subjects needed to be able to communicate in English, have no developmental disabilities or urgent medical conditions and neither the patients or parents or subjects' siblings were to have had orthodontic treatment in the last five years.

Data analysis 1) Exploratory analysis to test for differences in demographics and anxiety between the two groups; 2) Multiple linear regression analysis was used to assess percentage of accurate responses at baseline and six months and the change between the two different groups, with differing baseline characteristics (p <0.05 was considered statistically significant); and 3) Intra- and inter-rater reliability was assessed using intra-class correlation.

Results There were no significant differences in information retention and understanding between the two methods at six-month follow-up. For both groups, recall was significantly lower six months following consent-taking. Specific domains whereby information recall and comprehension are poor include: treatment method, risks, resorption and discomfort.

Conclusions There is no superior method of consent-taking to ensure patients' and parents' information retention in the months following commencement of treatment. However, the study highlighted that current consent practices which are considered 'best practice' may be deficient.