Background: Information leaflets in research studies should be age-appropriate to be understood, however the formal readability of children's participant information leaflets (PILs) for research studies has not been assessed.

Methods: A single-centre cross-sectional study assessing paediatric PILs. Six readability tests were applied (Gunning Fog Index (GFI), Simple Measure of Gobbledygook (SMOG), Flesch Kincaid Grade Level (FKGL), Coleman-Liau Index (CLI), Automated Readability Index (ARI) and Flesch Reading Ease score (FRE). Results were compared between age groups, and whether the PIL was from either a commercially sponsored or investigator led study.

Results: 191 paediatric PILs were included. Age categories; <10 years (n = 65), ≤12 (n = 73), ≤15 (n = 73) and ≥16 (n = 61); were used for analysis. There were 39 commercial PILs and 226 non-commercial PILs. For the ≤10 and ≤12 age bands, all 6 median readability scores exceeded the target age group (thus hard to read, p < 0.005), and there was no difference in readability scores between these two age bands. Four scores from the readability tests were considered age-appropriate in the ≤15 year category, and all median scores were age-appropriate in the ≥16 years age groups. Readability scores for children's PILs were significantly higher in commercially sponsored versus non-commercial studies (P < 0.005).

Conclusion: Improvements are required to make children's PILs readable for the target audience, particularly in commercially sponsored research studies.

Impact: Paediatric participant information leaflets may not be readable in research studies, especially in younger age groups. PILs for children participating in commercially sponsored studies were less readable than non-commercial studies. Research teams writing PILs for a paediatric study need to consider the use of readability tools to ensure that the information they are providing is readable by the target audience.

Competing interests: The authors declare no competing interests.

👁 Fig. 1

Fig. 1. Boxplot of SMOG readability score…

Fig. 1. Boxplot of SMOG readability score for paediatric PIL’s assessed within the specified age…