Readability of informed consent documents and its impact on consent refusal rate

Informed consent documents (ICDs) are integral to a research project and must provide all required information to the participant. We undertook a 6-year retrospective cross-sectional analysis of ICDs to assess the same. We accessed 300 ICDs from studies submitted to institutional ethics committee. Studies were selected using random proportional-to-size sampling across years and study types (thesis, pharma, government, investigator initiated [OA] studies). We used the Flesch-Kincaid Reading Ease Score (FRES), estimated reading time (ERT) and scored ICDs out of 13 points on the basis of the Indian Council of Medical Research (ICMR)-mandated headings (ICD Quality Score [IQS]). Information pertaining to the consent refusal rate (CRR) of each study was correlated with FRES, ERT, and other parameters. P <0.05 was considered statistically significant. Two hundred and ninety-three ICDs had complete information. Median FRES was 48.3 (interquartile range [IQR] = 7), median ERT was 4.5 min (IQR = 1.3), the median expected duration of participation was 35 min (IQR = 40); compensation was provided by 23 projects and median compensation was Rs. 2500 (IQR = Rs. 4750). Mean IQS improved from 11.95 to 12.60 in 6 years (Kruskal-Wallis test, P < 0.001). FRES was weakly negatively correlated to the CRR (r = -0.120, P = 0.039), while the expected duration of participation was weakly positively correlated (r = 0.144, P = 0.014). Pharma studies performed better and ICDs have improved in their readability and ICMR guidelines compliance.