Elements of informed consent and decision quality were poorly correlated in informed consent documents

Although informed consent (IC) documents must contain specific elements, inclusion of these elements may be insufficient to encourage high-quality decision making. We assessed the extent to which documents conform to IC standards and how well conformity to decision quality (DQ) standards can be predicted by IC standards, IC document characteristics, and study characteristics.

We obtained 139 IC documents for trials registered with ClinicalTrials.gov from study investigators. Using a four-point scale, two raters independently assessed each IC document on 36 IC standard items and 9 DQ items.

Overall agreement between raters across all 45 items was 93%. Across the 36 IC standards items, conformity was generally quite high but variable, with 20 items showing conformity of 80% or more and seven items showing conformity of 50% or lower. IC standards concordance, overall length of the IC document, and country of study were all significant predictors of DQ standards but together accounted for less than 20% of the variance in DQ standards.

Conformity to recommendations for improving IC documents was relatively high but variable. The extent to which an IC document conformed to these recommendations was only moderately related to whether it conformed to recommendations for improving DQ. Existing IC regulations may not describe the optimal approach to helping people make good study participation decisions.