Table 3.

Final multiple regression model with “overall research participant experience” as the outcome

Items included in model*	R 2	Adjusted R 2 for each additional question in the model**
Treated with courtesy and respect by the investigator or research doctor	0.816	0.809
Prepared for what happened by information and discussions provided before participation	0.896	0.888
Research doctor or investigator listened carefully	0.939	0.932
Prepared for what to expect by informed consent documents	0.950	0.942
Knew how to reach research team	0.961	0.953
Able to reach member of research team when needed	0.968	0.959

*Item phrases summarize the content of the question and not its exact wording in the questionnaire.

**Adjusted R ² serves as an indicator of the ability of a subset of items in the questionnaire to explain overall research participant experiences (Adjusted R ²‐ 0.959; F‐ 4.44; p < 0.046).