4.3 When is Informed Consent Valid?

Just getting people to say ‘yes’ to participation is rarely enough. The consent must also be of a sufficiently high quality: it must be valid.

Informed consent is valid if the prospective research participant:

1. is provided with adequate information and an opportunity to ask questions;
2. has mental competence to understand and retain this information;
3. is making the decision voluntarily (i.e. not as a result of coercion, manipulation, or undue inducements).

This seems to be simple and intuitive, but in reality it is a bit more complex. E.g., how much information is enough, or how much information is too much? Is it ethical to pay (or not to pay) research participants? Read the following text that explains these crucial conditions in some detail.