Process of conducting a human factors validation study and the requirements
As Mary Beth Privitera stated on the most recent edition of the hsDNA podcast, this is one human factors methodology where the agency has done a really good job of communicating what their expectations are. It is also the one method that has some significant rules that must be adhered to in order to have an adequate validation test. The test runs like the other human factors studies where you are going to generate a protocol, you're going to go through the logistics, conduct testing, conduct the root cause analysis and report.
That said, there are some specific requirements that have to be included. For example, if it was a product that was intended to be used by pediatric users and adults, then you'd have 15 pediatric users and 15 adult users that would be in the test. You have to have the final product. The final product must be functional. It must be representative of what's going to go out into the field.
As Mary Beth points out, "The one difference between a validation test, which is also sometimes called a summative versus a formative test are that in a formative test, you don't have a lot of those rules. You can do a little, there's a little bit more wiggle room, but in the validation test, you've got to adhere by strict rules."
"Another strict rule that I didn't mention in the book which is important is that as a human factors evaluator, I cannot interact or assist the user unless I record that I did. It's sort of, I want to be a fly on the wall during this test and let them just use the device and then watch them. Then when they become challenged, I prompt them to say, what would you do if this was a real case? Then eventually, I can intercept or intervene, but I have to mark that and note that. Oftentimes when you do intervene, then that becomes a use error and that gets noted. It's definitely a process that is got a little bit more control to it that must be adhered to."
