Randomized Controlled Trial
A trial in which subjects are randomized to different groups (control and intervention) for the purpose of studying the impact of different training methods / models.

Blinded / Nonblinded
This term refers to the knowledge of evaluators in educational studies with respect to the intervention status or level of training of the participants.

Pretest / Posttest
In these studies subjects are assessed prior to and following a training intervention.

Cohort Study
Studies in which the outcomes in a group of subjects that underwent an intervention are compared with those in a similar group that did not. In educational research this is primarily used to demonstrate construct validity or to compare the impact of different teaching methods.

Validation Study
The primary goal of these studies is to demonstrate validity of an assessment tool or a training model.

Reliability Study
The primary goal of these studies is to demonstrate reliability of an assessment tool or a training model (or exam).

Observational Study
This involves observing one or more subjects performing a task with the intention of describing or comparing particular aspects of their performance.

Descriptive Study
Such studies report on performance and behaviors observed during the course of an intervention, often providing details of that intervention, without attempting to objectively evaluate outcomes.