During the past two decades, various ways of measuring assertiveness have been attempted. Researchers found multiple factors more consistent with state theory. The measurement of assertion has been attempted through testing knowledge, behavioural assessment, and self-report. The testing of knowledge suggests that the level of knowledge is correlated with application, in that, those who know more about assertiveness will behave in a more assertive manner. There is, in fact, little support for this idea, and reliability and validity instruments for testing knowledge have not been established.
Instruments designed to measure assertiveness are numerous and varied.
Some instruments measure assertiveness as a subscale within a tool measuring a larger concept, such as population, role, or set specific measures, and often span the ages from child to adult. Other instruments measure assertiveness as a primary concept, of which two specify nurses. Expressions of rights and feelings. Initiating, maintaining, and terminating conversations. The effects of training on specific populations of patients, health professionals and students.