Middle-range theories often have evidence that is acquired by using many repetitions under controlled conditions (scientific method). An example is Johnson's20 and 21 self-regulation theory that addresses the use of preparatory information to assist persons in coping with threatening illness situations. Middle-range theoretical frameworks provide some evidence to support the relationships posed. However, to date no nursing theories have sufficient evidence to be considered “laws,” which is not unexpected, given that nursing is a newly established discipline and our phenomena of interest are highly complex