The average menstrual cycle is 28 days long. However, a normal cycle can be shorter or longer than this. It may be anywhere from 21 to 35 days long. Most periods last 3 to 5 days, but anywhere from 2 to 7 days is normal.Menstrual cycles may happen around the same date every month or they may be irregular.A menstrual period is considered late if it hasnât started 5 or more days after the day you expected it to start.A period is considered missed if you have had no menstrual flow for 6 or more weeks after the start of your last period.enstrual cycles may happen around the same date every month or they may be irregular. A menstrual period is considered late if it hasnât started 5 or more days after the day you expected it to start. A period is considered missed if you have had no menstrual flow for 6 or more weeks after the start of your last period.
Transcript of Theory of Dorothy Johnson. Theory of Dorothy Johnson. The Behavioral System Model. Johnsonâs Behavioral System Model is a model of nursing care that advocates the fostering of efficient and effective behavioral functioning in the patient to prevent illness.
Royâs model was conceived when nursing theorist Dorothy Johnson challenged her students during a seminar to develop conceptual models of nursing. Johnsonâs nursing model was the impetus for the development of Royâs Adaptation Model.Royâs model incorporated concepts from Adaptation-level Theory of Perception from renown American physiological psychologist Harry Helson, Ludwig von Bertalanffyâs System Model, and Anatol Rapoportâs system definition.he Roy Adaptation Model was first presented in the literature in an article published in Nursing Outlook in 1970 entitled âAdaptation: A Conceptual Framework for Nursing.â In the same year, Royâs Adaptation Model of Nursing was adapted in Mount St. Maryâs School in Los Angeles, California.