The women with breast cancer in the intervention group received two sessions of laughter therapy per week for eight weeks.Each laughter therapy session lasted 40 minutes.

The control group did not receive any intervention during the study period.

Each session started with a 10-minute breathing exercise accompanied by relaxing music, followed by 20-minute laughing exercises. Afterwards, the session was ended with a 10-minute meditation accompanied by relaxing music.

The scale consists of 14 items in total and was designed to measure how stressful the changing situations in the individual's life are perceived.The scale is a 5-point Likert-type scale with each item ranging from "never (0)" to "very often (4)". 7 of the scale items with positive expressions are scored in reverse and the total score that can be obtained from the scale ranges from 0 to 56. Eskin et al. performed the validity and reliability study of the Turkish version of Perceived Stress Scale and the internal consistency of the scale was determined to be 0.82.

The scale evaluates the quality of life of individuals.The scale consists of 12 items and two sub-dimensions in total.While the items related to physical and emotional role were answered as yes or no, the other items had likert type options ranging between 3 and 6. While the Physical Component Summary-12 (PCS-12) score was obtained from the sub-dimensions of general health, physical functionality, physical role and body pain; The Mental Component Summary-12 (MCS-12) score was obtained from the sub-dimensions of social functionality, emotional role, mental health and energy. Both the PCS-12 and MCS-12 scores range from 0 to 100, with the higher score representing better health.Soylu et al. performed the validity and reliability study of the Turkish version of Quality of Life Scale (SF-12) and the internal consistency of the scale was determined to be 0.73.