Instruments
chest pain, pain
CHRONIC DISEASE
Data collection instruments were a demographic questionnaire, a clinical data sheet, and a visual analogue scale. The items of the demographic questionnaire were related to age, gender, educational level, body mass index, occupation, pain tolerance, history of chronic disease, history of cigarette smoking, and family history of coronary artery bypass graft surgery. The clinical data sheet included items on chest tube characteristics, namely chest tube size, duration of chest tube use, and chest pain. The visual analogue scale for pain assessment was scored from zero (“No pain”) to 10 (“Highest possible pain”). This scale has been used in previous studies for pain assessment among patients with cardiac surgery [