The Effect of 20-Minute Mindful Breathing on the Rapid Reduction of Dyspnea at Rest in Patients With Lung Diseases: A Randomized Controlled Trial by Tan, Seng Beng, Liam, Chong Kin, Pang, Yong Kek, Ng, Diana Leh Ching, Wong, Tat Seng, Khoo, Kelvin Wei Shen, Ooi, Chieh Yin, Chai, Chee Shee