Received: 28 November 2019
Accepted: 18 May 2020
First Online: 11 June 2020
Ethics approval and consent to participate
: Ethical clearance and approval were obtained from the institutional review board of Addis Ababa University, college of health science, and School of Public Health. Before performing measurements, verbal and written consent was obtained from each study participants, and participant informed that they have full rights to refuse and discontinue participating at any point in the study. The study participants with lung function impairments were advised and linked to a health facility.
: The authors declare that they have no competing interests.