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. 2019 Aug 1;14:1713–1719. doi: 10.2147/COPD.S202640

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© 2019 Alrajeh et al.

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The geographical location of the respondents expressed in percentage. Other includes Serbia, Australia, Switzerland, Austria, Italy, Germany, Netherlands, Norway, Denmark, Slovenia, Malta, Ghana, Guyana, Namibia, Pakistan, Philippines, Niger, Singapore, South Africa, Sir Lanka, and Mongolia.