*3.2. Study Characteristics*

In total, 19 studies [19,22–30,33,35,38,41,43–47] were published in China, two were published in Italy [18,42], Poland [31,34], and the United Kingdom [20,39], and one was published in the USA [36], Brazil [37], Australia [21], Turkey [32], and Taiwan [40]. There were 11 studies [18,20,21,31,32,34,36–38,42,47] using Western manual therapy, of which four [18,34,36,42] were related to manipulation, four [21,31,32,47] were regarding massage, and one study each was related to release technique [37], manual chest technique [20], and manual percussion [38]. Nineteen studies [19,22–30,33,35,39–41,43–46] used Eastern manual therapy, of which 10 [22–24,28,30,33,40,41,45,46] were related to acupressure, five [25–27,29,39] pertained to foot reflexology, and four [19,35,43,44] were regarding tuina. As for the COPD stage, 16 studies [18,19,25–30,34–37,39,42,43,45] targeted stable COPD participants, eight studies [20,22–24,31,33,38,46] were on AECOPD, and six studies [21,32,40,41,44,47] did not specify the stage. Nine studies [22–24,28–30,35,41,45] targeted

participants with specific pattern identification, of which four focused on participants with phlegm-heat [22], phlegm turbidity [23,41], or phlegm-blood stasis [24] obstructing the lung, and five [28–30,35,45] targeted dual deficiency of lung–spleen or lung–kidney. Twelve studies [18,20–24,32,34,36,37,42,45] were approved by the Institutional Review Board prior to study commencement, and 19 studies [18,20–26,29,32,34–37,40–42,45,47] received consent forms from the participants (Tables 1 and 2).
