Characteristics of included studies
| Authors (year) [ref.] | Sample | Healthcare setting | Data collection | Type of methodology | Quality appraisal score using Atkin's quality appraisal tool |
| Bauer and Schiffman (2020) [38] | 28 patients (12 men, 16 women), Mean of 4 comorbidities, 6 current smokers, 18 ex-smokers, 4 nonsmokers | Primary care | Semi-structured interviews | Thematic analysis | 12 |
| Ellison et al. (2012) [39] | 14 patients (7 men, 7 women), 7 current smokers and 7 ex-smokers | Primary care | In-depth semi-structured interviews (40 to 60 min) | Thematic analysis | 13 |
| Fotokian et al. (2017) [54] | 15 patients with COPD | General healthcare setting | In-depth semi-structured interviews (30–100 min) | Grounded theory | 13 |
| Gorst et al. (2016) [58] | 8 patients (5 women, 3 men) | Telehealthcare | Face-to-face semi-structured interviews (mean=45 min) | Interpretative Phenomenological Analysis (IPA) | 13 |
| Guo and Bruce (2014) [45] | 25 participants (12 women, 13 men), 8 current smokers, 16 nonsmokers, 1 experimenter | Pulmonary rehabilitation | Focus group discussions using a semi-structured topic guide | Thematic analysis | 12 |
| Halding et al. (2018) [40] | 11 patients (6 men, 5 women), 4 answered YES to smoking | Primary care | Semi-structured interviews (45–90 min) | Content analysis | 13 |
| Halding et al. (2010) [46] | 18 participants (13 men, 5 women), 11 were ex-smokers and 5 were current smokers | Pulmonary rehabilitation | 33 qualitative interviews (40–90 min), 2 sessions with each participant | Interpretive phenomenology | 12 |
| Halding et al. (2011) [23] | 18 participants (13 men, 5 women), 11 were ex-smokers and 5 were current smokers | Pulmonary rehabilitation | 33 qualitative interviews (40–90 min), 2 sessions with each participant | Qualitative content analysis | 12 |
| Harb et al. (2017) [41] | 26 patients (11 men, 15 women), 10 had arthritis, 7 asthma, 5 hypertension, 5 obstructive sleep apnoea, 5 diabetes, 4 osteoporosis, 3 cardiovascular disease, 2 hypercholesterolaemia and 17 other | Primary care setting and specialist care | Semi-structured in-depth interviews (∼45 min) | Thematic analysis using treatment-burden framework | 12 |
| Hellem et al. (2012) [47] | 11 participants (3 men, 8 women), all had smoking history except 1 | Pulmonary rehabilitation | In-depth interviews and focus group discussion | Content analysis, phenomenological approach | 12 |
| Kayyali et al. (2018) [42] | 18 patients (11 women, 7 men) | Primary care setting | Semi-structured interviews | Thematic analysis using inductive/deductive approaches | 12 |
| Keating et al. (2011) [48] | 37 patients (18 men, 19 women), 10 current smokers, all had at least 1 comorbidity (1–7) | Pulmonary rehabilitation | Semi-structured interviews | Thematic analysis | 13 |
| Lindgren et al. (2014) [15] | 8 participants (3 male, 5 female), 7 ex-smokers and 1 smoker | General healthcare setting | 60 to 110 min interviews | Phenomenological–hermeneutical approach | 12 |
| Luckett et al. (2017) [49] | 20 participants (9 women), 15 had COPD | Pulmonary rehabilitation | Semi-structured interviews (22–70 min) | Phenomenology | 13 |
| Moore et al. (2012) [50] | 24 participants (14 men, 10 women) | Pulmonary rehabilitation | Semi-structured interviews (mean 1 h) | Thematic analysis | 13 |
| Oliver (2001) [44] | 16 patients (12 men) | General practice | Semi-structured interviews (45–85 min) | Thematic analysis | 13 |
| Robinson (2005) [56] | 10 patients | General healthcare setting | Unstructured interviews | Qualitative phenomenological approach | 10 |
| Shipman et al. (2009) [43] | 16 patients (9 men), 10 patients had comorbidities including heart disease, rheumatoid arthritis, diverticulitis, osteoporosis and diabetes mellitus | GP and hospital | In-depth qualitative interviews | Framework approach | 12 |
| Sully et al. (2012) [51] | 23 patients | Pulmonary rehabilitation | Focus group discussions (45 to 60 min) | Grounded theory complemented with content matrix | 13 |
| Wodskou et al. (2014) [57] | 34 patients (15 men, 19 women) | General healthcare setting | Focus groups and semi-structured interviews | Inductive content analysis | 12 |
| Hopley et al. (2009) [52] | 9 patients (almost equal number of men and women), 7 ex-smokers, 1 current smoker | Specialist care | In-depth semi-structured interviews | General inductive approach with emerging themes | 12 |
| Andersen et al. (2018) [53] | 10 patients (7 women, 3 men) | General healthcare setting | Repeated in-depth ethnographic interviews and patient observations | Phenomenological–hermeneutical approach | 12 |
| Korpershoek et al. (2016) [55] | 15 patients (8 male, 7 female) | General healthcare setting | Semi-structured in-depth individual interviews | Grounded theory | 13 |