4. Single or multi‐component interventions: data not included in main analyses.

Outcome	Effect estimate and 95% CI	Number of studies and study ID	Participants (n)
Single component interventions
Adherence: APCD scale	MD 22.00 (95% CI 8.40 to 36.00)	1 study (Naderloo 2018)	54
HA: length of stay (mean days)	MD 3.80 (95% CI –1.77 to 9.37)	1 study (Hagedorn 2013)	212
Multi‐component interventions
Adherence: mean MRA score	MD 8.20 (95% CI 4.34 to 12.06)	1 study (Tommelein 2014)	692
Adherence: mean TAI score (change from baseline to hospital discharge)	MD 1.02 (95% CI –1.21 to 3.25)	1 study (Grandos‐Santiago 2020)	42
HA: non‐COPD hospitalisations HA: COPD‐related hospitalisations	MD –0.05 (95% CI –0.25 to 0.15) MD –0.25 (95% CI –0.55 to 0.05	1 study (Thom 2018)	192
HA: number of people admitted to ED	MD 0.87 (95% CI 0.48 to 1.57)	2 studies (Jarab 2012; Tommelein 2014)	825
HA: non‐COPD ED visits HA: COPD‐related ED visits	MD 0.15 (95% CI –0.45 to 0.75) MD –0.09 (95% CI –0.61 to 0.43)	1 study (Thom 2018)	192
HA: rate of ED visits per patient per year	RR 0.59 (95% CI 0.27 to 1.29)	1 study (Tommelein 2014	692
HA: length of stay per participant	MD –5.54 (95% CI –11.61 to 0.53)	1 study (Wei 2014)	87
HA: rate of hospital days per year	RR, IV 0.27 (95% CI 0.21 to 0.35)	1 study (Tommelein 2014)	692
Exacerbations: mean exacerbations per year	MD –0.27 (95% CI –6.01 to 5.47)	1 study (Thom 2018)	192
Exacerbations: rate of severe exacerbations per participant per year	RR 0.45 (95% CI 0.25 to 0.81)	1 study (Tommelein 2014)	692

APCD: Adherence among Patients with Chronic Disease; CAT: COPD Assessment Test; CI: confidence interval; COPD: chronic obstructive pulmonary disease; ED: emergency department; HA: hospital admissions; IV: inverse variance; MD: mean difference; MRA: Medication Refill Adherence scale; n: number of participants; OR: odds ratio; QoL: quality of life; RR: rate ratio; TAI: Test of Adherence to Inhalers.