Effects of a COPD self-management support intervention: a randomized controlled trial

Figures & data

Figure 1 Overview of recruitment, allocation, and randomization.

Abbreviations: ITT, intention to treat; PPA, per-protocol analysis.

Table 1 Characteristics of participants at baseline

	Randomized (N=182)j	Intervention (N=92)j	Control (N=90)j
	Value	Value	Value
Age (years)	68.93±8.58	68.53±8.16	69.34±9.02
Sex, male	111 (61.0)	54 (58.7)	57 (63.3)
Education
Primary school	57 (32.2)	29 (31.9)	28 (32.6)
High school/university	120 (67.8)	62 (68.1)	58 (67.4)
Cohabitation, living alonea	54 (30.0)	27 (29.3)	27 (30.7)
Other chronic diseaseb	170 (96.6)	87 (95.6)	83 (97.6)
Comorbidityc	2.51±1.87	2.68±1.91	2.33±1.82
FEV1% predicted	45.03±15.31	45.22±14.44	44.84±16.23
GOLDd grade
GOLD II	73 (40.1)	35 (38.0)	38 (42.2)
GOLD III	73 (40.1)	42 (45.7)	31 (34.4)
GOLD IV	36 (19.8)	15 (16.3)	21 (23.3)
Years diagnosed with COPD	8.83±5.87	9.20±6.25	8.47±5.49
CATe score	19.09±7.35	18.68±7.15	19.51±7.58
mMRCf score	1.82±1.09	1.88±1.06	1.76±1.12
mMRC grade 0	20 (11.6)	7 (7.9)	13 (15.5)
mMRC grade 1	51 (29.5)	29 (32.6)	22 (26.2)
mMRC grade 2	51 (29.5)	27 (30.3)	24 (28.6)
mMRC grade 3	42 (24.3)	20 (22.5)	22 (26.2)
mMRC grade 4	9 (5.2)	6 (6.7)	3 (3.6)
Self-management domainsg
Positive and active engagement in life	2.92±0.44	2.96±0.41	2.88±0.46
Health directed activities	2.63±0.63	2.63±0.68	2.64±0.58
Skill and technique acquisition	2.70±0.44	2.73±0.45	2.68±0.43
Constructive attitudes and approaches	2.89±0.44	2.90±0.40	2.88±0.48
Self-monitoring and insight	3.03±0.35	3.06±0.35	3.00±0.35
Health service navigation	2.87±0.38	2.93±0.38	2.82±0.38
Social integration and support	2.80±0.44	2.83±0.41	2.77±0.48
Emotional distress	2.38±0.62	2.41±0.62	2.34±0.63
GSE,h total score	25.97±6.42	26.92±6.16	24.96±6.57
SOC-13,i total score	64.59±9.64	65.10±9.64	64.06±9.66

Notes: Data are shown as mean ± SD or n (%).

a Cohabitation: living alone; living with someone.

b Other chronic disease: yes; no.

c Comorbidity: rated between 0 (no comorbidities) and 16 based on a list of common comorbidities.

d GOLD, grading of lung function; mild (I), moderate (II), severe (III), or very severe (IV), defined as FEV₁/FVC <0.7 and FEV₁% ≥80% (I), FEV₁% 50%–79% (II), FEV₁% 30%–49% (III), or FEV₁% <30% (IV).

e CAT: score range: 0–40.

f mMRC: score range: 0–4.

g Domains of the heiQ: score range: 1–4.

h GSE: score range: 10–40.

i SOC-13: score range: 13–91.

j N=182, N=92, and N=90 are the largest N values; for some variables the N is lower.

Abbreviations: CAT, COPD Assessment Test; GOLD, Global Initiative for Chronic Obstructive Pulmonary Disease; GSE, General Self-Efficacy Scale; heiQ, Health Education Impact Questionnaire; mMRC, modified Medical Research Council Dyspnoea Scale; SOC-13, 13-item Sense of Coherence Scale.

Table 2 Effects of better living with COPD (primary outcomes) evaluated by PPA and ITT analysis, ANCOVA: means from baseline and follow-up, mean change difference and effect size

Self- management domains		PPAc								ITT
		Control		Intervention		Mean change differenceb				Control		Intervention		Mean change differenceb
		N	Mean ± SDa	N	Mean ± SDa	Mean	95% CI	d	P-valued	N	Mean ± SDa	N	Mean ± SDa	Mean	95% CI	d	P-valued
Positive and active engagement in life	Baseline	68	2.87±0.47	54	2.94±0.40					86	2.88±0.46	91	2.96±0.41
	Follow-up	68	2.91±0.49	54	3.00±0.32	0.02	−0.13 to 0.17	0.04	0.3634	68	2.91±0.47	60	2.97±0.33	0.00	−0.14 to 0.14	0.00	0.5543
Health directed activities	Baseline	67	2.60±0.54	54	2.53±0.71					85	2.64±0.58	91	2.63±0.68
	Follow-up	69	2.67±0.53	54	2.68±0.59	0.13	−0.04 to 0.30	0.27	0.3154	69	2.67±0.53	60	2.70±0.59	0.11	−0.05 to 0.28	0.25	0.3225
Skill and technique acquisition	Baseline	68	2.68±0.45	54	2.78±0.44					86	2.68±0.43	90	2.73±0.45
	Follow-up	67	2.70±0.35	55	2.85±0.40	0.06	−0.07 to 0.19	0.17	0.0405	67	2.70±0.35	61	2.85±0.38	0.06	−0.06 to 0.19	0.17	0.0356
Constructive attitudes and approaches	Baseline	68	2.88±0.46	54	2.93±0.43					86	2.88±0.48	90	2.90±0.40
	Follow-up	67	2.87±0.41	54	3.09±0.39	0.16	0.03 to 0.30	0.38	0.0021	67	2.87±0.41	61	3.07±0.41	0.14	0.00 to 0.27	0.32	0.0069
Self-monitoring and insight	Baseline	69	2.97±0.34	54	3.05±0.33					87	3.00±0.35	91	3.06±0.35
	Follow-up	69	2.98±0.32	55	3.11±0.27	0.05	−0.07 to 0.18	0.15	0.0494	69	2.98±0.32	61	3.09±0.27	0.02	−0.10 to 0.15	0.07	0.0944
Health service navigation	Baseline	68	2.79±0.37	54	2.92±0.35					86	2.82±0.38	91	2.93±0.38
	Follow-up	67	2.86±0.39	55	3.00±0.37	−0.00	−0.14 to 0.13	−0.01	0.3606	67	2.86±0.39	62	3.00±0.38	0.00	−0.13 to 0.13	0.00	0.3635
Social integration and support	Baseline	69	2.79±0.48	53	2.80±0.42					87	2.77±0.48	89	2.83±0.41
	Follow-up	67	2.78±0.46	55	2.82±0.46	0.02	−0.11 to 0.16	0.06	0.5623	67	2.78±0.46	61	2.82±0.45	0.02	−0.11 to 0.14	0.05	0.5840
Emotional distress	Baseline	68	2.32±0.60	54	2.30±0.61					86	2.34±0.63	90	2.41±0.62
	Follow-up	67	2.29±0.56	55	2.31±0.70	−0.04	−0.22 to 0.14	−0.08	0.8809	67	2.29±0.56	61	2.32±0.71	−0.03	−0.20 to 0.14	−0.06	0.8914

Notes:

a Means are presented from the data, therefore all participants (the total intervention and control groups) who provided data are included in the ITT description of means, including those with responses at only baseline or follow-up.

b Mean change difference in both PPA and ITT is from the data; therefore, for both PPA and ITT only those with responses at both baseline and follow-up are represented.

c Included in PPA were those who participated in more than half of the sessions on Better living with COPD.

d P-value is from the ANCOVA based on multiple imputation (50 imputed data sets based on information on heiQ, education, FEV₁%, GSE, and SOC). A P-value <0.05 was considered statistically significant and is marked in bold.

Abbreviations: ANCOVA, analysis of covariance; d, Cohen’s d; GSE, general self-efficacy; heiQ, Health Education Impact Questionnaire; ITT, intention-to-treat; PPA, per-protocol analysis; SOC, sense of coherence.