Subgroup analyses: differences between the COPD-GRIP (Chronic Obstructive Pulmonary Disease – Guidance, Research on Illness Perception) intervention group and the usual-care group in Clinical COPD Questionnaire scores
| Subjects n | Baseline | 6 weeks | 3 months | 9 months | Treatment*time interaction p-values | |
| MRC score ≤2 | 0.595 | |||||
| Intervention | 64 | 1.3±0.7 | 1.3±0.7 | 1.3±0.9 | 1.5±0.8 | |
| Usual care | 68 | 1.2±0.8 | 1.2±0.8 | 1.3±0.8 | 1.3±0.7 | |
| MRC score >2 | 0.165 | |||||
| Intervention | 20 | 3.0±1.1 | 3.0±1.1 | 3.2±1.1 | 3.2±1.1 | |
| Usual care | 23 | 2.7±0.9 | 2.9±1.0 | 3.0±0.9 | 3.0±1.0 | |
| Male | 0.811 | |||||
| Intervention | 33 | 1.8±1.3 | 1.4±0.9 | 1.8±1.3 | 1.7±1.0 | |
| Usual care | 41 | 1.7±1.0 | 1.9±1.1 | 1.8±1.1 | 1.8±1.3 | |
| Female | 0.126 | |||||
| Intervention | 51 | 2.2±1.3 | 2.1±1.2 | 2.3±1.4 | 2.2±1.3 | |
| Usual care | 53 | 1.6±1.1 | 1.6±1.2 | 1.8±1.1 | 1.6±1.0 |
Data are presented as mean±sd, unless otherwise stated. MRC: Medical Research Council.