Results observed in the primary randomised controlled crossover trial of fan therapy versus no fan therapy during 6-min walk test (6MWT) in patients with COPD
| Allocation sequence AB (fan/no fan) | Allocation sequence BA (no fan/fan) | Overall treatment effect | ||||||||
| Group-level median (IQR) | WIDiM (IQR) | Group-level median (IQR) | WIDiM (IQR) | WIDiM (IQR) | ||||||
| Period 1 fan | Period 2 no fan | WIDiM# | Wilcoxon signed rank test¶ | Period 1 no fan | Period 2 fan | WIDiM# | Wilcoxon signed rank test¶ | WIDiM# | Wilcoxon signed rank test¶ | |
| Patients (n) | 7 | 7 | 7 | 6 | 6 | 6 | 13 | |||
| Subjective measures of breathlessness | ||||||||||
| NRS+ | 5.00 (3.75 to 6.25) | 7.00 (6.25 to 8.25) | −2.00 (−2.00 to −1.00) | 0.02 | 4.00 (2.50 to 5.75) | 3.00 (2.00 to 4.75) | −0.50 (−1.25 to 0.00) | 0.25 | −1.00 (−2.00 to −0.50) | <0.01 |
| ΔNRS§ | 3.00 (1.25 to 4.25) | 5.00 (3.00 to 6.75) | −1.50 (−2.00 to −1.00) | 0.02 | 3.50 (2.25 to 4.75) | 3.00 (1.75 to 3.25) | −0.50 (−1.25 to 0.00) | 0.25 | −1.00 (−2.00 to −0.50) | <0.01 |
| NRS recovery time+ | 110.00 (15.00 to 135.00) | 210.00 (160.00 to 295.00) | −90.00 (−205.00 to −32.50) | 0.03 | 150.00 (75.00 to 195.00) | 210.00 (165.00 to 227.50) | 60.00 (10.00 to 65.00) | 0.09 | −10.00 (−78.75 to 50.00) | <0.01 |
| mBorg+ | 3.00 (0.75 to 3.50) | 4.00 (4.00 to 5.00) | −1.00 (−2.50 to 0.25) | 0.06 | 3.00 (2.00 to 4.50) | 3.00 (1.00 to 3.50) | 0.00 (−1.00 to 0.00) | 0.50 | −0.25 (−2.00 to 0.00) | 0.02 |
| ΔmBorg§ | 2.00 (0.25 to 3.00) | 3.50 (3.50 to 4.00) | −1.00 (−2.50 to −0.25) | 0.06 | 3.00 (1.75 to 3.50) | 2.00 (0.75 to 3.00) | 0.00 (−1.00 to 0.00) | 0.50 | −0.25 (−2.00. 0.00) | 0.02 |
| Objective measures of physiology | ||||||||||
| HR+ | 84.00 (74.00 to 89.50) | 82.00 (79.00 to 96.00) | −4.00 (−12.00 to 4.00) | 0.38 | 96.00 (94.00 to 106.50) | 92.00 (85.50 to 97.50) | −3.00 (−5.50 to −2.00) | 0.14 | −3.50 (−7.50 to 1.00) | 0.11 |
| ΔHR§ | 11.00 (5.50 to 14.00) | 12.00 (8.50 to 19.00) | −3.00 (−5.50 to −1.00) | 0.20 | 15.00 (4.00 to 18.00) | 2.00 (0.50 to 14.00) | −3.00 (−5.50 to −1.00) | 0.47 | −3.00 (−5.75 to −0.25) | 0.13 |
| SpO2+ | 96.00 (94.50 to 98.50) | 97.00 (96.50 to 98.00) | 0.00 (−1.00 to 1.00) | 1.00 | 96.00 (95.00 to 96.50) | 97.00 (95.00 to 97.00) | 0.00 (−1.00 to 1.00) | 0.94 | 0.00 (−1.00 to 1.00) | 0.70 |
| Δ SpO2§ | 0.00 (−1.00 to 1.50) | 0.00 (−1.00 to 1.00) | 0.00 (−0.50 to 1.00) | 1.00 | 0.00 (−1.50 to 0.50) | 0.00 (−1.50 to 1.00) | 0.00 (-1.00 to 1.00) | 1.00 | 0.00 (−0.75 to 1.00) | 1.00 |
| Objective measures of functional response | ||||||||||
| 6MWT distanceƒ (m) | 404.00 (336.25 to 465.00) | 400.00 (312.50 to 420.00) | 25.00 (17.50 to 30.00) | 0.02 | 330.00 (223.75 to 517.50) | 383.00 (247.50 to 561.25) | 15.00 (11.00 to 42.75) | 0.02 | 21.25 (12.75 to 31.88) | <0.01 |
| 6MWT stopsƒ (n) | 0.00 (0.00 to 0.00) | 0.00 (0.00 to 1.00) | 0.00 (−0.50 to 0.00) | 1.00 | 0.00 (0.00 to 2.00) | 0.00 (0.00 to 1.50) | 0.00 (0.00 to 0.00) | 1.000 | 0.00 (0.00 to 0.00) | 0.63 |
Only within-individual differences in the medians (WIDiMs) are used for estimating treatment effects; group-level medians are helpful in assessing carryover and order effects (see methods section). IQR: interquartile range; NRS: numerical rating scale; Δ: change; mBorg: modified Borg scale for breathlessness; HR: heart rate; SpO2: oxygen saturation measured by pulse oximetry. #: calculated so that positive values indicate higher scores for the fan condition and negative values indicate higher scores for the no-fan condition; ¶: exact significant, two-tailed; +: assessed post-exercise; §: change from pre- to post-exercise; ƒ: assessed during the exercise period.