Results observed in the repeated 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 | 7 | 7 | 7 | 13 | |||
| Subjective measures of breathlessness | ||||||||||
| NRS+ | 5.00 (3.50 to 5.50) | 5.50 (4.25 to 7.00) | −1.00 (−1.00 to −0.75) | 0.03 | 3.80 (0.75 to 6.00) | 1.80 (0.38 to 5.00) | −0.25 (−0.88 to 0.00) | 0.25 | −1.00 (−1.00 to 0.00) | <0.01 |
| ΔNRS§ | 3.50 (2.25 to 3.75) | 4.00 (2.75 to 4.75) | −1.00 (−1.00 to −0.75) | 0.03 | 1.80 (0.75 to 2.75) | 1.80 (0.38 to 2.00) | −0.25 (−0.88 to 0.00) | 0.25 | −1.00 (−1.00 to 0.00) | <0.01 |
| NRS recovery time+ | 120.00 (75.00 to 180.00) | 185.00 (152.50 to 277.50) | −110.00 (−127.00 to −62.50) | 0.02 | 175.00 (43.75 to 227.50) | 105.00 (25.75 to 185.00) | −17.00 (−102.50 to −11.00) | 0.06 | −65.00 (−130.00 to −20.00) | <0.01 |
| mBorg+ | 3.00 (2.00 to 4.00) | 4.00 (3.00 to 4.50) | −1.00 (−2.00 to −0.50) | 0.06 | 2.50 (0.88 to 5.25) | 1.50 (0.25 to 5.00) | −0.25 (−0.88 to 0.00) | 0.250 | −1.00 (−2.00 to 0.00) | <0.01 |
| ΔmBorg§ | 3.00 (1.00 to 3.00) | 3.00 (2.50 to 3.50) | −1.00 (−2.00 to −0.50) | 0.06 | 2.50 (0.88 to 3.00) | 1.50 (0.25 to 2.00) | −0.25 (−0.88 to 0.00) | 0.25 | −1.00 (−2.00 to 0.00) | <0.08 |
| Objective measures of physiology | ||||||||||
| HR+ | 89.00 (84.50 to 99.50) | 87.00 (85.00 to 99.50) | 0.00 (−4.50 to 1.50) | 0.69 | 89.50 (86.75 to 91.50) | 84.50 (81.75 to 90.25) | −1.50 (−6.50 to 2.75) | 0.69 | 0.00 (−6.00 to 2.00) | 0.49 |
| ΔHR§ | 10.00 (5.00 to 15.00) | 10.00 (10.00 to 12.00) | 0.00 (−6.00 to 4.00) | 0.88 | 6.00 (2.50 to 12.50) | 5.50 (2.75 to 12.75) | 1.00 (−2.00 to 2.50) | 0.85 | 1.00 (−3.00 to 3.00) | 0.96 |
| SpO2+ | 94.00 (92.50 to 95.50) | 94.00 (93.00 to 97.00) | 0.00 (−3.00 to 0.00) | 0.25 | 98.0 (96.50 to 98.00) | 96.50 (96.00 to 97.75) | 0.00 (−0.75 to 0.00) | 0.75 | 0.00 (−2.00 to 0.00) | 0.16 |
| Δ SpO2§ | 0.00 (−3.50 to 1.00) | −1.00 (−1.50–0.50) | −1.00 (−2.50 to 1.50) | 0.52 | 0.50 (−1.50 to 2.50) | −0.50 (−1.00 to 0.00) | −1.00 (−1.75 to 0.50) | 0.53 | −1.00 (−2.00 to 1.00) | 0.29 |
| Objective measures of functional response | ||||||||||
| 6MWT distanceƒ (m) | 282.50 (233.75 to 470.25) | 265.00 (209.75 to 430.00) | 28.00 (20.00 to 38.75) | 0.06 | 432.50 (399.38 to 516.25) | 531.30 (421.25 to 560.63) | 22.50 (11.25 to 71.25) | 0.06 | 28.00 (17.50 to 45.00) | <0.01 |
| 6MWT stopsƒ (n) | 0.00 (0.00 to 2.00) | 1.00 (0.00 to 1.50) | 0.00 (0.00 to 0.00) | 1.00 | 0.00 (0.00 to 0.00) | 0.00 (0.00 to 0.00) | 0.00 (0.00 to 0.00) | 1.00 | 0.00 (0.00 to 0.00) | 0.75 |
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.