Table 3 Construct validity
From: Fatigability in spinal muscular atrophy: validity and reliability of endurance shuttle tests
ESNHPT | ESBBT | ESWT | |
|---|---|---|---|
Discriminative validity | SMA – HC - DC | SMA - HC | SMA - HC |
Time to limitation (Mdn (s)) | SMA (N = 55): 937 (48–1200) HC P1 (N = 15): 600 HC P2 (N = 9): 1200 DC (N = 15): 1200 (967–1200) | SMA (N = 37): 245 (50–1200) HC P1 (N = 15): 600 HC P2 (N = 5): 1200 | SMA (N = 15): 861 (218–1200) HC P1 (N = 12): 600 HC P2 (N = 8): 1200 |
Drop-out (%) | SMA: 54.5% HC: 0% DC: 6.7% SMA type 2: 73.3% SMA type 3a: 63.6% SMA type 3b: 7.1% | SMA: 70.3% HC: 5% SMA type 2: 100% SMA type 3a: 80% SMA type 3b-4: 44% | SMA: 73.3% HC: 0% |
Convergent validity | SMA | SMA | SMA |
Muscle strength (N) | No decrease | SA: −5.5 (2.1), p = .013 | KF: - 8.9, p = .011 |
Perceived fatigue (0–10) | G: + 1.1 (0.2), p = .000 UA: + 2.6 (0.3), p = .000 LA: + 2.8 (0.4), p = .000 H: + 2.4 (0.4), p = .000 | UA: + 2.6 (0.4), p = .000) LA: + 2.1 (0.4), p = .000 H: + 1.0 (0.3), p = .000 | G: + 3.7 (0.77), p = .000 UL: + 4.0 (.92), p = .001 |
Motor adaptation (Yes) | No drop-out: 26% Drop-out: 96% | No drop-out: 33% Drop-out: 96% | No drop-out: 75% Drop-out: 100% |