Table 5.

Subgroup analyses by injury characteristics for intent to treat analysis of primary outcome of excellent recovery (total FAOS ≥450) in patients with acute ankle sprain randomised to usual care with physiotherapy or usual care alone

Follow-up	No (%) of patients		Raw risk difference* (95% CI)	Adjusted risk difference* (95% CI)†	P value‡
	Physiotherapy	Usual care
Non-sports injury
Baseline	0/143 (0)	0/145 (0)	—	—	—
1 month	13/135 (10)	18/137 (13)	−4% (−11% to 4%)	−2% (−9% to 4%)	0.32
3 months	56/131 (43)	48/124 (39)	4% (−8% to 16%)	3% (−8% to 14%)	0.66
6 months	63/117 (54)	70/112 (63)	−9% (−21% to 4%)	−9% (−21% to 3%)	0.13
Sports injury
Baseline	0/110 (0)	0/105 (0)	—	—	—
1 month	13/104 (13)	16/102 (16)	−3% (−13% to 6%)	−0% (−8% to 7%)	0.61
3 months	42/98 (43)	31/90 (34)	8% (−5% to 22%)	9% (−3% to 22%)	0.22
6 months	55/91 (60)	50/83 (60)	0% (−14% to 15%)	0% (−14% to 14%)	0.93
Grade 1
Baseline	0/69 (0)	0/80 (0)	—	—	—
1 month	10/66 (15)	15/75 (20)	−5% (−17% to 8%)	2% (−13% to 16%)	0.37
3 months	38/67 (57)	35/68 (51)	5% (−12% to 22%)	4% (−12% to 21%)	0.60
6 months	43/60 (72)	46/64 (72)	−0% (−16% to 16%)	−2% (−18% to 13%)	0.89
Grade 2
Baseline	0/184 (0)	0/170 (0)	—	—	—
1 month	16/173 (9)	19/164 (12)	−2% (−9% to 4%)	−2% (−7% to 3%)	0.42
3 months	60/162 (37)	44/146 (30)	7% (−4% to 17%)	6% (−3% to 16%)	0.26
6 months	75/148 (51)	74/131 (56)	−6% (−18% to 6%)	−6% (−18% to 5%)	0.26

*Positive risk difference favours physiotherapy arm.

†Adjusted risk difference uses generalised linear model with binomial outcome and identity link to control for quarter of FAOS at baseline.

‡P value based on Mantel-Haenszel test, stratified by quarter of FAOS at baseline.

§P value for subgroup by treatment interaction 0.77 at 1 month, 0.50 at 3 months, and 0.27 at 6 months.

¶P value for subgroup by treatment interaction 0.97 at 1 month, 0.85 at 3 months, and 0.59 at 6 months.