Table 4.

Regression analyses and Spearman’s correlation of clinical outcome versus HADS score Linear regression and correlation analyses between improvement in KOOS subscales and NRS versus HADS subscale scores

		Improvement Baseline vs. 6 months, median (range)		β – Slope (95% CI)	p value	R2	Spearman’s ρ (95% CI)
		HADS < 8	HADS ≤ 8
HADS-A	KOOS: Pain	19.5 (9.7–50)	9.8 (5.5–16.8)	- 0.8 [(−1.5) – (−0.1)]	< 0.05	0.05	0.17 (0.05–0.37)
	KOOS: Symptoms and Stiffness	20.8 (5.5–60.8)	3.8 (3.5–50)	- 2.2 [(−3.3) – (−1.0)]	< 0.001	0.21	0.43 (0.18–0.63)
	KOOS: Daily living	30.0 (8.8–61.8)	11.9 (1.5–48.5)	- 2.1 [(−3.3) – (−1.1)]	< 0.001	0.23	0.44 (0.19–0.64)
	KOOS: Sports and recreation	15.0 (5.0–95)	11.3 (0.0–25)	- 1.6 [(−3.0) – (−0.3)]	< 0.05	0.12	0.41 (0.13–0.64)
	KOOS: Quality of life	12.5 (5.5–93.8)	6.3 (0.0–31.3)	- 1.8 [(−3.2) – (−0.4)]	< 0.05	0.12	0.36 (0.09–0.57)
	Numeric rating scale	3.0 (1.0–6.0)	1.0 (0.0–5.0)	- 0.1 [(−0.3) – (−0.2)]	< 0.05	0.07	0.30 (0.09–0.48)
HADS-D	KOOS: Pain	33.3 (11.0–69.5)	22.1 (0.0–36.0)	- 1.1 [(−2.2) – (−0.1)]	< 0.05	0.10	0.20 (0.11–0.47)
	KOOS: Symptoms and Stiffness	32.3 (3.5–100)	21.5 (0.0–35.8)	- 0.6 [(−1.2) – (−0.1)]	< 0.05	0.02	0.08 (0.06–0.21)
	KOOS: Daily living	29.5 (5.7–78.3)	20.5 (0.0–32.0)	- 1.7 [(−2.8) – (−0.6)]	< 0.01	0.15	0.29 (0.02–0.52)
	KOOS: Sports and recreation	25.0 (5.0–100.0)	10.0 (3.0–27.0)	- 1.3 [(−2.3) – (−0.2)]	< 0.05	0.06	0.23 (0.01–0.42)
	KOOS: Quality of life	20.9 (6.3–68.8)	8.6 (3.0–31.3)	- 0.9 [(−1.7) – (−0.2)]	< 0.05	0.04	0.23 (0.06–0.39)
	Numeric rating scale	7.0 (1.0–9.0)	3.0 (1.0–8.0)	- 0.2 [(−0.3) – (−0.1)]	< 0.001	0.21	0.42 (0.23–0.58)

KOOS: Knee injury and Osteoarthritis Outcome Score; NRS: Numeric Ratings Scale; HADS-A: Hospital Anxiety and Depression Scale – subscale Anxiety; HADS-D: Hospital Anxiety and Depression Scale – subscale Depression