Table 9. Adjusted Difference in Improvement in Health-Related Quality of Life and Satisfaction after Knee Replacement::A Comparison Between Patients with different Completed Levels of Schooling.

SF36 Sub-Scale	Adjusted Difference Between U+HVE+PHVSE and MVE+PMVE* (95%CI)	Adjusted Difference Between MVE+PMVE and LVE+ES+NFE** (95%CI)	Adjusted Difference Between U+HVE+PHVSE and LVE+ES+NFE*** (95%CI)
Physical Functioning	−5.80 (−15.1–3.53)	−2.24 (−9.14–4.65)	−7.99 (−17.2–1.26)
Role-Physical	−3.37 (−22.5–15.7)	−12.2 (−26.5–2.18)	−16.5 (−35.4–2.53)
Bodily Pain	1.00 (−9.02–11.0)	−6.46 (−14.1–1.20)	−6.13 (−16.1–3.81)
General Health	−4.84 (−11.4–1.72)	−2.84 (−7.88–2.21)	−7.64 (−14.2–−1.10)
Vitality	−0.60 (−7.57–6.36)	3.57 (−1.70–8.83)	2.98 (−3.93–9.89)
Social Functioning	−3.22 (−13.4–6.94)	0.87 (−6.47–8.21)	−2.09 (−12.2–7.94)
Role Emotional	−1.26 (−18.8–16.2)	5.73 (−7.79–19.3)	4.49 (−12.8–21.8)
Mental Health	−0.80 (−6.69–5.08)	5.84 (1.11–10.6)	6.32 (0.53–12.1)
PCS	−1.36 (−4.90–2.18)	−3.42 (−6.04–−0.80)	−5.04 (−8.56–−1.52)
MCS	0.03 (−3.63–3.70)	3.04 (0.19–5.88)	3.58 (−0.03–7.19)
NRS Satisfaction	0.2 (−0.8–1.1)	−0.1 (−0.8–0.6)	−0.1 (−1.0–0.8)

U+HVE+PHVSE: University, Higher Vocational Education and Preparatory Higher Vocational & Scientific Education; MVE+PMVE: Middle Vocational Education and Preparatory Middle Vocational Education; LVE+ES+NFE: Lower Vocational Education, Elementary Schooling and No Formal Education.

^*Negative values indicate a higher mean improvement in HRQoL after TKR in U+HVE+PHVSE patients, compared to MVE+PMVE patients.

^**Negative values indicate a higher mean improvement in HRQoL after TKR in MVE+PMVE patients, compared to LVE+ES+NFE patients.

^***Negative values indicate a higher mean improvement in HRQoL after TKR in U+HVE+PHVSE patients, compared to LVE+ES+NFE patients.

The mean differences between education level are adjusted for age, sex, Body Mass Index and Charnley Classification of Comorbidity and stratified for quartiles of follow-up.