Evaluation of joint awareness after acetabular fracture: Validation of the Forgotten Joint Score according to the COSMIN checklist protocol

Table 1 Patient characteristics at initial assessment (T1)

n = 100	Total
Sex	21 female/79 male
Mean age at follow up T1	57.9 ± 17.6 yr
Intra-articular step	54 > 3 mm/46 < 3 mm
Treatment	78 operative/22 conservative
Approach (open reduction only)	37 anterior/18 posterior
FJS	41.4 ± 29.7
WOMAC-VAS	60.6 ± 63.3
EQ-5D Index	0.90 ± 0.09
EQ-5D VAS	67.8 ± 23.0
TAS	3.6 ± 1.8

FJS: Forgotten Joint Score; WOMAC-VAS: Western Ontario and McMaster Universities Osteoarthritis Index-Visual Analog Scale; EQ-5D: EuroQol-5D; TAS: Tegner Activity Scale.

Table 2 Detailed data on correlation of functional scores indicating a positive rating for convergent validity (r = Spearmen’s rank correlation coefficient) level of significance P < 0.05

FJS	WOM I	WOM II	WOM III	WOM total	EQ Index	EQ VAS	TAS
r	-0.69	-0.68	-0.70	-0.73	0.72	0.60	0.56
P value	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001
n	96	96	96	96	96	95	94

FJS: Forgotten Joint Score; WOM: Western Ontario and McMaster Universities Osteoarthritis Score; EQ: EuroQol-5D; VAS: Visual Analog Scale; TAS: Tegner Activity Scale.

Table 3 Responsiveness of the Forgotten Joint Score based on the subjective rating of change

	n	FJS first assessment		FJS second assessment		Difference FJS first-second assessment		P value	SEM	SDC	ES
		m	SD	m	SD	m	95%CI
Function improved	21	46.9	34.1	56.2	34.9	-9.4	-13.6–(-5.1)	0.001			0.28
Function unchanged	24	43.8	31.6	42.7	32.6	1.1	-1.9–4.1	0.743	3.2	8.8	0.03
Function worsened	10	37.7	29.0	20.2	13.1	17.1	0.7–33.4	0.016			0.59

FJS: Forgotten Joint Score; SEM: Standard error of measurement; SDC: Smallest detectable change; ES: Effect size.