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. 2024 Jan 22;8:9. doi: 10.1186/s41687-024-00685-0

Table 2.

Anchor- and distribution-based estimates for the SF-36v2, FACIT-fatigue, and RASIQ

Anchor-based
WPMI
estimates 		Distribution-based estimates Reliabilityi
Anchor N Mean 95% CI SRM Sensitivity Specificity 0.5 SD RCI(80)
SF-36v2 scale (0–100 scoring)
PF PtGAa 120 24.5 21.1, 28.0 1.27 0.78 0.56 9.8 12.7 0.87
RP PtGAa 120 24.5 20.6, 28.5 1.37 0.77 0.58 9.1 10.7 0.89
BP PtGAa 120 25.4 21.9, 28.9 1.65 0.80 0.43 7.6 11.1 0.84
PAINb 125 26.6 23.3, 29.9 1.73 0.87 0.47
GH PtGAa 120 13.6 10.8, 16.4 0.87 0.74 0.45 8.2 16.7 0.68
VT PtGAa 120 21.5 18.2, 24.8 1.30 0.75 0.50 8.3 13.1 0.81
AN5c 60 23.3 18.7, 28.0 1.41 0.71 0.55
SF PtGAa 120 20.5 16.3, 24.7 0.98 0.66 0.51 10.5 19.7 0.74
RE PtGAa 120 16.9 12.9, 21.0 0.70 0.68 0.45 12.4 12.1 0.93
MH PtGAa 120 14.3 11.3, 17.3 0.75 0.69 0.53 9.5 13.3 0.85
SF-36v2 summary (NBS scoring)
PCS PtGAa 120 9.7 8.3, 11.1 1.47 0.83 0.47 3.4 4.1 0.89
MCS PtGAa 120 7.6 5.8, 9.4 0.70 0.66 0.50 5.4 6.0 0.91
FACIT-Fatigue (0–52 scoring)
Fatigue SF-36 PGISd 120 11.3 9.7, 12.9 1.15 0.81 0.52 0.92
PtGAa 80 9.7 8.1, 11.4 0.99 0.75 0.58 4.9 4.9
VT03e 74 11.1 9.4, 12.9 1.13 0.85 0.55
RASIQ (0–100 scoring)
Joint pain SF-36 PGISd 66 -24.0 -28.4, -19.7 -1.34 0.73 0.56 9.1 -6.8 0.96
PtGAa 104 -31.0 -34.6, -27.5 -1.70 0.94 0.49
PAINb 97 -32.7 -36.2, -29.3 -1.80 0.94 0.51
BP01f 71 -21.7 -25.4, -18.0 -1.21 0.84 0.58
Joint stiffness PGISd 66 -23.3 -27.4, -19.1 -1.31 0.73 0.62 9.1 -13.1 0.84
PtGAa 104 -26.1 -29.8, -22.3 -1.44 0.83 0.47
Impact SF-36 PGISd 66 -21.0 -24.5, -17.4 -1.35 0.89 0.48 7.8 -12.8 0.80
PtGAa 104 -21.1 -24.3, -17.9 -1.35 0.93 0.44
AN2g 70 -17.4 -20.7, -14.0 -1.12 0.85 0.57
AN1h 61 -17.8 -21.7, -13.8 -1.14 0.79 0.58

a‘Considering all the ways your arthritis has affected you, how active do you feel your arthritis is…’. Improvement: a decline of 18 points or more

b‘How much pain are you currently having because of your rheumatoid arthritis?’ Improvement: a decline of 20 points or more

c‘I have energy’. Improvement: an increase of 1 point on a 5-point Likert scale

d‘In general, would you say your health is…’. Improvement: an increase of 1 point on a 5-point Likert scale

e‘How much of the time during the past 4 weeks did you feel worn out?’ Improvement: an increase of 1 point on a 5-point Likert scale

f‘How much bodily pain have you had during the past 4 weeks?’ Improvement: an increase of 1 point on a 5-point Likert scale

g‘I feel tired’. Improvement: an increase of 1 point on a 5-point Likert scale

h‘I feel listless (washed out)’. Improvement: an increase of 1 point on a 5-point Likert scale

iCronbach’s alpha, except for SF-36v2 summary scores (PCS, MCS), where reliability is estimated using a method that accounts for the reliability of each score as well as covariances among the scores

AN: anchor; BP, bodily pain; CI: confidence interval; FACIT-Fatigue: Functional Assessment of Chronic Illness Therapy-Fatigue; GH: general health perceptions; MCS: Mental Component Summary; MH: role limitations due to emotional problems; PAIN: Patient’s Assessment of Arthritis Pain; PCS: Physical Component Summary; PF: physical functioning; PGIS: Patient’s Global Impression of Status; PtGA: Patient’s Global Assessment of Disease Activity; RASIQ: Rheumatoid Arthritis Symptoms and Impact Questionnaire; RCI(80): reliable change index based on 80% confidence interval; RE: role limitations due to emotional problems; RP: role limitations due to physical health; SD: standard deviation; SF: social functioning; SF-36v2: Short-Form 36 Health Survey version 2; SRM: standardized response mean; VT: vitality; WPMI: within-patient meaningful improvement