Table 1 Item difficulty, Rasch fit statistics for each item ( N = 236)

Physical

12.18 (1.92)

-

-

-

Ph1: Pain and discomfort

2.57 (1.00)

-0.11

1.77

1.89

Ph2: Medication

2.62 (1.00)

-0.81

1.56

1.66

Ph3: Energy and fatigue

3.18 (0.87)

0.42

0.67

0.67

Ph4: Mobility

3.62 (0.84)

-0.53

0.88

0.81

Ph5: Sleep and rest

2.99 (1.00)

0.80

0.93

0.95

Ph6: Activities of daily living

3.31 (0.79)

0.15

0.47

0.46

Ph7: Work capacity^a

3.35 (0.94)

0.08

0.77

0.73

Psychological

12.33 (2.47)

-

-

-

Ps1: Positive feelings

2.43 (1.01)

1.50

1.16

1.17

Ps2: Spirit/ religion/ beliefs

3.16 (1.12)

-0.04

0.92

0.82

Ps3: Think

3.16 (1.00)

-0.04

0.71

0.69

Ps4: Body image

3.54 (0.94)

-0.91

1.08

1.04

Ps5: Self-esteem

3.36 (0.89)

0.78

1.01

0.98

Ps6: Negative feelings ^a

2.84 (0.97)

-0.03

1.56

1.63

Social

12.98 (3.00)

-

-

-

S1: Personal relationship

3.39 (0.81)

-0.51

0.87

0.89

S2: Sexual activity

3.03 (1.02)

0.72

1.01

0.98

S3: Social support

3.38 (0.94)

-0.48

1.20

1.11

S4: Being respected^a

3.17 (0.91)

0.27

0.81

0.76

Environment

12.89 (2.65)

-

-

-

E1: Safety and security

3.25 (1.01)

-0.02

1.08

0.99

E2: Physical environment

3.24 (0.94)

0.01

1.05

1.05

E3: Financial resources

2.43 (1.06)

1.76

0.99

0.97

E4: Information acquiring

3.01 (0.98)

0.51

0.84

0.83

E5: Leisure activities

3.00 (1.01)

0.55

1.05

1.06

E6: Home environment

3.55 (0.79)

-0.76

0.77

0.73

E7: Health services

3.53 (0.85)

-0.72

1.14

1.16

E8: Transportation

3.42 (0.82)

-0.43

0.90

0.86

E9: Eating^a

3.60 (0.86)

-0.90

1.12

1.14