Table 4 Adjusted mixed model analysis with low back pain as dependent variable, stratified on gender

Tobacco status

 No

Ref

Ref

 Yes

0.07

0.43

−0.11

0.26

0.08

0.34

−0.08

0.24

Education/profession^a

 Electrician/Hairdresser

Ref

Ref

 Media/Design

0.04

0.82

−0.29

0.36

0.07

0.48

−0.12

0.27

Age

0.05

0.57

−0.13

0.23

0.06

0.13

−0.02

0.14

Ethnicity

 Non-western

Ref

Ref

 Western

−0.20

0.33

−0.61

0.21

−0.04

0.787

−0.31

0.23

Socioeconomic background

 Low

Ref

Ref

 Moderate/high

0.19

0.31

−0.17

0.56

−0.08

0.54

−0.34

0.18

Physical activity level

 Low

Ref

Ref

 Moderate/high

−0.03

0.73

−0.17

0.12

−0.11

0.06

−0.21

0.01

BMI (kg/m²)

0.01

0.40

−0.02

0.05

0.03

<0.01

0.01

0.06

Work demands

 Low

Ref

Ref

 Moderate

0.02

0.89

−0.28

0.32

0.19

0.16

−0.07

0.46

 High

0.26

0.48

−0.46

0.99

0.23

0.37

−0.28

0.74

Time

 T0

Ref

Ref

 T2

−0.19

0.06

−0.39

0.01

−0.20

0.01

−0.36

−0.04

 T4

−0.32

<0.01

−0.52

−0.13

−0.20

0.02

−0.36

−0.03

 T5

−0.32

<0.01

−0.53

−0.12

−0.24

<0.01

−0.40

−0.07

 T7

−0.34

<0.01

−0.56

−0.12

−0.25

0.01

−0.43

−0.07

 T11

−0.13

0.27

−0.37

0.10

−0.28

<0.01

−0.46

−0.09

 T14

−0.36

<0.01

−0.62

−0.10

−0.53

<0.001

−0.75

−0.32

 T17

−0.34

<0.05

−0.61

−0.07

−0.40

<0.01

−0.62

−0.17

 T20

0.03

0.79

−0.22

0.29

−0.40

<0.001

−0.60

−0.19