Table 4.

Associations between baseline workplace sitting in 2012 and complaint of upper back and the lower back in the last 12 months in 2017 (yes/no) stratified by sex to baseline among 2,082 employees aged 31–60 years in Germany. Poisson regressions. Prevalence Ratios (PR).

Exposure	Strata defined by sex prior to baseline
Occupational sitting 2012	Upper back, n = 635				Lower back, n = 1177
	Men		Women		Men		Women
	PR	95% CI	PR	95% CI	PR	95% CI	PR	95% CI
Model 3
Under 5 h/week	1	(Ref)	1	(Ref)	1	(Ref)	1	(Ref)
5 to < 15 h/week	1.20	0.88–1.63	1.07	0.85–1.35	1.04	0.89–1.21	1.01	0.87–1.18
15 to < 25 h/week	1.15	0.79–1.66	1.25	0.99–1.59	1.13	0.95–1.34	1.13	0.97–1.32
25 to < 35 h/week	1.20	0.81–1.77	1.05	0.79–1.40	1.03	0.84–1.26	1.15	0.96–1.38
35 or more hours/week	1.08	0.74–1.59	0.75	0.52–1.07	1.00	0.83–1.21	1.03	0.84–1.27

Model 3: adjusted for age, occupational level, BMI, smoking, musculoskeletal diseases at baseline, psychological disorders, lifting/carrying heavy loads at work and leisure time physical activity

PR: prevalence ratio, Ref: reference category