Table 4

 Relative risks (95% CI) for baseline prevalence, prevalence (repeated measures) on two surveys, and one-year cumulative incidence of UE MSD cases on physical examination, among non-cases at baseline; workers with exposure ratings on both surveys, two automobile manufacturing plants, Detroit, MI

PrevalenceCumulative incidence
Baseline only (n = 714)Both surveys: repeated measures (n = 1855)*Follow up survey (n = 470)
*GEE log-link model also included terms for year of survey (p = 0.81) and interaction of exposure index × year (p = 0.20).
Ergonomic exposure index (quartiles)1.3 (1.1 to 1.5)1.3 (1.2 to 1.4)1.2 (0.9 to 1.6)
UE injury (yes/no)1.2 (0.9 to 1.6)1.1 (1.0 to 1.3)1.4 (0.8 to 2.3)
Gender (male/female)1.7 (1.2 to 2.2)1.6 (1.4 to 1.9)2.0 (1.1 to 3.6)
Systemic disease (yes/no)1.4 (1.1 to 1.9)1.4 (1.2 to 1.6)1.0 (0.5 to 1.9)