TABLE IV.

Regression Results to Estimate Differences Between the Workers’ Compensation Outcomes Pre- and Post-Intervention by Intervention Major Groups

Intervention major groupa	Number of employersb (%)	Claims per 100 FTEc, intervention effecte,h RR (95% CI)	Cost per FTEd, intervention effectf,h RR (95% CI)	Geometric mean cost per claimd, intervention effectg,h RR (95% CI)
Ergonomic	348 (74%)	0.31 (0.20, 0.48)*	0.17 (0.00, 0.29)*	0.73 (0.59, 0.91)*
Safety	38 (8%)	0.09 (0.02, 0.50)*	0.11 (0.10, 0.13)*	0.78 (0.44, 1.37)
Ventilation	8 (2%)	2.19 (0.86, 5.60)	3.53 (1.65, 5.16)*	2.64 (1.15, 6.08)*
Multiple-purpose	69 (15%)	0.24 (0.12, 0.49)*	0.12 (0.08, 0.15)*	0.52 (0.3, 0.88)*

^aIntervention type determined by consensus rating of two certified professional ergonomists based on case study reviews.

^bNumber of employers in the claim rates analysis and percentage of total employers in parentheses. There were fewer employers in the cost analyses since employers who participated in programs that reduced the apparent cost of the claims by allowing employers to pay portions of the claims were excluded.

^cTotal number of claims (medical-only and lost-time) per100 full-time equivalents (FTEs).

^dPaid 30-month nominal cost.

^ePoisson regression.

^fTwo-part regression model- refer to Methods and Online Appendix.

^gLinear regression.

^hModel does not control for time trend independent of intervention.

^*Significant difference, P <.05.