Implementation of a guideline for low back pain management in primary care: a cost-effectiveness analysis.

STUDY DESIGN: Cost-effectiveness analysis alongside a cluster randomized controlled trial.

OBJECTIVE: To study the cost-effectiveness of 2 low back pain guideline implementation (GI) strategies.

SUMMARY OF BACKGROUND DATA: Several evidence-based guidelines on management of low back pain have been published. However, there is still no consensus on the effective implementation strategy. Especially studies on the economic impact of different implementation strategies are lacking.

METHODS: This analysis was performed alongside a cluster randomized controlled trial on the effectiveness of 2 GI strategies (physician education alone [GI] or physician education in combination with motivational counseling [MC] by practice nurses)--both compared with the postal dissemination of the guideline (control group, C). Sociodemographic data, pain characteristics, and cost data were collected by interview at baseline and after 6 and 12 months. low back pain-related health care costs were valued for 2004 from the societal perspective.

RESULTS: For the cost analysis, 1322 patients from 126 general practices were included. Both interventions showed lower direct and indirect costs as well as better patient outcomes during follow-up compared with controls. In addition, both intervention arms showed superiority of cost-effectiveness to C. The effects attenuated when adjusting for differences of health care utilization prior to patient recruitment and for clustering of data.

CONCLUSION: Trends in cost-effectiveness are visible but need to be confirmed in future studies. Researchers performing cost-evaluation studies should test for baseline imbalances of health care utilization data instead of judging on the randomization success by reviewing non-cost parameters like clinical data alone.