Rationale At the request of a Dutch governmental organization, a multidisciplinary group of osteoporosis experts in the Netherlands published in 2002 a guideline on case finding, diagnosis, prevention and treatment of osteoporosis. These guidelines were evaluated for their validity and applicability. Methods Analysis by 5 external osteoporosis experts using the 'Appraisal of Guidelines for Research & Evaluation' ('AGREE') instrument. Results The score for the 6 domains of AGREE was 88% for the scope and purpose domain, 76% for stakeholder involvement, 81% (...) for rigour of development, 84% for clarity and presentation, 77% for applicability and 73% for editorial independence. For single components of the domains of AGREE, highest scores were found for systematic methods used to search for evidence (100%), inclusion of individuals from all the relevant professional groups (95%) and ease of identifying key recommendations (95%). Lowest scores to single components of the several domains were given for piloting among target users (44%). All experts recommended the guidelines for use in practice. Conclusions The AGREE instrument scored high for development, clarity and presentation but low for piloting among target users and implementation. Based on the guideline, algorithms from case finding to treatment were constructed that could be tested for piloting among target users and for implementation of the guideline. (shrink)