gms | German Medical Science

Background/research question: In 2017 the Dachverband Osteologie (DVO) published an S3-Guideline on the prophylaxis, diagnosis, and therapy of osteoporosis. The guideline is an update of the 2014 version and incorporated the 2015 Scottish Intercollegiate Guidelines Network (SIGN) Osteoporosis guideline, with update searches for 2014-16 in accordance with AWMF-methods.

We aimed to determine what evidence was used for the recommendations on bisphosphonates and communicate this information with clinicians practicing in the field of osteology using the publicly available guideline documents.

Methods: We extracted the cited studies from the 2017-DVO guideline, the 2015 SIGN guideline, and update searches into a table using MS Excel. We also accessed an appendix of the DVO Guideline with evidence tables for the studies from the update search. We noted the study type and evidence grade for each citation.

Results: We detected 72 individual citations for effectiveness and 62 for adverse events. The 2017 guideline contained 5 explicit recommendations on bisphosphonates, but because the 2014 DVO-guideline had not used evidence tables, we could only access information regarding the number and types of participants, the nature of the interventions (including dosing) and the outcomes reported for the 12 citations from the update search. For the remaining citations we were forced to rely on the title and the reported evidence grade. To provide an interpretation of the evidence we switched to use a “best-available evidence” approach and extracted results from the studies with the best quality rating and position in the evidence hierarchy.

Conclusions: In conclusion, it was not possible to access a summary of clinically relevant aspects of the body of evidence behind the recommendations using only the publicly available guideline and supporting documents (e.g. the number and size of studies, follow up, type of participants, outcomes, and balance between benefits and harms). Because the guideline was an update, the methods regarding the integration and quality-rating of evidence were mixed (SIGN, Oxford, few evidence tables) and no summary of findings tables or GRADE evidence profiles were available. This example demonstrates the difficulties of updating guidelines and the advantages of a “living guideline” approach with electronic/digital capabilities of integrating new evidence as well as the barriers between guideline producers and clinicans who seek to understand the evidence behind recommendations.

Competing interests: Kylie Thaler is a member of the GRADE-Working Group and formerly Deputy Director of Cochrane Austria.

Anna Glechner and Gernot Wagner are academic staff members at the Department of Evidence-based Medicine and Clinical Epidemiology in Krems, Austria and therefore affiliated with Cochrane Austria.