Reasons for Downgrading the Certainty of Evidence for Indirectness in Synthesis of Surgical Procedures for Patients With Fractures: A Meta-Research Analysis

Abstract

Rationale

Indirectness occurs when the synthesized evidence may not be directly applied to the relevant clinical context. A common argument used by surgeons is that evidence that arises from clinical trials is limited due to a lack of fidelity regarding surgery techniques, materials, and surgeon and center experience. Considering that there are many particularities in surgical interventions for the treatment of bone fractures, diverseness is expected among trials that randomized patients to compare surgical procedures. An in-depth analysis of how this expected diverseness is reflected in indirectness judgments on the certainty of synthesized evidence is lacking.

Aims and Objectives

To analyze the certainty of evidence from all Cochrane reviews of surgical interventions for the treatment of patients with bone fractures and the reasons for indirectness downgrading.

Method

A meta-research analysis of all Cochrane systematic reviews that compare any surgical interventions in patients with any type of bone fracture. A sensitive search was conducted in the Cochrane Database of Systematic Review from inception to 16 October 2024.

Results

The certainty of the evidence of all Cochrane reviews of surgical interventions for patients with fractures is very low or low in 66.5% of eligible outcomes. Indirectness contributed to the certainty downgrade in only 12.26% of outcomes (26/212), and of those, the indirectness was related to the intervention in 11.5% (4/26). The results show that although the certainty of evidence of surgical interventions for patients with fractures is usually downgraded, indirectness is not a common cause of concern.

Conclusion

The certainty of evidence for surgical interventions in patients with fractures is typically downgraded, often to very low. However, indirectness is not a common reason for such downgrading. The anticipated diverseness regarding surgery techniques, materials, and surgeon and center experience was not impactful in the overall certainty of evidence in the Cochrane reviews that were included.