Measuring outcomes in complicated intra-abdominal infections

Complicated intra-abdominal infections (cIAIs) are associated with significant morbidity and mortality. Clinical trials should help guide and improve the management of cIAIs. However, inappropriate selection or measurement of outcomes in cIAIs clinical trials can lead to misleading results on the effectiveness of interventions. This review aims to describe how outcomes are reported in randomized controlled trials evaluating antibiotic treatment for cIAIs and discuss how outcome reporting may be improved.

Commonly used primary outcomes are treatment success or failure, and these outcomes are endorsed by regulatory bodies. However, a consensus objective definition of either is not available and current measures are prone to bias. Variation exists in timing of outcome evaluation and analysis populations, which can lead to further bias. Use of core outcome sets can help standardize outcome reporting.

Inconsistency in outcome selection and reporting can lead to misleading results and impedes meta-analysis of data. Further progress, engaging clinical trialists, regulatory authorities, clinicians and patients is required to achieve consensus on which outcomes should be reported and how and when to measure them.