Inadequate reporting of adjudicators in open-label trials of anticancer drugs between 2017 and 2021: a methodological review

Abstract

Objectives: In open-label trials, the details of the adjudicators are essential to evaluate the risk of detection bias. We aimed to describe how the adjudicators of progression-free survival (PFS) and objective response rate (ORR) have been reported in open-label trials of anticancer drugs.

Study design and setting: A literature search was conducted using MEDLINE via PubMed. We included open-label, parallel-group superiority randomized trials that investigated the PFS and ORR of anticancer drugs for solid tumors. After screening based on the titles and abstracts, 200 articles were randomly selected from 2017 to 2021. The researchers independently checked the eligibility and collected the adjudicators' information in the protocol, registry, and original article.

Results: One hundred fifty five studies reported the PFS and ORR. Approximately half of the studies did not report adjudicators (47.7% in PFS and 47.6% in ORR) in the published articles. The inconsistency between the protocol/registry and the published article was 31.0% for PFS and 33.5% for ORR. The prespecified outcomes were not reported in 5.2% of the studies evaluating PFS and 4.5% evaluating ORR.

Conclusion: This methodological review found that adjudicators were poorly and inconsistently reported between the protocol/registry and the final publication in open-label trials of anticancer drugs.

Keywords: Antineoplastic agents; Detection bias; Open-label trials; Outcome adjudicator; Randomized controlled trials; Solid tumors.