An observational study of missing data inquiry from randomized trial authors showed a poor response

Area of Science:

• Medical Research Methodology
• Evidence Synthesis
• Data Management in Clinical Trials

Background:

• Inadequate reporting in randomized controlled trials (RCTs) can impact meta-analysis quality.
• Author data requests are crucial for verifying information in systematic reviews.
• Previous investigations into author response rates for data retrieval are limited.

Purpose of the Study:

• To quantify the results of author data requests for randomized controlled trials (RCTs) included in meta-analyses.
• To identify factors associated with author response rates.
• To propose strategies for improving data retrieval from RCT authors.

Main Methods:

• Authors of 116 RCTs from 4 meta-analyses were contacted via email post-feasibility trial.
• Data accuracy checks and requests for missing data were performed.
• Univariable and multivariable analyses examined associations between response and study characteristics.

Main Results:

• Overall response rate was 41% after initial contact and a reminder.
• Only 7.8% of RCTs had data confirmed or supplemented.
• No significant association found between response and study characteristics.

Conclusions:

• Contacting RCT authors for data verification yields low task completion despite fair response rates.
• A culture of data sharing among researchers is essential for improving evidence synthesis.
• Further research is needed on alternative incentives for data sharing.