Outcome Reporting Bias in Clinical Trials Researching Disease-Modifying Therapy in Patients With Multiple Sclerosis

Area of Science:

• Clinical Trials Methodology
• Neurology
• Pharmaceutical Research

Background:

• Outcome reporting bias, where trial publication depends on clinical significance, compromises research validity.
• Immunomodulatory drug research for multiple sclerosis (MS) has expanded significantly.
• Assessing outcome reporting bias in MS immunomodulatory drug trials is crucial.

Purpose of the Study:

• To investigate the extent of outcome reporting bias in multiple sclerosis (MS) clinical trials.
• To identify potential factors contributing to this bias in immunomodulatory drug research.

Main Methods:

• Identified MS clinical trials registered on ClinicalTrials.gov (post-Sept 2007, pre-2019).
• Extracted study design, funding, and outcome data from registry.
• Compared registered outcomes with published outcomes to detect discrepancies.

Main Results:

• Of 535 trials, 101 had publications; 95% showed outcome reporting discrepancies.
• 26 publications had discrepancies in primary outcomes; 44% of published secondary outcomes were not registered.
• Late registration and outcome amendments were common; non-industry and open-label trials showed trends towards bias.

Conclusions:

• Selective outcome reporting is highly prevalent in disease-modifying drug trials for MS.
• Strategies to mitigate outcome reporting bias are needed to improve research integrity.