Related Experiment Video
Updated: May 7, 2026

The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials
Published on: April 19, 2024
Review of mixed treatment comparisons in published systematic reviews shows marked increase since 2009
1Department of Continuing Education, University of Oxford, Rewley House, 1, Wellington Square, Oxford OX1 2JA.
Objectives:
To identify and summarize published systematic reviews that report results of meta-analyses that combined direct and indirect comparisons.
Study Design And Setting:
Narrative review of mixed treatment comparisons (MTCs) reported in systematic reviews of health interventions. MEDLINE, MEDLINE In-Process, Embase, CINAHL, DARE, the Cochrane Database of Systematic Reviews, and SIGLE were searched for reviews published up to June 2012 in which a meta-analysis had been conducted that combined direct and indirect comparisons among more than two interventions.
Results:
Reviews reporting MTCs are difficult to identify when searching major databases. These databases offer no way to identify MTCs, and authors use various names when reporting them. Of the 201 eligible reviews identified, more than three-quarters had been published in full. MTC methods have been used to study a wide range of clinical topics. The reported use of these methods has increased rapidly since 2009, and results from MTCs are commonly used in health policy decisions, through the evidence considered in health technology assessments.
Conclusion:
In view of the increasing use of MTCs, indexing of this study type in databases and a consensus on terminology and standards for conduct and reporting would be timely.
Related Concept Videos
Hazard Ratio
For example, in a clinical trial evaluating a...
Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs
Clinical Trials
There are four phases in a clinical trial. A phase one...
Clinical Trials: Overview
Cancer Therapies
However, cancer treatments can pose several challenges, as therapies used to kill cancer cells are generally also toxic to normal cells. Moreover, cancer cells mutate rapidly and can develop resistance to chemical agents or radiation therapy. Besides, all types of cancer cells may not respond to the same therapy. Some cancer cells respond to one...
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...