Meta-analysis and Network meta-analysis

Meta-analysis (MA) and Network meta analysis
Aim: To estimate the relative effectiveness and/or safety of two products
Application: To combine multiple evidence sources into a single estimate of efficacy and/or safety
Identifies: Which product or Which of a set of products is most efficacious/safe for use in the analysed setting
Informs: Value messaging, product positioning, and sales strategy
Meta-analysis
In most settings, healthcare providers and payers can select their product of choice from multiple available options. Each of these products is usually backed by positive clinical data, so the question becomes which product is backed by the most evidence and the most robust evidence. This question can be answered via a MA.
MA is viewed as some of the highest levels of clinical evidence available and their outcomes are likely to publishable. It takes data from multiple randomized, controlled trials and synthesises the estimates of effectiveness from each individual trials into an overall estimate of effectiveness. Using MA, multiple trials showing non-significant or only minor benefits may result in a significant difference between products as the power of the individual studies is magnified. Alternatively, the significant benefit observed in a few trials may be outweighed by multiple trials showing no difference between products.
For further details on MA please contact us or consult:
- Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. Mother et. al, 2009.
- The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration. Liberati et. al, 2009.
- Systematic review or MA? Their place in the evidence hierarchy. Paul and Leibovici 2013.
- Systematic review and MA methodology. Crowther et. al, 2010.
Network-meta-analysis:
Healthcare providers and payers can often select their product of choice from multiple available options. As each of these products is usually backed by positive clinical data, so the question becomes which product is backed by the most evidence and the most robust evidence. This question can be answered via a network-meta-analysis.
Network-meta-analysis is viewed as some of the highest levels of clinical evidence available. It takes data from multiple randomized, controlled trials and synthesises the estimates of effectiveness from each individual trials into estimates of head-to-head effectiveness. Using network-meta-analysis, a probability of superiority per product can be calculated. As with MA, multiple trials showing non-significant or only minor benefits may result in a significant difference between products as the power of the individual studies is magnified.
In a network-meta-analysis, multiple treatments (three or more) are being compared using both direct comparisons and indirect data. Indirect data are linked via a common comparator, e.g. the standard of care or control arm. If an analysis considers the efficacy and safety of two products only connected via indirect data, this is known as an indirect treatment comparison rather than a network- meta-analysis. Network-meta-analysis and indirect treatment comparison are statistically complex and involve Bayesian analysis. When compared with standard MA, this can make their outcomes more difficult to communicate effectively. The likelihood of publication, though, is also high and these studies are of interest to physicians as well as healthcare payers and providers.
Further Reading:
- Interpreting Indirect Treatment Comparisons and Network-Meta-Analysis for Health-Care Decision Making. Jansen et. al, 2011.
- Conducting Indirect-Treatment-Comparison and Network-Meta-Analysis Studies. Hoaglin et. al , 2011.
- Network-meta-analysis. Tianjing Li et. al, 2011.
