- Examine whether a finding varies under different conditions
Many interventions work differently for different people or under different conditions. By combining results from different studies, it may be possible to determine how groups of individuals vary in the way they respond to interventions. Understanding this heterogeneity can help target treatments to the right patients.
- Be updated as new information arises
Once researchers have designed a process for gathering and synthesizing relevant information, that process can be easily updated to capture new research. For example, if researchers conduct a systematic review in 2016 comparing bariatric surgery to gastric bypass surgery, they can rerun their search in 2017 to find new studies and update their work.
- Identify research gaps and needs for future studies
Because evidence synthesis takes a comprehensive look at the existing body of knowledge, it captures not only what research already exists but what research is missing. This analysis is helpful for guiding the direction of future studies. For instance, a meta analysis of studies related to the performance of limb prosthesis might find that few studies include women with prosthetic limbs and recommend research examining if performance differs between men and women.
We’ll talk more about how we do this later on in the course. First, let’s discuss the various types of evidence synthesis.