When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
In the absence of direct comparative data, indirect comparisons may provide valuable information. For example, if two different interventions have been evaluated against a common comparator, the relative effects of the two interventions compared with each other can be estimated indirectly.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.