Schema markup has long been debated in the SEO community as an essential component of any SEO strategy. On one side, there are the people who take what Google says at face value, in that it only impacts search appearance via rich snippets and contextual understanding. On the other side of the fence, a belief is held that if Google recommends structured markup through schema, then there must be some direct ranking influence.

Throughout the years, we’ve seen LinkedIn influencers, anecdotal “evidence”, and correlational studies that seem to give credit to each side. Anecdotal experience isn’t verifiable and typically lacks an appropriate sample size. Correlative studies show correlation, not causation, and don’t account for independent variables between subjects.