March 2019 Core Algorithm Update

On March 12th, 2019, Google rolled out its first major algorithm update of the year called the March 2019 Core Update.

The update was intended to introduce incremental changes to Google’s organic search algorithm. The result has been a significant impact on websites related to sensitive topics, particularly those dealing with health.

It was, however, a broad update, meaning multiple changes to the algorithm are bundled up into one major rollout, so the update impacted many industries and niches, not just medical websites.

What Changed?

While Google hasn’t detailed what exactly has changed, the general consensus is that the update primarily deals with a site’s expertise, authority and trust scores, specifically in industries that deal with lifestyle topics.

For example, health sites, eRetailers, local/national news and review sites saw heavy volatility. The main winners were sites with a strong brand profile and broad topical interest, which means niche websites with less brand recognition saw the biggest losses.

One analysis from SearchMetrics showed a correlation between user signals and rankings.

search metrics

While engagement signals may be a factor, it’s likely these metrics are simply correlated with the trust factors mentioned earlier.

  • Does the content match the searcher’s expectation?
  • Is the searcher’s answer easy to find within the content?
  • Is the content written by an expert?
  • Is the brand or author mentioned or cited on other sites in the niche?

More than anything, this update is an evolution in a series of similar updates that happened in 2018, the Core March 2018 Update and Medic Update. As such, many of the sites that were affected by those updates were also impacted by this update, as Google fine-tuned the scoring that affected those sites and as many of those sites adjusted their content quality after the 2018 updates.

How Strong was the Impact?

This update was a big update, but not the biggest Google has ever done.

Several rank tracking providers track volatility in the rankings, which helps measure algorithm updates. The example below show March 12 and 13 as quite volatile, with smaller updates late February.

rank ranger

Top 10 Winners

search metrics

Top 10 Losers

search metrics


March 2019 Core Update was a major update impacting primarily content heavy websites. The update was a fine tuning of previous updates that intended to improve the ranking of trusted authors and established brands.

Google’s Page Quality Rating guideline is thought to be the model which this algorithm hopes to get closer to emulating, and thus should be the primary evaluation criteria for optimizing a website to perform well with future, similar update.

Want to stay up-to-date with the latest news, insights, & more from Catalyst?
Join our newsletter today!