Google’s December 2020 Core update was significant according to many data providers. Our job is to analyze these updates to understand patterns and advise our clients on improving their websites. Now that the core update has finished rolling out as of December 16, 2020, we’d like to share some interesting observations.
What is a core update?
Google makes changes to their search algorithms daily. A few times a year, they release more noticeable significant changes to their core algorithms and systems. According to Google, core updates are designed to ensure they deliver relevant and authoritative content to searchers.
If your website’s traffic has declined following a core update, Google’s algorithms may have found other pages on the web more relevant and helpful than yours. This can be frustrating as it’s often unclear how Google makes these determinations.
Google’s documentation on How Search Works describes the steps involved in returning relevant results:
1. Organize the content on the web: As Google crawls the web, they organize pages into an index, noting key signals on each page like keywords and freshness.
2. Determine the meaning of the searcher’s query: Google needs to understand the intent behind each query. Algorithms decide if a query requires fresh, new content or if it can be satisfied with existing information. They can present fact-based answers or more comprehensive organic results.
3. Determining which pages are the most helpful to return: Google aims to prioritize web pages that best answer the searcher’s query.
Google has a blog post dedicated to explaining core updates, while offering advice to site owners. Our methodology to diagnose traffic drops often draws from this.
The Quality raters guidelines can give us clues about Google updates
Earlier Google updates often had clear focuses. For example, sites affected by the Penguin algorithm typically had issues with low-quality spammy links, while Panda-affected sites often had thin or unhelpful content.
Core updates usually don’t have one single and obvious focus. If your site was negatively affected, there is rarely a single issue to blame.
The Quality Raters’ Guidelines (QRG) can give us clues on what improvements Google aims for. When these guidelines update, we pay close attention.
Sometimes, the QRG can indicate what Google engineers are working on. For example, in the summer of 2018, Google modified the QRG to add “safety of users” for YMYL pages:
In the same revision of the QRG, Google added that pages with “evidence of mixed or mildly negative…reputation” should be rated as “low”:
We assume these phrases were added so Google engineers could determine whether a site contains harmful information or if an author or business is known for a bad reputation. For instance, medical and nutritional sites with serious reputation issues saw huge ranking reductions following the August 2018 “Medic” update.
Similarly, the June 3, 2019, core update impacted sites offering alternative medical advice that contradicted scientific consensus. Again, this aligns with the QRG:
In October 2020, the QRG was updated with examples showing how to determine if a page meets a searcher’s needs. For instance, a page discussing octaves on a piano was rated lower for a query about guitar octaves.
We suspect that Google is improving at surfacing pages that meet user intent and that Natural Language Processing (NLP) frameworks play a role. However, Danny Sullivan indicated that the December core update was not directly related to BERT:
We speculated that frameworks like BERT, SMITH, or BigBird might be used to analyze longer texts for relevance to search queries. But as we continue to analyze, no definitive answers have emerged. John Mueller of Google even referenced “The Little Prince” to suggest the essential changes might be invisible:
What is essential
is invisible
to the eye.
— ???? John ???? (@JohnMu)
Examples of sites affected by the December core update
Drawing on public data from a study by Lily Ray, here are some examples:
DrAxe.com
This site has been discussed heavily since its drastic decline after the August 1, 2018 core update. It primarily discusses alternative medical topics. Recent data shows gains on many pages after the December core update:
We examined a page that saw significant keyword improvements:
Here are the SERPs for “liver cleanse” before and after the update. DrAxe.com’s page improved from #10 to #4:
It seemed that Dr. Axe’s article met searchers’ needs better, offering practical recipes and steps.
Although this doesn’t fully recover their August 2018 Medic hit, it shows notable improvements. Mercola.com, a similar site, saw drops, indicating a difference in Google’s treatment of alternative medical content.
Medical advice site
This site experienced ups and downs with several updates. Their traffic showed significant hits in the May update without full recovery in December:
We noted individual pages showing varying performance:
This update highlighted a shift: individual keywords showed changes rather than entire sites.
Vaccines.gov
The study indicated Vaccines.gov saw a notable decline. This site saw a boost in June 2020, likely due to Google emphasizing authority in times of crisis. The recent core update might have balanced relevance with authority:
Alternative medical site
We observed improvements for an alternative medical client, indicating Google’s better understanding of less mainstream medical content:
Patterns we are investigating after this update
We are still investigating patterns after this update:
1) Google may have reassessed alternative medical topics. Alt-med clients saw improvements, suggesting Google may be better at identifying trustworthy content in this area.
2) Increased attention to headings and content structure. Effective use of headings correlated with improved rankings.
3) Enhanced content relevance for queries. Even if not BERT-related, Google seems better at surfacing relevant content.
4) Impact of user experience (UX). Sites with excessive ads may have seen declines.
5) Cryptocurrency and user-generated content. We are exploring these areas, noting that user-generated content improved rankings for several clients.
Recovery advice is challenging to provide without pinpointing specific issues. Our approach includes adhering to the Quality Raters’ Guidelines and Google’s Core Updates blog post:
- Read the Quality Raters’ Guidelines and focus on relevant examples.
- Support medical claims with strong references from authoritative sources.
- Be transparent about who you are, who’s responsible for content, refund policies, and monetization methods.
- Examine why competitors’ pages improved for specific keywords.
- Use descriptive headings effectively.
- Use authoritative authors or medical reviewers for content.
- Avoid intrusive ads.
Technical reviews are also recommended, though technical issues are rarely the main cause of traffic drops after a core update.
