A/B Testing is one of the secrets of email successThere are dozens, maybe thousands of articles about ways to motivate consumers to open your medical emails and click on them. Some of the advice is solid. And some of its BS. It's left up to the reader to separate the wheat from the chaff. Going with your gut works out sometimes, and even the rules – keep your subject line short, the first story should echo the subject line, stick to one topic in the subject line – can keep you out of hot water.


If you consistently want to pull better results, you need to conduct A/B or multi-variant tests that pit different subject line variations or content against each other.

Consider all the factors that play into earning that all-important open click, such as the from address, day-of-week, time-of-day, major sporting or entertainment events, and holidays. All the email newsletters we send are optimized for opens and click-thrus differently. Orthopedic surgeons have different email habits than Ophthalmologists. And Ophthalmologists handle their inbox differently from Optometrists. To sum it up, "it's complicated."

Using ourselves as an example, we'll give you an inside look at how we approach email optimization for opens and clicks. We'll be clear about what's conjecture and what is opinion.

Bionews is Biotica's monthly email newsletter (take a sec and signup below!), containing five to eight feature articles and other shorter items. With every issue, we A/B test subject lines and different versions of the content. Content changes may include button sizes and copy, design, headline sizes, link colors, story order, and much more. Bionews aims to drive qualified traffic, from the teaser in our email to the article on the blog. So, the primary metrics we follow are traffic that we've tagged Bionews, the value of that traffic measured by engagement, and the likelihood that the user also visits another page. All in all, we track 15 to 20% of total web traffic from email.

Most of the best practices recommended by the industry work okay, but we squeeze additional results through our A/B tests. On average, our A/B tests can increase the number of clicks from 2 to 31%. Pushing the extra engagement is particularly important for a company with niche markets. Keep testing on a parameter, say button color, until the A/B improvement is just incremental. Plus, if you value engagement the same as search ads, you can show this improvement on your bottom line.

Over ten years of designing, writing, and coding emails, we have a few rules of our own that seem to test out repeatedly. Here are a few examples:

  • Don't write ambiguous subject lines or headlines for stories. When in doubt, use the straight, less fluffy one.
  • Order stories based on what you think will generate the most clicks. Note, this is generally not a message from the board of directors.
  • Place the most compelling words at the front of a headline. For example, "UFOs sighted in the Rocky Mountains" Vs. "Rocky Mountains are possible home to UFOs."
  • Test the type size on any clickable copy.
  • Learn about the words that trigger spam filters.
  • If you get a great result, test it again for confirmation.
  • Don't learn rules. Invent the ones that work for your specific application and audience
backlink techniques

Click-thru Tests

Test: Smaller Headline vs. Larger Headline


Click-thru Rate

A Smaller Headlines: 7% | B Larger Headlines: 12% | Increase in Opens: 5%

Test: Addition of Content


Click-thru Rate

A No new content 3% | B Additional content (healthcare calendar) 23% | Click-thru increase: 20%

More stories above the fold





Click-thru Rate

A Fewer stories: 18% | B More stories: 3% | Click-thru increase: -15%