Facebook Conversions API match quality for health advertisers: what to send when you can't send much

Here's the paradox for health advertisers. You want good match quality, because that's how Meta ties a conversion to a real person. But you're supposed to send as little as possible, because sensitive data is the whole problem. So can you have both?

Yes, and the answer hinges on understanding what match quality actually depends on. Once you see it, the paradox dissolves.

Matching relies mostly on who the person is and which ad they clicked, not on the page they read. So the things that matter are: a hashed email, a hashed phone, the ad click ID, and, for website events, things like the IP address and user agent. None of those reveal a health condition. They identify a person and a click. That's exactly what matching needs.

What matching doesn't need is the page path, the event name describing the treatment, or the form's medical questions. Those add nothing to matching and a lot to risk. So the recipe is simple to say: send the strong identifiers, drop the descriptive stuff.

Event Match Quality is the 0 to 10 score in Events Manager that rates how well the details you send let Meta find the person. Let me give you the levers, in the order I'd pull them.

First, send both email and phone. Two chances to match instead of one.

Second, clean before you hash. Lowercase and trim the email. Format the phone as digits with the country code. A badly formatted value hashes to something that matches nobody, and the hash looks fine, so nothing tells you it's broken.

Third, include the click ID whenever you have it. It's the strongest single signal for someone who clicked an ad.

Fourth, check the CRM itself. Half-empty contacts and throwaway emails can't match no matter how perfectly you send them.

Notice that none of the four requires sending anything about the patient's health. That's the point. For a health advertiser, match quality is a data hygiene problem, not a data volume problem.

A made-up illustration. Two versions of a booking event. Version A carries the page path, a descriptive event name, the form's "reason for visit", and a hashed email. Version B carries a neutral event name, a hashed email, a hashed phone and the ad click. Version A has more information and matches worse, because the descriptive parts get the event held back and because it's missing the phone and click. Version B has less information and matches better. More isn't better here. The right information is.

One more consideration: consistency. If some events carry a phone and some don't, your match quality will bounce around. Make the forms ask for both, validate the format at entry, and send the same fields every time.

Watch your match quality over time, not just once. When it dips, the causes are usually one of a few things: a form change that made the phone number optional, a new integration that sends a different format, a site update that dropped the click ID capture, or a spike in junk leads with fake emails. Each has a different fix, and you only know which one applies if you noticed the dip near the date it started. A simple habit: look at the score monthly, write it down, and if it falls, check what changed in the weeks before.

What's your match score, and what did you have to give up to get it?

For reference, DataCops sends the click ID plus hashed email and phone with each event, and the delivery log shows whether each one was sent, held, skipped or failed. A low score is usually a CRM data problem, not a sending problem.