What happened when we followed up on our case studies a year later

We publish a case study with numbers frozen at the moment we interview the subject: a 40% reduction, a 3x improvement, whatever was true that week. We had never gone back to check whether those numbers still held a year later, until we called every subject from one calendar year of published work to find out.

The honest result

Of the fourteen case studies we followed up on, the specific number had held or improved in nine, had regressed partially in four, and in one case the initiative had been quietly discontinued entirely.

Why we published this anyway

The instinct is to bury the four that regressed and the one that failed. We think that instinct is exactly backwards for anyone trying to build trust with a skeptical B2B buyer, who already assumes every case study is cherry-picked.

What we changed as a result

We now add a one-line update to every published case study on its one-year anniversary: still true, partially true with a short explanation, or discontinued. It is a small addition and it has become, by client feedback, one of the more trusted things on their entire site.

• A case study with a visible one-year update reads as more credible than one presented as permanently frozen in time.

• The discontinued case is not deleted; it is left up with an honest note, because deleting it would be more damaging to trust than the original failure.

• We now warn every new case study subject that we will follow up in a year, which appears to make them more careful about the number they claim in the first place.