Here is something the eCOA industry rarely says plainly, the problem with eCOA errors is that they’re common. From our experience of over 20 years, error rates in migrated instruments routinely run at 10–15%. On some projects, we have seen that reach 30–40%. Newly validated text usually fares better but is not immune to errors.
The errors themselves vary. Some are critical: missing content, duplicated response choices, logic failures. Some appear minor: a typo, a mismatched label. Some are embarrassing: an isolated “back” button translated as the body part, “voiding” translated as “on an empty stomach” and confusion around the term “digital”.
In a validated instrument, any difference matters. Nothing is there by accident. Nothing can be changed without consequence.