Understood. But, sorry, we do NOT obfuscate or erase their posts. Edgeryders’s TOS are very clear as for that. What we do is not use their content for this research.
The 6 unreachable ones are most likely people who changed their email address in between. These are not people that were involved with opencare in the last two years; rather, people who had in previous years posted content that we found consistent with the opencare research questions. Edgeryders admits the use of one-time email addresses, but no one uses them that I know of. And, if we want to be fastidious about it, all posting in ER is anonymous, as we do not enforce, nor even recommend, a real name policy.
As for the question about why five people denied consent, I will leave the answer to @noemi.