As has been pointed out by
@trickydick this was a convenience sample and not representative of the pool of all applicants. This is quite obvious in that we have 82.9% who report being admitted to at least one medical school – almost twice the national average. It could be that SDN forum readers are far more successful than the typical applicant or that those who were unsuccessful are too ashamed to report, even in an anonymous survey.
In any case, the question holds, is a lack of an interview invitation by Thanksgiving spell doom for an applicant and signal the need to prepare for another cycle?
There is a statistically significant difference in the proportion of applicants who had interview invites before Thanksgiving who were eventually admitted and the proportion of applicants who were not invited until after Thanksgiving who eventually got invites. (p< 0.01) Does this mean that after Thanksgiving interview invites are for the waitlist? I do not believe that to be the case.
Of the 392 respondents who reported having at least one offer of admission, 357 (91%) had an interview invite before Thanksgiving. But what of the flip side? What proportion of those without interview invites before Thanksgiving ended up needing a “Plan B”? Only 65 responders reported having had no invitations before Thanksgiving and 30 (46%) ended up empty handed. As pointed out, it could be that those who had no offers are ashamed to report and that proportion is in reality far larger. The other group to concern ourselves with are the 12% (51/408) who were interviewed before Thanksgiving but ended up empty handed. In fact, that group who might have felt reassured by having an interview before Thanksgiving end up being the most tragic group, particularly if they end up waitlisted and waiting well into the summer, hoping to avoid a reapplication cycle but knowing that the longer they wait, the less successful that cycle may be.
The odds of getting an offer if you have an interview before Thanksgiving are better than the odds of getting an offer if you have no interviews before Thanksgiving. On the other hand, until you have an offer, you have to be continually thinking of how you might improve your application if another cycle is required.