The study states: "We studied sera from adults (ages 18 to 55 years) who received two doses of the Moderna mRNA-1273 vaccine in phase 1 clinical trials (12). The majority of our study focused on 14 individuals who received the 250-μg dose, although we validated key conclusions with a smaller subset of eight trial participants who received the 100-μg dose. The sera were collected at 36 and 119 days after the first vaccine dose, corresponding to 7 and 90 days after the second dose."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8369496/

Strange that the study would focus on individuals who received a 250-μg dose. The adult dose is 100-μg (https://reference.medscape.com/drug/mrna-1273-moderna-covid-...). Yes, the study states that key findings were validated with 8 participants who received the regular dosage, but still seems odd to me.

The comparison dataset is explained as: "The convalescent plasma samples were characterized in earlier studies (13–16) and grouped into an early time point of 15 to 60 days after symptom onset and a late time point of 100 to 150 days after symptom onset."

So the comparison was between vaccinated individuals, most of whom received a higher dose than is being given out, to infected individuals, and the time periods don't exactly line up. For the vaccinated dataset, the time periods were 7 and 90 days after the second dose. For the other dataset, the time periods were 15-60 days, and 100-150 days after symptom offset.

Deeper into the study, there is also this: "The escape maps of the 100-μg cohort resembled those of the 250-μg cohort and fell into the 456/484-targeting, core-targeting, or flat categories (fig. S6). Although the sample sizes are small, and a higher fraction of the 100-μg dose escape maps were flat than for the 250-μg cohort (4 of 8 versus 5 of 14, respectively), this suggests that 100- and 250-μg doses elicit antibody responses similar in the breadth of their RBD-binding specificity."