Correction to: Trials 22, 582 (2021)

https://doi.org/10.1186/s13063-021-05494-0

Following the publication of the original article [1], we were notified that Tables 3 and 4 were identical.

Originally, Table 3 was published as a copy of Table 4. This has now been corrected.

Table 4 remains unchanged.

The original article has been corrected.