Correction to: Trials 22, 736 (2021)

https://doi.org/10.1186/s13063-021-05723-6

Following the publication of the original article [1], we were notified that Figure 4 was not corrected as per the author’s request.

  • Originally published Figure 4

    figure a
  • Corrected Figure 4

    figure 4

The original article has been corrected.