Correction to: ED50 of Propofol Combined with Nalbuphine on the Sedative Effect in Painless Hysteroscopy

Correction to: Pain Ther (2021) 10:1235–1243 10.1007/s40122-021-00280-x

In the sentence beginning “From January to March 2020,…” under section “Participants” under heading “Methods” in this article, the year “2020” should have read 2021. The correct sentence should read as: From January to March 2021, we recruited 61 patients aged 18–60 years with American Society of Anaesthesiologists (ASA) physical condition I or II to undergo elective hysteroscopy and therapeutic surgery at the First Affiliated Hospital of Anhui Medical University.