Intended for healthcare professionals

  1. Research
  2. Bah humbug!...
  3. Bah humbug! Association between sending Christmas cards to trial participants and trial retention: randomised study within a trial conducted simultaneously across eight host trials
CCBY Open access
Research Christmas 2021: Trading Places

Bah humbug! Association between sending Christmas cards to trial participants and trial retention: randomised study within a trial conducted simultaneously across eight host trials

BMJ 2021; 375 doi: https://doi.org/10.1136/bmj-2021-067742 (Published 14 December 2021) Cite this as: BMJ 2021;375:e067742

Linked Editorial

Retaining trial participants takes more than a Christmas card

Data supplement

Related articles

EditorialRetaining trial participants takes more than a Christmas card

See more

Back to top