How prospective trial registration can prevent selective outcome reporting and salami slicing?

Background: Pre-registration of a clinical trial before the first participant is recruited can help to prevent selective outcome reporting and salami-slicing that can distort the evidence base for an intervention and result in people being offered care or treatment that is not effective. Rates of clinical trial registration in nursing and midwifery are low.

Aim: To use a hypothetical example from midwifery practice to illustrate how selective outcome reporting and salami-slicing can distort the evidence base.