Browse the glossary:

• lead-time bias
  — An apparent increase in survival due to detecting a health condition such as cancer at an early stage, when there is no actual effect on survival, just a longer period with the diagnosis.; … (read more)
• length-time bias (length bias)
  — In screening, an apparent increase in survival due to detecting disease earlier than it would otherwise have been detected; … (read more)
•   level of evidence (hierarchy of evidence)
  — An indication of where a type of study lies in a hierarchy of evidence, based on the risk of bias; … (read more)
• likelihood (probability, risk)
  — The probability that an event, association, or difference will occur in a study or in practice; … (read more)
• likelihood ratio
  — A measure of the accuracy of a screening or diagnostic test; … (read more)
• loss to follow-up (attrition, drop-outs)
  — The loss of participants during the course of a study; … (read more)
• low certainty of the evidence (low confidence in the effect estimate, low quality of the evidence, low strength of the evidence)
  — The research provides some indication of the likely effect. However, the likelihood that the actual effect will be substantially different is high; … (read more)
• low risk of bias (internal validity)
  — In studies of treatment effects, the extent to which the design and conduct of a study eliminates or reduces bias; … (read more)