Dictionary

The Dictionary provides concise definitions of health economics terms, arranged alphabetically for quick reference. Use it to understand unfamiliar terminology or confirm the meaning of a specific term.

5 terms matching Knot

K

Knot
A specified point along a variable's range at which a spline function is allowed to change shape, used in flexible parametric survival models.
Knot Placement
The methodological decision on where along the time axis to position a spline-based survival model's knots, whether by percentile or clinical judgement.

R

Restricted Cubic Spline
A flexible function of piecewise cubic segments joined smoothly at knots, constrained to behave linearly beyond the outermost knots.
Restricted Cubic Splines
A collection of piecewise cubic functions joined at knots and constrained to extend linearly beyond the data range, used to model non-linear hazard shapes.

S

Spline Model
A model using piecewise polynomial functions joined smoothly at knots to represent a flexible, non-linear relationship such as time and hazard.