The use of flexible models for the relationship between a quantitative covariate and the response variable can be limited by the difficulty in interpreting the regression coefficients. In this article, we present a new postestimation command, xblc, that facilitates tabular and graphical presentation of these relationships. Cubic splines are given special emphasis. We illustrate the command through several worked examples using data from a large study of Swedish men on the relation between physical activity and the occurrence of lower urinary tract symptoms.
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