Segmented Linear Regression Models for Assessing Change in Retrospective Studies in Healthcare

<div>30-day mortality versus time <i>t</i> in days from the start of the study. The vertical dashed line marks the onset of the HFU. The single line (black) is the best-fitting linear model for the entire period: equation <i>y</i> = −0.00002<i>t</i> + 0.0720. The dashed blue lines show plateaus are the best-fitting linear models for the pre-HFU (<i>y</i> = 0.0547) and post-HFU (<i>y</i> = 0.0314) periods. Data points 0 or 1 for dead or alive in red.</div>

Computational and Mathematical Methods in Medicine

fig4

Figure 4

Figure 4: Segmented Linear Regression Models for Assessing Change in Retrospective Studies in Healthcare 