This forest plot visualizes odds ratios with confidence intervals, displaying effect sizes from PCSK9 data across categorical groups including quartiles and a reference category. The React-based example uses D3 v6’s `scaleLinear`, `axisBottom`, and selection methods to render SVG elements. Each row shows a marker square positioned by the effect value, with horizontal lines spanning confidence bounds, and a reference line. The code computes the scale from data extents and supports SD-based intervals.