How to create lines of therapy charts

An intuitive way to visualize lines of therapy data is a Sankey diagram: it shows in one view how many patients stay on a therapy or switch to another from one line of treatment to the next.

Lines of therapy data can be difficult to communicate clearly.

You may have a table showing first-line, second-line, and third-line treatments, along with how many patients continue, switch or discontinue treatment at each step. But in table form, the main pathways are not always obvious.

A Sankey diagram is one practical way to make that pattern easier to see.

Instead of reading treatment transitions row by row, you can quickly identify the main therapy pathways, the largest branches, and where the flow becomes more fragmented over time.

This makes Sankey diagrams useful for lines of therapy charts, treatment pathway visualizations and other healthcare flow charts, because they show both sequence and volume in one view.

What data you need

In simple terms, a lines of therapy Sankey diagram only needs three columns:

• From: the start node of the flow this row defines
• To: the target node of the flow
• Amount: the number of patients, which sets the width of the flow

Each row represents one transition from one therapy to the next, along with the number of patients following that path. To make the data work correctly, the treatment name should always include the treatment stage, such as OXC (1L), OXC (2L), and OXC (3L), where 1L, 2L and 3L stand for first, second and third line of therapy.

This keeps the stages distinct in the chart, even when the same therapy appears in multiple lines of treatment.

The example follows patients on antiseizure medications, abbreviated the way epilepsy studies often do: OXC for oxcarbazepine, LEV for levetiracetam, VPA for valproate and so on.

Here is our example to get you started:

Fine-tuning the chart

Once the data is entered, SankeyArt automatically turns it into a Sankey diagram, like the one at the top of this post. From there, a few small adjustments can improve readability further:

• Apply colors to all chart nodes, keeping therapy colors consistent so recurring therapies remain easy to recognize across stages
• Adjust the layout manually where needed by dragging nodes to make the main treatment patterns easier to see

Beyond lines of therapy

The same approach also works well for other healthcare flow charts, including:

• patient journey diagrams
• referral pathways
• treatment switching patterns
• care pathway maps
• discharge pathways

Any time you need to show how patients, treatments or cases move through a sequence, a Sankey diagram can be a useful format.

Have a healthcare use case you would like to visualize? Write to us at support@sankeyart.com.