What happened?
The models seem to have this test results range from 150 to 520; see this study for typical values: https://pmc.ncbi.nlm.nih.gov/articles/PMC2843567/, which seem to average around 17.
I personally have had lots of CBCs done, and I never had a PDW. I looked to see if a typical CBC in the US has a PDW; neither LabCorp not Quest offers it as part of a standard CBC (https://testdirectory.questdiagnostics.com/test/test-detail/6399/cbc-includes-differential-and-platelets?q=cbc&cc=MASTER, https://www.labcorp.com/tests/028142/complete-blood-count-cbc-without-differential).
I suggest removing it completely from the CBC definition from Synthea rather than try to correct its range.
Environment
Relevant log output