Add configurable minimum gap for MIMIC4 readmission

[thebean27]

Summary

This PR adds an optional min_gap parameter to ReadmissionPredictionMIMIC4.

Very short intervals between discharge and the next admission may represent internal transfers rather than true readmissions. With min_gap, users can define a minimum interval that must pass before a subsequent admission is labeled as a readmission.

• min_gap=None preserves the existing behavior.
• Existing positional arguments remain backward compatible.
• Added tests for the new behavior and backward compatibility.
• Updated the documentation and MIMIC-IV readmission example.

Testing

python -m unittest discover -s tests/core -p 'test_mimic4_readmission_prediction.py' -v

All 10 tests pass.

Also checked:

git diff --check

with no errors.

Fixes #1269

[thebean27]

@JosephSBoyle Thanks again, the PR is up. I’d appreciate your thoughts on the proposed min_gap logic.

[JosephSBoyle]

@thebean27 Thank you for this PR I had some suggestions for the prose but other than that it looks good.

One other thing I might suggest would be standardising the docs and examples to use a fixed period, either 3hrs or 1 day seem like reasonable candidates to my mind. If people default to the same thing this could help reproducibility. :)

Cheers,
Joe

[JosephSBoyle]

Looks fine to me, thanks @thebean27

@jhnwu3, I wonder if there should be a MIMIC-3 equivalent of this PR.
In any case I look forwards to this patch landing.

Best
Joe