Detection model in the model zoo, does not support datasets with no nodules

Hello
The Monai bundles are convenient to use because all the config for traning, transforms etc are specifyable easily as JSON and we are fortunate to have such a turnkey way of training the detection pipeline. The reference Lung Nodule detection, which is really the only detection in the model zoo, does not support datasets with no nodules, which would be a very odd thing to do in the medical field, because one would expect several healthy patients with no lung nodule. A medical detection network that is trained only on diseased samples is flawed right in its data input distribution. I am guessing that something like StandardizeEmptyBoxd needs to be added to the _transforms section of the lung_nodule_ct_detection/configs/train.json of the model zoo https://github.com/Project-MONAI/model-zoo/releases/download/hosting_storage_v1/lung_nodule_ct_detection_v0.5.9.zip. Any guidance would be appreciated.

Thanks
Rajesh

Start with lung_nodule_ct_detection/configs/train.json from the model-zoo archive and inspect the _transforms section, including the suggested StandardizeEmptyBoxd transform. Check how the detection training pipeline handles samples with no nodules; done means datasets containing healthy patients can train without failing or being treated as invalid.