  Medical progress notes play a crucial role in documenting a patient's
hospital journey, including his or her condition, treatment plan, and any
updates for healthcare providers. Automatic summarisation of a patient's
problems in the form of a problem list can aid stakeholders in understanding a
patient's condition, reducing workload and cognitive bias. BioNLP 2023 Shared
Task 1A focuses on generating a list of diagnoses and problems from the
provider's progress notes during hospitalisation. In this paper, we introduce
our proposed approach to this task, which integrates two complementary
components. One component employs large language models (LLMs) for data
augmentation; the other is an abstractive summarisation LLM with a novel
pre-training objective for generating the patients' problems summarised as a
list. Our approach was ranked second among all submissions to the shared task.
The performance of our model on the development and test datasets shows that
our approach is more robust on unknown data, with an improvement of up to 3.1
points over the same size of the larger model.
