Patients presenting to emergency departments (ED) with non-specific complaints (NSC) such as "not feeling well", "feeling weak", "being tired", "general deterioration" are a very common and well-known, but poorly studied patient group. The differential diagnosis of NSC is extremely broad ranging from insufficient home care to acute life-threatening conditions. Therefore, the evaluation and diagnostic work-up of these mostly elderly patients with NSC is very time-consuming and not straight-forward. Furthermore, the assessment is complicated by comorbidities, polypharmacy or an altered mental status. For this reason, potentially unnecessary diagnostic efforts are undertaken in order to exclude a serious underlying condition, leading to prolonged throughput times and ED observation unit stays.

On the other hand, the patients' condition might be underestimated by ED physicians, which may result in ineffective, delayed or inadequate disposition, as well as poor patient outcomes. BANC (formerly BAUCAS) is a series of clinical studies with the intention to investigate the usefulness of clinical findings and biomarker levels combined for disposition of patients with non-specific complaints presenting to the emergency department.

Inclusion Criteria:

• All adult non-trauma patients with an Emergency Severity Index (ESI) of 2 or 3 are screened for inclusion

Exclusion Criteria:

• patients with specific chief complaints are excluded. Moreover, patients in whom an unambiguous and clear working hypothesis with logical management steps can be established are excluded

The protocol of the BANC study specifies that patients are consecutively enrolled in order to obtain a random sample of the source population of ED self-referred and referred patients with UC