Figure 1.

Assessment and diagnosis procedures in the control group* See the attached file Figure 1 and Figure 2. *Use of diagnostic tests (%) is calculated with respect to the number of attendances **Categorisation into the low or high risk group (i.e. completing an assessment according to the protocol) is defined as answeringall six questions concerning physiological parameters and medical history that are recorded on the specially designed assessment card, which also contained a request form for imaging or D – dimer, if applicable according to the rules of the structured decision tool [19]. The protocol-specific assessment did not occur for any of the control subjects and thus the risk profile for the control population is unknown.