Positron emission tomography (PET) is a nuclear medicine procedure that examines the metabolic activity of cells and tissues. A radioactive substance (tracer) is administered, which allows a computerised tomography (CT) or magnetic resonance imaging (MRI) scan to reveal the metabolic activity in the body on the basis of how the tracer is taken up by the body’s tissues. PET scans are mainly used to diagnose cancer. The Swiss Atlas of Healthcare comprises analyses on the overall frequency of PET scans and separate analyses for outpatient and inpatient settings. For the charging of PET scans in outpatient settings, either flat rates or TARMED equivalents can be used. If they are charged using TARMED equivalents, the frequency of PET scans cannot be determined from the invoicing data. This is why the frequency of outpatient PET scans and the total are only shown from 2019 onwards. Since 2019, flat rates have been used for billing in the large majority of cases.