A common reason for refusing to use a rapid test is that the test person finds it extremely uncomfortable or even painful to insert a swab into the nose to take a sample.
Although it is sometimes sufficient with modern rapid tests to take a nasal swab at a depth of only 1.5 cm, the initial rejection often remains or the sample collection is difficult due to anatomical conditions. Testing children in primary schools, for example, is also difficult because the children have to carry out the rapid tests themselves for legal reasons and teachers are allowed to assist, if at all.
Based on this problem, antigen tests were developed that do not require a nasopharyngeal swab at all. These rapid tests, colloquially known as spit tests, work with a saliva sample that is given directly into a saliva collection vessel and from there applied directly to a test cassette using a pipette. This test method thus offers the greatest possible convenience in that it is completely non-invasive, with just as high reliability in terms of sensitivity and specificity as standard nasal swab tests.