Abstract: Immunoassay tests or agglutination tests run on samples of bodily fluid to detect the presence of particular compounds such as drugs in the body may be screened in the screening device. A test membrane is inserted into the screening device and illuminated. The reflected image is detected and the digitised data processed. For immunoassay tests, the digitised data is segmented and data for the test region is compared to that from the control region and the background regions to determine whether the test data exhibits any significant results. For agglutination tests, the digitised data is processed to determine the number and size of the areas of coagulation to determine whether the test data exhibits any significant results. A swab for taking a bodily sample incorporates a run fluid capsule.