A diagnostic device 1 for performing an immunochromatographic analysis of
a sample is disclosed. The diagnostic device 1 comprises a porous
substrate 10 for performing the analysis and a pre-filter 30 to remove
solid components, such as solublised faeces or samples containing
suspended organic material to prevent blocking of the porous substrate or
coloured particles so that the test result is more clearly visible. The
diagnostic device may include a container into which a sample may be
provided, with the interior of the container being sealably connectable
to the diagnostic section of the device. The porous section may be
encapsulated within a housing.