When the host is known this approach quickly focuses the diagnosis to only a few possiblities.
Final identification is done by comparing images of the remaining possibilities.
The chart shown here is an example of how parasite stages might be grouped. Such a grouping can or should be taylored to the preferences of the examiner. Trophozoites are usually found in diarrheic and mucoid fecal samples. This is the most common for to find in feces and is most easily found in a thin saline smear. Feces will be formed.