We understand that is a concern for users. Unfortunately, no cell counting device is 100% accurate - nor is a user counting with a microscope and clicker. A sample will vary at different points of the slide in terms of cell density and therefore the results will also be different.
If accuracy is top priority - the user is advised to take counts at several positions of the slide and then average the results - as they would with a microscope. This will alleviate any over-under estimations.
The cell counter looks at the image in a 2D plane, mathematical calculations revolving around the depth of the slide are then added to account for the volume, this means that missing cells will be accounted for.
Lastly, due to differences in focal levels - not all cells in the sample will rest at the same level, this means that they will look different and be overlooked by the algorithm. This is accounted for by the calculation in the previous paragraph.
Users are always welcome to download their images and provide them to CytoSMART for review. We will do our best to help.