(An informal perspective)
Prelude: You are free to copy and distribute
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modification date: May 24, 2000.
Address any questions, comments, or suggestions to Mario
Introduction. Compensation is probably the
least understood process accompanying flow cytometric analyses.
Perhaps this is because it is often described with the linear
algebra elements needed for its computation, and many of us have
forgotten what linear algebra is, much less how to do it. However,
proper compensation is absolutely crucial for some aspects of
flow cytometry, one of which is antigen density measurements.
Unfortunately, because compensation is often misunderstood, and
because there is so much incorrect mythology about it floating
around, many laboratories do not set compensation properly.
In this "perspective," I will try to address the issues
surrounding compensation, attempt to dispel many of the myths,
and hope that by the end, that I have not confused anyone but
rather have convinced them what proper compensation is.
Please start with the quiz, and work through the perspective in
order suggested. The table of contents
below will allow you to go directly to any page.
Start with the Quiz!
If you are really adventurous, you can navigate through a more
detailed (and more rigorous) discussion of compensation, complete
with examples of the math, examples of the pitfalls of poor compensation,
etc. I recommend this only after you have finished with the more
informal, relaxed discussion... To start the detailed discussion,
Table of contents:
Introduction (top of this page)
Importance of compensation
Errors introduced by compensation
List of Figures:
Figure 1a (quiz,
Figure 1b (quiz, part
Figure 2: Compensation
& cell enumeration
Figure 3: Errors introduced
Figure 4: Practical compensation
Figure 5: Compensation
& sensitivity settings