Clear Writing: Ten Principles of Clear Statement

If you want to test the clearness of your writing, you may wish to consider using a 'fog index.' Fog indexes measure the complexity of writing samples, and often provide a means of calculating the reading or educational level required to understand a particular passage. Some fog indexes are available as computer software programs, or you may do the calculations yourself.

University of Missouri (1973). Articles>Writing>Rhetoric>Minimalism