Using an instrument such as the Clinical Microsystem Assessment Tool (CMAT) to examine microsystem performance can provide valuable guidance for the development of quality and safety initiatives within the microsystem. However, instruments developed for this purpose must take into account diverse literacy levels. Perceptions of health care professionals of the usefulness and readability of the CMAT were examined. Readability was determined with the Flesch Reading Ease scale, in which the CMAT was rated as "very difficult" to read, and a Simple Measure of Gobbledygook analysis revealed that 14.71 years of education would be needed to understand the content. Although the majority of the participating health care professionals identified the tool as useful, the high level of reading ability required to understand the content may create limitations for use, given the educational diversity of the health care workforce. Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.