Unfortunately, we do not yet have research regarding how well writing CBM can be used
to actually monitor student progress or inform teaching practice. For instance, writing CBM may
lack face validity for teachers because writing is a complex generative activity that does not
easily conform to fixed preconceptions of typical or desired performance—one student maywrite a lengthy paper without errors and yet express weak, empty ideas without a driving purpose
while another may write much less with some mistakes but communicate to his or her audience
in a powerful way. Thus, it may be difficult to convince teachers that CBM will provide them
with useful data about their students’ writing to guide their instructional efforts. If, however,
CBM is viewed as one tool within a comprehensive assessment system, its potential might be
realized. Just as a good physician will not make a medical diagnosis based solely upon a general
outcome measure such as pulse, body temperature, or blood pressure, a good teacher will not rely
on a single type of measure or procedure to judge the writing performance of students.