400
Analysis of epidemiology research on stuttering indicates that _________ is the variable that affects the true understanding of the prevalence and incidence of stuttering.
a. duration
b. the number of new cases
c. normal fluency development
d. child development
What is A. Duration
There is no universal measure by which parents and researchers define "duration" therefore, duration truly influences the interpretation of research data and information about the development of stuttering.