The recordings were coded by the assistance researcher.
Then, the recordings were studied and calculated individually
by the researchers. The F/R ratio was determined by
measuring the time for a contraction to return to its baseline
from its peak and the time for a contraction to rise to its peak.
The F /Rs were averaged over the number of contractions.
The data were collected, and statistical analysis was
performed using SPSS 11.5 (SPSS Inc., Chicago, IL, USA)
software and chi–square test, correlations and ANOVA tests.