Another limitation is that the four-week pre- and
postintervention time periods may not be typical
“windows” into the course of the disease. Seasonal
differences in disease-related symptoms might be
another limiting factor. Data collection occurred
during all four seasons. That said, enrollment was
timed such that for a given child, both the pre- and
postintervention phases were likely to occur in the
same season; most occurred during the fall