About 'frequency'
How to comprehensive the word 'frequency' in the following sentence:
Perhaps for us today, two of the most significant aspects of most of these studies of genius are the frequency with which early encouragement and teaching by parents ad tutors had beneficial effects on the intellectual development of children but caused difficulties of adjustment later in their lives, and the frequency with which abilities...
What word could I use to replace it?

Question

Answer

Instead of "the frequency with which", you could use "how often".

i.e.: how often early encouragement... had beneficial effects.