In the four larger trials expected to be published in 2014, researchers had participants keep sleep journals to track the effect of the CBT-I therapy, writing down what time they went to bed every night, what time they tried to fall asleep, how long it took, how many awakenings they had and what time they woke up.
From http://www.nytimes.com/2013/11/19/health/treating-insomnia-to-heal-depression.html?_r=0