So let's look at how CBT-I works. Like we saw in medications, there have been three med analyses evaluating the effects of cognitive behavioral therapy for insomnia. Again, the left column shows a variety of subject of sleep parameters that are of importance when evaluating effects on insomnia. And again, the numbers in the table indicate effect sizes. That is the difference between the individual who's treated and an individual who's not treated in standard deviation units. You can see similar to medications looking at the table, the effects of cognitive behavioral therapy for insomnia on mostly parameters or in the moderate to large effect size range. One exception to this is on total sleep time where the effects generally are smaller. So what does that translate into in terms of minutes? This slide shows absolute changes in sleep parameters with cognitive behavioral therapy for insomnia derived from the meta analyses. So if we're talking about number of minutes and percent of improvement, if you look from pre-treatment to post-treatment, sleep latency or ability to fall asleep improved by roughly 50 percent. Same with wake after sleep onset. That is minutes awake in the middle of the night. Same with a number of times people estimate they wake up during the nighttime. But again, you can see there's a relatively small improvement in total sleep time at the end of most treatment trials which can last six to eight weeks. So if baseline on average individual started roughly estimating they sleep six hours a night and a post-treatment that only increases to about six and a half hours a night. But many of the other important sleep parameters improved by as much as 50 percent. There have been a few trials that have compared cognitive behavioral therapy for insomnia to common pharmaco or medication therapies within the same trial or head-to-head comparisons. This is one study published a few years ago that was conducted in 46 older adults who had chronic insomnia. And they were randomized to receive six weeks of either cognitive behavioral therapy for insomnia, medication Zopiclone, which is kind of a cousin medication to a Zopiclone, or a placebo medication. You can see that the graph represents total wait time. That is how long to fall asleep plus time awake in the middle of the night. And you could see that at post-treatment after six weeks, the group that was assigned to cognitive behavioral therapy for insomnia had less wait time relative to the placebo group as well as relative to the Zopoclone 7.5 milligram group. The two active treatments were then followed up six months post-treatment. And you can see in green, that's identified in green, you could see that the cognitive behavioral therapy for insomnia groups still had less wait time than the Zopiclone group, six months post-treatment. So in this particular case, at least the individuals with primary insomnia, it seems that in head-to-head comparisons, cognitive behavioral therapy for insomnia does better than at least this particular medication at post-treatment and the effects are sustained in cognitive behavioral therapy for insomnia and remain better than that medication group six months post-treatment. Similar to what we saw for the medication conditions, one of the increasing strengths of this line of research has been that we've taken and looked at the efficacy of cognitive behavioral therapy for insomnia not just in individuals who have primary insomnia, but also in individuals who have insomnia that's co-morbid with other disorders such as mental health disorders. And of all the co-morbidities, mental health disorders are most common co-morbidities that go along with insomnia. This was a small pilot study that looked at 30 patients who had both insomnia and depression. In this case, they received 12 weeks of mood medication escitalopram also known as Lexapro, and they had seven weeks of individual cognitive behavioral therapy for insomnia or an active behavioral placebo. This was a very rigorous trial that used an active behavioral placebo rather than a treatment as usual condition to really evaluate the effects of adding cognitive behavioral therapy for insomnia to a depression treatment regiment. The graph represents the percent of patients achieving remission to their insomnia on the left and to depression on the right. Taking insomnia first, you can see that the group that got the combination of Lexapro plus cognitive behavioral therapy for insomnia, were much more likely to achieve remission to their insomnia than the group that got escitalopram with the placebo. Similar results were found for depression so that almost twice the number of individuals who were in the combined escitalopram and cognitive behavioral therapy for insomnia group achieve remission compared to only about 33 percent a, standard measure that's found in many depression trials, among those who got escitalopram and placebo. However, this was not statistically significant perhaps due to low power because the sample size was relatively small. But this early part of study did lend support to the idea that in individuals who have both insomnia and depression, treating both things at the same time may help people achieve remission to both their insomnia as well as to their depression. These studies are being followed up in larger samples. One of the biggest advantages of cognitive behavioral therapy for insomnia is its long lasting effects. This is perhaps a seminal study that looked at the long-term efficacy of cognitive behavioral therapy for insomnia relative to medications. In this particular study, older individuals were assigned to receive other cognitive behavioral therapy for insomnia for eight weeks. A medication for insomnia for eight weeks for their combination. The treatments were then discontinued and people were followed up at various time points. Here you're looking at the two-year follow-up of individuals in the cognitive behavioral therapy for insomnia group and the medication group. On a number of different subject of sleep parameters including wakefulness during the night and total sleep time and sleep efficiency. The graph represents the percent change from pre-treatment for both the CBT-I condition, the cognitive behavioral therapy for insomnia group, as well as the medication group. And you can see that for the cognitive therapy for insomnia group at orange, they remained substantially improved in terms of their wakefulness during the night, total sleep time and sleep efficiency relative to baseline. Whereas the medication group had almost receded back to their baseline levels. So one of the greatest advantages of cognitive behavioral therapy for insomnia seems to be that treatment not only helps when people are doing it, but even when they stopped active treatment the effects of the treatment seemed to be long lasting for periods as long as two years.