Comparison of the effects of cognitive-behavioral therapy for insomnia between patients with primary insomnia and comorbid insomnia. - Iwashita, Masayuki; Yamadera, Wataru; Hotchi, Ayana; Utsumi, Tomohiro; Amagai, Misato; Ishii, Junpei; Suzuki, Takako; Itoh, Hiroshi; Shigeta, Masahiro (Sleep & Biological Rhythms, 2022)