OBJECTIVE We investigated the effects of mindfulness-based cognitive therapy on insomnia (MBCT-I) in breast cancer survivors. METHODS In total, 136 participants were allocated randomly to a MBCT-I group or a waitlist control (WLC) group. Indicators of insomnia and mindfulness were evaluated using the Insomnia Severity Index, actigraphy and the Five Facet Mindfulness Questionnaire. Data were...