Meta-analyses have demonstrated that mindfulness-based programmes are more effective than no treatment across different populations and desired outcomes yet there is limited evidence on how to sustain these benefits beyond the traditional eight-week courses. The 'Taking it Further' (TiF) programme was developed by the University of Oxford Mindfulness Centre to help reinforce and deepen one's mindfulness practice to promote well-being and mental health for life. The proposed study aims to evaluate the effectiveness of this programme in graduates of MBCT/MBSR on well-being and mental health outcomes and explore the mediators (i.e. mindfulness, decentring, and self-compassion) through which this programme has an effect over the course of twelve weeks using a randomised controlled trial with a waitlist control. The planned research is part of an overall effort to optimize treatment effects and the long-term effectiveness of mindfulness-based programmes.

Participants that expressed an interest in taking part in the study were screened for research inclusion/exclusion criteria and for course suitability. Research inclusion/exclusion was assessed by the lead researcher whereas course suitability was assessed jointly by the lead researcher and a trained mindfulness teacher at the Oxford Mindfulness Centre (OMC). Eligible participants were invited to complete baseline measures that assessed the primary outcome and mediator (well-being and mindfulness respectively) around two weeks before the start date and then again around one week before the start date to establish a stable baseline. For one of these online questionnaires, participants were instructed to complete an online orientation video to ensure continued eligibility. Within a few days of the start date, participants were randomised to the treatment (online TiF programme) or wait-list control group. One day before the start date, all participants were invited to complete a battery of questionnaires which assessed the outcome measures (well-being, psychological quality of life, depression, anxiety), mediator measures (mindfulness, self-compassion, decentring), and an additional measure regarding perceived expectations about the mindfulness course. Participants were then invited to complete a battery of questionnaires at weeks 4, 8, and 12 (post-intervention). For the battery of questionnaires for weeks 4 and 8, participants completed the same measures assessed at baseline with additional questions that assessed: the amount of practice, quality of practice, side effects of practice, and overall experience. For week 12 (post-intervention), participants completed the same measures as weeks 4 and 8 with additional questions that assessed the perceived credibility of the mindfulness programme, perceived quality of mindfulness teaching, and potential harm. Data collection was divided into two phases, with the first phase running from June-September and the second phase running from October-December 2021. The TiF courses were run online and the surveys themselves were also administered online.

Inclusion Criteria:

• English-speaking
• Has access to computer for online mindfulness sessions and assessments
• Participants who have completed an MBSR and/or MBCT course in the past

Exclusion Criteria:

• Has taken TiF programme prior to the start of the study
• Has completed a mindfulness programme that does not fit within the parameters of a formal mindfulness-based programme.
• Those that have recently experienced a traumatic event or bereavement and/or has been abusing substances to manage stress and/or has been harming themselves recently
• Participants on mindfulness teacher training pathway

The experimenter was unaware of who was allocated to the treatment or control group during data collection and analysis. A researcher external to data collection and analysis was in charge of randomization.