What Constitutes Positive Mental Health in Young People? Examining Four Multi-Dimensional Models of Flourishing in 16 to 24 Year Olds

Traditionally, mental health issues have been managed using a disease deficit model of human functioning. The dominant focus has been on “what is going wrong?” rather than “what is going right?” Over the past two decades, researchers and clinicians have shifted towards addressing mental health from a positive perspective. This entails an increased focus on developing optimal functioning, enhancing strengths and facilitating healthy processes. A key aim of positive psychological practice is to teach people to flourish. Despite its significance, a universal definition and methodology for measuring flourishing is yet to be established. This is fundamental if positive psychology is to be formally recognised as a valid and reliable field. Moreover, establishing a universal definition and methodology has important implications for positive mental health research and practice; in particular, for young people who globally present with the highest rates of mental health issues compared to any other age group. To address this issue, this thesis built on previous literature that explored four multi-dimensional proposed models of flourishing in adults: the Mental Health Continuum (Keyes, 2002); the DSM-IV and International Classification of Diseases (ICD-10) definition of flourishing (Huppert & So, 2009); The Flourishing Scale (Diener et al., 2010) and the Positive Emotion, Engagement, Relationships, Meaning and Accomplishment (PERMA) Model (Seligman, 2011). The thesis focused on older adolescents, applying the responses of 2245 International Wellbeing Study participants aged 16 to 24 to dimensions proposed by the four models. It was found that Keyes’ 2002 Mental Health Continuum Model best measured flourishing in the respondents, supporting this model’s use with adolescents. The results also suggested that flourishing should be considered an age-specific dimension across the lifespan. Future research in this area should focus on young people and the eight constructs exclusive to the Keyes model that relate to social wellbeing and functioning in public life.