Intervention efficacy among 'at risk' adolescents: A test of subjective wellbeing homeostasis theory

This study tests a number of theoretical predictions based on subjective wellbeing (SWB) Homeostasis Theory. This theory proposes that SWB is actively maintained and defended within a narrow, positive range of values around a 'set-point' for each person. Due to homeostatic control, it is predicted to be very difficult to substantially increase SWB in samples operating normally within their set-point-range. However, under conditions of homeostatic defeat, where SWB is lower than normal, successful interventions should be accompanied by a substantial increase as each person's SWB returns to lie within its normal range of values. This study tests these propositions using a sample of 4,243 participants in an Australian Federal Government Program for 'at-risk' adolescents. SWB was measured using the Personal Wellbeing Index and results are converted to a metric ranging from 0 to 100 points. The sample was divided into three sub-groups as 0-50, 51-69, and 70+ points. The theoretical prediction was confirmed. The largest post-intervention increase in SWB was in the 0-50 group and lowest in the 70+ group. However, a small increase in SWB was observed in the normal group, which was significant due to the large sample size. The implications of these findings for governments, schools and policy makers are discussed.