Psychological distress (PD) is a major public health concern linked to progressive disability. Estimating PD transition probabilities is essential for guiding targeted interventions and policies, particularly in the context of health economic models used for pharmaceutical reimbursement. We aimed to quantify how transition probabilities vary by socioeconomic status across 4 health states of PD (no PD, mild PD, moderate PD, and severe PD) among Australian adults with PD.
We obtained data on PD status and socioeconomic characteristics from the Household, Income and Labour Dynamics in Australia survey (2007-2021). We used a 4-state continuous-time Markov model to describe annual transitions between PD states. The model allowed tracking of both forward and backward transitions, enabling movement between any pair of states, including persistence of the same state. Socioeconomic status was assessed using education, employment, and income.
Overall, 25 232 participants were identified for the study. The highest probabilities of worsening were for transitioning from mild PD to moderate PD (16.9%), whereas the highest probability of improvement was recorded for the transition from moderate to mild PD (32.3%). Higher recovery rates from severe PD to no PD were observed among individuals with higher education levels than in those with lower education (8.6% vs 5.8%), among the employed compared with the unemployed (7.0% vs 4.8%), and among those in the highest income bracket compared with those in the lowest (12.7% vs 5.7%).
The estimated transition probabilities can be used in health economic evaluations, designed to support reimbursement decision for interventions.