Balancing harm prevention and liberty preservation when implementing financial risk assessments for gambling in the United Kingdom: Insights from open banking data

BACKGROUND AND AIMS: The United Kingdom (UK) and Dutch governments have recently implemented mandatory financial risk (affordability) assessments for online gambling as a harm prevention measure. Assessments should trigger at a level of gambling expenditure that strikes a balance between harm prevention (most at-risk consumers should surpass the threshold) and liberty preservation (most no-/lower-risk consumers should gamble below it), yet little empirical research exists to guide threshold setting. We aimed to demonstrate how research can inform the harm-prevention, liberty-preservation trade-off in this context and evaluate the UK's proposed implementation of financial risk assessments. DESIGN, SETTING AND PARTICIPANTS: We reanalysed a dataset that combines self-reported Problem Gambling Severity Index (PGSI) scores and open banking data from consumers who gamble (n = 424) to (1) simulate the impact of the UK's rolling 30-day £150 net-deposit (deposits minus withdrawals) threshold for financial risk assessments, and (2) identify optimal threshold values for these assessments under different circumstances. Participants were UK residents who had gambled in the past year, recruited via Prolific in April 2024. MEASUREMENTS: Participants completed a survey containing the PGSI and agreed to provide their past 12 months' banking records. FINDINGS: Over 12 months, two-thirds of at-risk (PGSI ≥1) and nearly half of no-/lower-risk participants crossed the UK's £150 threshold [area under the curve = 0.66, 95% confidence intervals (CIs) = 0.62-0.71], demonstrating a greater emphasis on harm prevention over liberty preservation. Increasing the value to £186.9 (95% CIs = £69.5-£401.7) slightly improved this balance, although £150 remained within the range of appropriate values. Optimising for harm prevention in our sample required lowering the threshold to £39.0 (95% CIs = £29.6-£58.8), while emphasising liberty preservation increased it to £716.5 (95% CIs = £508.5-£990.9). We found that using a more conservative definition of risk (≥2 PGSI harms) resulted in higher thresholds, and lower thresholds may be appropriate for younger adults (