Changing complex behaviours such as tax evasion often requires combining several behavioural insights. We developed a tailored compound intervention approach to increase employers’ payroll tax compliance in Estonia’s construction industry. First, we used anthropological methods to gain insights into the decision processes of employers and employees in the industry (Study 1, N=16). These insights were combined with behavioural decision-making principles to design an e-mail with the aim to strengthen perceived risks and weaken descriptive norms of non-compliance as well as to strengthen collaborative and weaken adversarial construal of tax authority. The intervention was tested using a three-armed (1:1:1) non-blinded randomised controlled trial (Study 2, N=4770) involving all employers whose declared wages were below 70% of the industry’s average. The intervention significantly increased declared payroll taxes by 5.1% to 6.1% over a 3-month follow-up period (γI=11.95,p= 0.0001; γE=15.38,p< 0.0001). These findings demonstrate the feasibility of the compound intervention approach.
Alcohol assessment and feedback by e-mail for university students: main findings from the AMADEUS-1 randomised controlled trial
