Differential costs for the non-adult ADHD population in Catalonia

Table 4 Differential annual costs accounting for adherence and total costs except costs related to ADHD drugs

	Two-part IV estimation
ADHD condition	285.84 (58.74)^c
Adherence (MPR)	785.67 (323.44)^b
ADHD condition	296.58 (54.08)^c
Adherence (PDC)	804.69 (323.88)^b
ADHD condition	404.86 (26.18)^c
Dummy full adherence (either MPR or PDC)	829.64 (332.42)^b

^a, ^b and ^c denote statistical significance levels 10%, 5% and 1%, respectively. Standard errors are in parenthesis. The sample size is 81,770 which refers to those fully adherent to medication. All regressions include as controls: the quarter of birth, age, gender, nationality, and the considered comorbidities (overweight, learning disability, depression, asthma, anxiety, conduct disorder, and defiant disorder), copayment levels plus pharmacy limits and basic health areas fixed effects