This paper examines the asymmetric behaviour of health care expenditure and disposable income
in the 50 US states over the period 1966-2009 using nonparametric Triples test techniques. The
results suggest that for 23 US states, real per capita health expenditures are characterized by
asymmetric behaviour, while real per capita personal disposable income series exhibit
asymmetric behaviour in 7 US states. Therefore, the main findings question the adequacy of
linear models when modelling the behaviour of these two series.