Abstract
This paper analyses the effect of unmet formal care needs on informal caregiving hours in Spain using the two waves of the Informal Support Survey (1994, 2004). Testing for double sample selection from formal care receipt and the emergence of unmet needs provides evidence that the omission of either one of these two variables would causes underestimation of the number of informal caregiving hours. After controlling for these two factors the number of hours of care increases with both the degree of dependency and unmet needs. In the presence of unmet needs, the number of informal caregiving hours increases when some formal care is received. This result refutes the substitution model and supports complementarity or task specificity between both types of care. For the same combination of formal care and unmet needs, informal caregiving hours increased between 1994 and 2004. Finally, in the model for 2004, the selection term associated with the unmet needs equation is larger than that of the formal care equation, suggesting that using the number of formal care recipients as an indicator of the goodness of the long-term care system may be confounding, if we do not complete this information with other quality indicators.