Key points are not available for this paper at this time.
Deon Filmer, Lant H. Pritchett, Estimating Wealth Effects without Expenditure Data-or Tears: An Application to Educational Enrollments in States of India, Demography, Vol. 38, No. 1 (Feb., 2001), pp. 115-132
Filmer et al. (2001) studied this question.