  Expressions for the Wick contractions contributing to the scalar pion
form-factor were computed model-independently in chiral perturbation theory at
next-to-leading order. The results reveal correlations amongst the different
contractions in terms of low-energy constants and allow for extrapolating
lattice data for individual Wick contractions. The quark disconnected
contribution to the real part of the form factor turns out to be suppressed
with respect to the quark connected one. The corresponding contribution to the
scalar radius has the same size as the connected contribution and can therefore
not be neglected.
