Methods of correcting double-differential slow-neutron scattering data for multiple scattering have been investigated and applied to three important experimental studies of room-temperature water. The corrections obtained are very significant, particularly for low-momentum transfer data, which in some cases require corrections of 50% or more. However, uncertainties are introduced into the correction process by sensitivity to theoretical models, which must be used to calculate the multiple scattering. The choice of the correction method and interpretation of the corrected results in the presence of these uncertainties is considered in detail.