  The rarity and deeply embedded nature of stars with masses larger than 8
solar masses has limited our understanding of their formation. Previous work
has shown that complementing spectral energy distributions with interferometric
and imaging data can probe the circumstellar environments of massive young
stellar objects (MYSOs) well. However, complex studies of single objects often
use different approaches in their analysis. Therefore the results of these
studies cannot be directly compared. This work aims to obtain the physical
characteristics of a sample of MYSOs at ~0.01" scales, at 0.1" scales, and as a
whole, which enables us to compare the characteristics of the sources. We apply
the same multi-scale method and analysis to a sample of MYSOs. High-resolution
interferometric data, near-diffraction-limited imaging data, and a
multi-wavelength spectral energy distribution are combined. By fitting
simulated observables derived from 2.5D radiative transfer models of
disk-outflow-envelope systems to our observations, the properties of the MYSOs
are constrained. We find that the observables of all the MYSOs can be
reproduced by models with disk-outflow-envelope geometries, analogous to the
Class I geometry associated with low-mass protostars. The characteristics of
the envelopes and the cavities within them are very similar across our sample.
On the other hand, the disks seem to differ between the objects, in particular
with regards to what we interpret as evidence of complex structures and inner
holes. This is comparable to the morphologies observed for low-mass young
stellar objects. A strong correlation is found between the luminosity of the
central MYSO and the size of the transition disk-like inner hole for the MYSOs,
implying that photoevaporation or the presence of binary companions may be the
cause.
