Despite the enormous popularity of co-teaching, there is
surprisingly little literature on the effectiveness of this
approach. In examining meta-analyses on the effectiveness
of a co-teaching model in an inclusive setting, Murawski
and Swanson (2001) concluded that insufficient data prevented
a clear determination, as only 6 out of the 99 studies
reviewed met the meta-analysis selection criteria. The latter
demonstrated a moderately significant size effect (+0.40).
The authors thus called for more research with experimental
and control groups with a more defined characterisation of
the populations involved to better determine how
co-teaching differs from other practices or when no special
educational services are provided. In a literature review,
Magiera and Zigmond (2005) observed that between 1986
and 2003, only 13 studies on co-teaching addressed student
achievement. Seven of these studies showed significant
positive academic gains for students with disabilities.