  Previous work has demonstrated the feasibility and value of conducting
distributed regression analysis (DRA), a privacy-protecting analytic method
that performs multivariable-adjusted regression analysis with only
summary-level information from participating sites. To our knowledge, there are
no DRA applications in SAS, the statistical software used by several large
national distributed data networks (DDNs), including the Sentinel System and
PCORnet. SAS/IML is available to perform the required matrix computations for
DRA in the SAS system. However, not all data partners in these large DDNs have
access to SAS/IML, which is licensed separately. In this second article of a
two-paper series, we describe a DRA application developed using Base SAS and
SAS/STAT modules for distributed Cox proportional hazards regression within
horizontally partitioned DDNs and its successful tests.
