This paper presents a model for an electronic medical record which sat
isfies the requirements for a faithful and structured record of patien
t care set out in a previous paper in this series. The model underlies
the PEN & PAD clinical workstation, and it provides for a permanent,
completely attributable record of patient care and the process of medi
cal decision making. The model separates the record into two levels: d
irect observations of the patient and meta-statements about the use of
observations in decision making and the clinical dialogue. The model
is presented in terms of ''descriptions'' formulated in the Structured
Meta Knowledge (SMK) formalism, but many of its features are more gen
eral than the specific implementation. The use of electronic medical r
ecords based on the model for decision support and the analysis of agg
regated data are discussed along with potential use of the model in di
stributed information systems.