Model Estimation
Clinically preventable burden and cost effectiveness were
estimated using an algebraic model as described elsewhere.6,8
The use of algebraic models rather than Markov models or
microsimulations allowed more study resources to be devoted
to producing consistent results across all services.
Methods for producing consistent estimates of cost effectiveness
across preventive services are outlined in a methods
article and a detailed technical report.6,8 These methods are
consistent with the ‘reference case’ of the Panel on Cost
Effectiveness in Health and Medicine (PCEHM).14 Keeping
with these standards, the analysis from the societal perspective
includes the value of patient time to obtain services and
excludes productivity gains. All costs and benefits were discounted
to their present value at the age of 18 using a 3%
discount rate. Medical costs were updated to year 2000 dollars
using the medical consumer price index (M-CPI), and all
other costs were updated using the CPI for all items.