Feasibility of a survey panel of GPs based on NIVEL GP registration systems

Several societal and policy developments favor the setup of a GP panel to consult the opinions and behavior of GPs in the Netherlands.
What is the feasibility of setting up a GP panel for survey and poll purposes, based on NIVEL registration data?
A first survey/poll among a sample of GPs will be conducted in the autumn of 2012, recruiting potential member so a GP panel
Insight in the opinions of Dutch GPs, and the impact of policy rich scenarios on current and present day issues regarding primary care policy and practice.