The planning phase of the project will focus on the development and refinement of the risk assessment and referral tool (PORRT). This will be accomplished through a systematic review of the literature to provide the scientific evidence for risk factors for ECC, and if sufficient information can be derived from the literature, we will develop a three-state (normal, non-cavitated and cavitated lesions) Markov-model to enable comparisons of ECC incidence rates among children with different risk factors.