Methods and devices are provided for diagnosing performance of a gastric restriction system. In general, the methods and devices can enable patients, health care providers, and others to use pressure data as a feedback mechanism to monitor efficacy of an implantable restriction device and to identify, train, and/or prescribe treatment plan options. Pressure data monitoring can be used locally and/or remotely to monitor a restriction in a patient and compare gathered pressure data with a typical pressure of the restriction. Based on the results of the comparison, possible problems related to the patient and the restriction can be identified and diagnosed with possible cause(s) and solution(s). Notice of any detected possible problems, causes, and/or solutions can be provided to a user.