[Peter]

Determining which stakeholder to involve is usually pegged on the time of the study,that is the study population,the location of the study and the resources available for stakeholder engagement.We usually tie the engagement to the best approach usually maximizing on the the available resources for maximum out put.We also use past experiences to determine which stakeholder is more practical to work with.I have previously seen some stakeholders decline participation despite making all efforts to involve them.Availability of resources and the inclusion of stakeholder involvement in the protocol determines  the extent and who to involve.