| Studies | Division criteria | User roles | Methodology |
| | Participation | Idea generator Socializer Efficient contributor Master Passive commentator Passive idea generator | Social network analysis Clustering analysis |
| | Interactor information provider coordinator encourager | Improved PEP model | |
| | Peripheral user formal user core user | Social network analysis | |
| | Lurkers, Quiets, Coys, Stars, Movers, Shakers | Social network analysis Empirical analysis | |
| | Contribution | Peripheral participant active contributor core contributor | Empirical analysis |
| | Participation Contribution | Project leader Generalist Active designer Communicator Passive designer Observer | Social network analysis Clustering analysis |
| | Active login active participant indirect contributor direct contributor | Empirical analysis |