Some months ago I read an MSc in Computer Science thesis that can be very useful for your purpose: [An Investigation of Team Effectiveness in Agile Software Development][1] by Lars Martin Riiser Haraldsen. Its main objective is to investigate:

> *How does the Scrum methodology facilitate team effectiveness and what are the advantages and disadvantages?*

The author defines **team effectiveness** as a:

> *[...] measure of a team working together in such a way that the core goals are accomplished within a certain time frame and the team members are satisfied.*

The model adopted is based on this [paper][2] written by Salas, Sims, and Burke. According to these authors, the core components of teamwork include: **team leadership**, **mutual performance monitoring**, **backup behavior**, **adaptability**, and **team orientation**. All of these areas are needed to achieve good team effectiveness, but their implementation can be different from project to project.

I suggest you to give a look at **Chapter 5** to see the author's findings in detail. From **Chapter 6**:

> *Overall, I have found that Scrum facilitates teamwork and will in most areas increase team effectiveness. [...] the studies also show that when using agile development, such as Scrum, and follow the guidelines correctly, teams are satisfied and productivity improves.*


  [1]: http://www.diva-portal.org/smash/get/diva2:566359/FULLTEXT01.pdf
  [2]: http://www.uio.no/studier/emner/matnat/ifi/INF5181/h14/artikler-teamarbeid/salas_etal_2005_is_there_a_big_five_in_teamwork---copy.pdf