Contributor 1	Contributor 2	Contributor 3	Contributor 4	Contributor 5
Concepts	√	√	√		√
Design	√	√	√		√
Definition of intellectual content	√	√	√		√
Literature search	√	√	√	√	√
Data acquisition	√	√	√	√
Data analysis	√	√		√
Statistical analysis	√	√	√	√
Manuscript preparation	√	√			√
Manuscript editing	√	√		√	√
Manuscript review	√	√	√	√	√