Plans for analysis, definitions of stressors and outcomes, as laid out in this protocol, were determined a priori by our study leadership team in consultation with contributing study investigators, who provided input via conference calls and email. Individual study analyses will be performed by the investigators who collected the data, using standardized analysis scripts developed by the coordinating team at Washington University to implement a consistent analytical approach across sites. Results from these analyses will be sent to the coordinating team for meta-analysis. The consortium as a group will review and interpret the results. We have previously developed and successfully implemented this collaborative meta-analysis approach to investigate the genetics of addiction [37-39].
