1.16 Tree Aggregation

If a signal identification analysis was requested in the Query Request Package (QRP) using the qrp.TreeFile input file, users can output aggregated analytic datasets in the QRP Reporting Tool that can be used as inputs to TreeScan™ software. Signal identification is available for Exposures and Follow-up Time (Type 2) and Medical Product Use in Pregnancy (Type 4) inferential analyses, as well as Self-Controlled Risk Interval (Type 3) analyses.

1.16.1 Output

Using the appropriate parameters in Create Report File, users can choose to output the signal identification analytic datasets alone or to additionally output a full report for Exposures with Follow-Up Time or Medical Product Use in Pregnancy inferential study designs. The full report will not include any information on the event of interest (including effect estimate tables, Kaplan-Meier curves, and forest plots) to maintain analytical integrity. For more information on these additional reports, see their corresponding sections in this documentation.

In the Tree Aggregation File, users can specify the analysis groups for which to output datasets as well as which data stratifications to output. Stratifications requested in the QRP Reporting Tool must have previously been requested in the QRP using the qrp.UserStrataFile. For Type 2 and Type 4 inferential analyses, users can request stratifications on the following factors: year, sex, age group, race, Hispanic ethnicity, month, geographic region variables, user-defined characteristic, as well as various combinations of the above factors. For Type 3 analyses, users can additionally request stratification based on time to censor and time to event.

For Type 3 analyses, users can optionally define fixed risk- and control windows in order to perform a Bernoulli TreeScan analysis, as opposed to a Tree-Temporal analysis. For more information on TreeScan™ and to download the software, see treescan.org.