What functions does a data inventory serve?

The first step of data preparation is to create a data inventory of all items that have been received, including a list of specific items, sources, and dates requested/received. This inventory serves many functions:
1 ) A data inventory can be compared against the data request to determine which requested items are still outstanding.
2 ) Maintaining an inventory allows the analyst to note any gaps in the data, which may indicate missing records.
3 ) The data inventory enhances the efficiency of the analysis process by allowing the analyst to determine which tools or methods can be applied now and which must be delayed until additional data are received. Based on this information, the analyst can refine the data analysis plan to include a specific sequence of tests and an estimated time of completion for each. In addition to the functions noted previously, which provide value early in the analysis, the data inventory continues to serve a purpose throughout the entire engagement.
4 ) Data inventory is continuously updated as new data are received, acting as a progress meter for the data collection process.
5 ) When data (especially documents) are provided on a piecemeal basis or in no apparent order, organizing them can be a monumental effort before the actual analysis even begins. A data inventory can assist in this effort by facilitating a logical organization scheme.
6 ) The inventory is used at the conclusion of the engagement, when the report is being prepared. Many reports include a list of items reviewed and/or analyzed as an exhibit or appendix.

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