The Dynamic Data Pull (DDP) is a special feature for importing data into REDCap from an external source system. It provides an adjudication process whereby REDCap users can approve all incoming data from the source system before it is officially saved in their REDCap project. The DDP can only be enabled by a REDCap Administrator, so you should contact them if you wish to utilize the DDP for this project.

The DDP has the ability to fetch data from the external source system both manually in real time and automatically at a regular interval. The DDP can only import external data for records that already exist in the REDCap project, in which it assumes that a record identifier (e.g. medical record number) is stored within each REDCap record so that the DDP can connect the REDCap record to a record from the source system. Once REDCap has a record identifier value for a given record, it will then go and immediately retrieve the data from the source system in real time, and later it will also check the source system at regular intervals for any additional data.

After a REDCap administrator has enabled the DDP for your REDCap project, the adminstrator can then give any user in the project access to the DDP (assuming the user has been authorized to access source system data), in which the user can be given user privileges to perform the mapping/setup process and/or to adjudicate/import data from the source system. Only an administrator can grant individuals access to begin utilizing the DDP. After being granted access to the DDP, the user will then see the DDP step on the Project Setup page where they can navigate to the DDP mapping/setup page, which allows the user to map fields already created in their REDCap project to fields from the external source system. This mapping allows REDCap to know how where to put the data when importing it from the external system.

A user on the mapping/setup page can choose any available fields from the external source system to map to one of their REDCap project fields. (Note: This assumes that the user has already created their data collection instruments and fields in their project.) There are two types of fields that may be mapped: 1) one-time data fields, and 2) temporal data fields. One-time data fields are those where data will only be stored one time in the source system, such as demography data. Conversely, temporal data fields are those where data may be collected many times over a period of time (e.g., labs, vitals, any kind of longitudinal data). When mapping temporal fields, you must also specify a REDCap date/datetime field that will be used for determining the window of time in which it should look when fetching data from the source system. It will determine the window of time in conjunction with the day offset value defined on the mapping page. For example, if the value of the mapped REDCap date/datetime field is 2001-11-29 and the day offset is 1 day, it will query the source system and return only data saved for the field from 2001-11-28 until 2001-11-30. Any source data outside of that range will be ignored during the adjudication process. It is important to note that the source data for a temporal field will NOT be fetched from the external source system UNLESS its associated REDCap date/datetime field has a value. Once a value is entered for the associated date/datetime field, source data will then be fetched for that temporal field.

On the mapping/setup page, you may choose up to 5 source fields to be used as 'preview fields'. Preview fields are optional and are typically used to confirm that the record identifier (e.g. medical record number) that was entered is correct by displaying other contextual data from the source system. For example, if you have 'last name' and 'date of birth' as source fields, you may choose them to be preview fields in your project, and thus when a value is entered in REDCap as the record identifier, if will then fetch and display the last name and date of birth of the person to validate their identity. If preview fields are not utilized, it is possible that incorrect source data is imported. Thus preview fields are not required but are recommended for data quality purposes.

After the mapping process has been completed, data from the external source system will not be imported automatically into the REDCap project, but instead it requires that a person view and adjudicate each data item from the source system before being imported into the project. The adjudication screen can be accessed from either of two places: 1) on the Record Status Dashboard, and 2) on the data entry form when viewing a record. The Record Status Dashboard will display a new table column with a count of any new items from the source system for each record displayed. Clicking on the count will open the adjudication screen for that record. Alternatively, when viewing a record on a data entry form, the count of new items from the source system will be displayed at the top of the page in red box, in which clicking the View button will open the adjudication screen. On the adjudication screen, it will display all data from the source system that has not been adjudicated yet. If only a single source value has been returned for a REDCap field, it will automatically pre-select that item for you. If the field is a temporal data field that has multiple values returned, it will automatically pre-select the data value *ONLY IF* that value is the only value returned that occurs on the exact same calendar date as the REDCap date/datetime value (that is, unless a pre-selection option - e.g., Minimum value, Latest value - has already been set for that field on the mapping page). The user must view all the items on the adjudication screen and select the radio button next to each to denote the source value they wish to import. Once all values have been selected, clicking the Save button will import the value into the project. If some items were left and were not adjudicated, the user can return at any time to adjudicate them in the future.