## 3 Results
### Export of Data in ODM Format  
Direct allows the export of modelled data dictionary items through the ODM format into REDCap, as shown in Figure 9 below, and as such promotes interoperability of data though ensuring consistent eCRF design between trial sites. However, after the export of the modelled data dictionary items in ODM format into REDCap, some parts of the data dictionary items were found to be missing due to the inability of the format to allow parts of the modelled item that did not conform to CDISC standards to be exported. Such parts included the conformance and the cardinality of the modelled dictionary items. Hence, some data dictionary items which cannot be standardised in the CDISC format cannot be exported to REDCap. Furthermore, none of the modelled data dictionary items were able to be exported to Castor--another eCRF implementation--using the ODM format, as Castor at the time did not support the ODM. However, c4c has made significant progress through advocacy and collaboration with partners to influence the launch of a new update of Castor that will enable the exportation of the ODM format of modelled data dictionary  
Figure 7: Image of the HTML version of the modelled data dictionary. SDTM—Study Data Tabulation Model; FHIR—Fast Healthcare Interoperability Resources; CDASH—Clinical Data Acquisition Standards Harmonisation; HTML—hypertext markup language.  
items. There was also an issue with spaces in field names when the models were exported to REDCap. Direcht fields do not allow spaces (for, e.g., DateOfBirth), which means there were no spaces in these fields on the CRF. This was because element names in Direcht become variable names in the back end of the tool. It would be beneficial to have more than one EDC to test the ODM import, as this would help to determine what was tool specific and what needs to be changed at the ODM or data modelling layer. There was also a limitation on the transfer of code lists in the ODM format, and they had to be put into the free text node.  
Figure 8: Image of the mind map of a modelled data dictionary. EN—entry; CL—cluster; EL—element.  
Figure 9: Schematic diagram of the role of a modelling tool in a clinical trial environment.  
The team modelled the concept 'PregnancyRelatedProcedures' within Direcht and imported the ODM XML file into REDCap. REDCap was chosen as it is one of the more commonly used eCRF tools across the c4c consortium sites and claims to conform to the CDISC ODM standard [25]. It was therefore regarded as a suitable choice of eCRF to validate the Direcht ODM export. Overall, this export validation was successful; however, certain issues were identified:  
* The structure of the data model created two CRFs within REDCap, rather than one;
* REDCap took the first variable in the XML file as the Subject ID; however, the model did not have a Subject ID, and as a result, the first field in the data model was not usable in the REDCap project;
* Data were entered into Direcht without spaces, for example, 'DateOfBirth'. This format was exported into REDCap, affecting the user experience.  
These results have prompted discussions between the c4c team, Direcht, and CDISC to determine at which point in the process they occur and how to address them. This work is ongoing and will influence the next stage of the pilot.