In recent years there has been a growing acceptance that to accurately assess the results of trials and other clinical research, and in particular to combine the results from different trials in meta-analyses, it is necessary to have access to the original source data, the “individual participant data” (IPD), as well as the result summaries found in published papers.
In addition, to make sure that the IPD can be fully understood and properly analysed, a variety of other study documents (protocols, analysis plans, etc.) are required. As a result, under pressure from funders and journal editors, more and more researchers are making such material (generically, “clinical trial data objects”) available for sharing with others. The datasets are rarely freely available - instead a variety of access mechanisms (e.g. individual request and review, membership of pre-authorised groups, or web based self-attestation), are used in combination with different access types (e.g. download versus in-situ perusal). Furthermore the various data objects are stored in a wide variety of different locations: a rapidly growing number of general and specialised data repositories, trial registries, publications, the original researchers’ institutions, etc.
The researcher or reviewer wishing to locate relevant data objects for a study is therefore faced with a bewildering mosaic of possible source locations and access mechanisms, and this problem of ‘discoverability’ will almost certainly become much worse in the future as more and more materials are made available for sharing.
Aims of the Project
The principal aim of the project is to combat this discoverability problem, by making the data objects generated from clinical research easier to locate, and by describing how each of those data objects can be accessed, providing direct links to them where that is possible. The central idea is to develop systems that can collect the metadata about the data objects, including object provenance, location and access details, and aggregate it into a single MetaData Repository (or MDR). The MDR is therefore designed to assemble, standardise and display the metadata about clinical studies and the data objects generated by them, and provide access to that metadata through a single system, accessed via a web portal.
The MDR system has been designed and developed by ECRIN (the European Clinical Research Infrastructure Network), in collaboration with (ONEDATA ) and INFN (Istituto Nazionale di Fisica Nucleare) at Bologna. Development of the whole project has been within the H2020 eXtreme - DataCloud(XDC) project, funded by the EU under grant agreement 777367.
Metadata from a variety of data sources have been collected by ECRIN using different modalities (e.g. DB download, import of XML files through an API, scraping of web pages) and stored in a relational DB on the test bed server at INFN. Data is then exported as json file metadata to the OneData file management system and indexed via Elastic Search to make it available to the web portal.
For further details about these processes please see the Methodology and Individual data source sections.