XML4Pharma RESTful Web Services: Differences with the CDISC Library API RESTful web services
IMPORTANT: The content of this page is being updated regularly.
Many people within the CDISC community will wonder how our RESTful web services relate to the new CDISC Library API RESTful web services,
formerly known as "SHARE 2.0 API". There surely is some overlap. but also a number of differences. Some of all of this is explained below:
Strongly recommended: CDISC members can (and should) view the "CDISC Library Launch Webinar"
- First of all, we need to emphasize that our RESTful web services are NOT meant to compete with the RESTful web services provided by the CDISC Library.
At the contrary, we strongly recommend that members of the CDISC community move to the RESTful web services provided by the CDISC Library as soon as possible.
- Our own RESTful web services have been developed at a time that CDISC was only starting to think about providing CDISC standards in a machine-readable way.
Providing CDISC content in a machine-readable way is something we already strive for since many many years. It is however only in the last years that this idea has been picked up by CDISC.
Even then, there is still a lot of resistance within a number of the standards development teams, as these are used to provide new versions of the standards as PDF (or recently: HTML) documents,
with some of it available as an Excel worksheet in the best case.
- Our RESTful web services have primarily been developed to demonstrate the feasibility of providing CDISC standards content as "machine services" and
to provide functionality that can be used and consumed by software programs (like validation tools, mapping tools etc.), as a better alternative for manual lookups in PDF documents.
So if one day, hopefully in the not too far future, we can switch off our RESTful web services, as everyone is using the CDISC Library API RESTful web services,
we can only see this as a huge success.
- We have always closely worked together with the CDISC team that is developing the CDISC Libabry and its API. We had many very good discussions about how such
RESTful web services can and should work, and what kind of features and functionality can be provided. We see our own RESTful web services as early prototypes and
demo examples how such features can be provided
- As far as we can see at this moment (February 2019) there surely is some overlap in functionality and features with the CDISC Library API RESTful web services, but there are also some differences.
As the CDISC Library API evolves, one should be able to obtain all of the functionality that our services provide, by using the CDISC Libabry API, however in a somewhat different way.
This will be explained further on.
- An important difference is that the CDISC Library RESTful web services have been developed in a professional way. Our own RESTful web services never had this ambition.
This is also due that our own RESTful web services have been developed in our sparse free time (usually in weekends), and had no commercial goal (they are free). We just wanted
to demonstrate the CDISC community how such RESTful can help automating a lot of tasks that are otherwise done manually, so are time-intensive and error-prone.
- Our own RESTful web services are being used by many pharma companies, CROs and other service providers, also in a number of their products.
We do encourage these companies to gradually move these implementations to use the CDISC Library API RESTful web services.
As we are specialists in developing software for use with RESTful web services, we can help these companies in making this transition.
- An important difference is that our RESTful web services are more "bottom up", whereas the CDISC Library API RESTful web services are more "top down".
Both approaches are good ones, and one is not better than the other. Let me explain:
For example, if you (or better your software) needs to know whether an SDTM variable is "required", "expected" or "permissible" in the context of the given standard and the given IG version,
you may get a "direct" answer (i.e. "required", "expected" or "permissible") by using our "CDISCCoreFromSDTMVariable" RESTful web service.
In the case of using the CDISC Library API RESTful web services, you will query for the properties of the variable (given the IG version) and obtain ALL the properties as either (your choice)
as JSON, ODM-XML or RDF (in future). Your application will then need to look up the "core" property and retrieve it.
With the XML4Pharma approach you will only get the "core" property, and not all the properties of the given variable.
Another example is checking whether a certain value is a valid value in a given codelist and codelist version (there are sometimes major difference between codelist versions).
Using our service "ValidValueInCodeList" your application will get a direct answer (i.e. "true" or "false") whereas in the CDISC Library approach, your application will ask for all the terms in the codelist,
and then compare your value with those in the list obtained by the RESTful web service.
We selected our approach as we did not want to more or less "redistribute" the CDISC standards and contents, but wanted to provide low threshold methods answering direct questions.
You may also define our approach as "very pragmatic", whereas the CDISC approach is much more "systematic" (which is very good).
- Our own RESTful web services are free and can be used by any application without any authentication. The CDISC Library API RESTful web services will require
authentication, but will be free of charge for CDISC members (state: February 2019). Developers in member companies will be able to obtain credentials through their CDISC membership contact person (again, state: February 2019).
Some of our RESTful web services, such as our LOINC services
are not planned for in CDISC, and will remain fully operatable in the future. Other organizations are currently also developing RESTful web services for use with LOINC,
such as the LOINC FHIR Terminology Server, which (again) is an extremely welcome evolution.
- The code of our "UCUM" RESTful web services have been donated to the National Library of Medicine.
You can find there description here. We do continue working closely together with the NLM and with
the NLM and the Regenstrief organization to extend these services and to promote them for use in clinical research.
For example, automated conversion between "conventional" and "SI" units (these terms are however confusing) can only become possible through the use of
UCUM notation, which is unfortunately not allowed by CDISC yet.
- The RESTful web services supporting the "Open Rules for CDISC Standards" will remain available.
The new CDISC working group "Open Rules for CDISC Standards" just started its activities. The long term goal (under discussion) is to have the "Open Rules"
under the governance of CDISC, and to have them available as part of the CDISC Library, and possibly to provide RESTful web services for them.
A presentation about this will be given at the 2019 CDISC European Interchange in Amsterdam.
Courtesy of XML4Pharma - last update: February 2019