How it compares

This page is an honest positioning of the builder against other FHIR Questionnaire / SDC tools — written to set expectations, not to market.

What this tool is

A zero-backend, single-page browser app served as static files. It combines a visual questionnaire builder with a live SDC runtime (FHIRPath, enableWhen, calculations, a real QuestionnaireResponse), plus import/export, extraction, translation and REDCap conversion — all in the browser, with no install and no server required.

Fair comparisons

The apples-to-apples peers are other browser-based questionnaire authoring tools with a renderer, such as NLM's LHC-Forms Form Builder and CSIRO's Smart Forms.

Full healthcare platforms — Aidbox, Medplum, the Firely ecosystem — are a different category. They bring a FHIR store, authentication and server-side operations. This tool deliberately does not compete on that axis: there is no backend to compare. When those platforms come up, only their authoring/runtime slice is a meaningful comparison.

Where it's strong

Nothing to install or host — open a URL and build.
The preview is a genuine SDC runtime, so logic behaves like a real client.
Broad FHIR R4/R4B/R5 + SDC support with faithful round-tripping.
Extras that many builders lack: Observation, definition-based and StructureMap-based extraction, machine translation, and REDCap ↔ FHIR conversion.

Where it's not the right tool

It is not a platform: no built-in FHIR server, no multi-user backend, no server-side storage beyond optional personal cloud save.
Some server-dependent SDC operations (like $populate) require you to point it at an external server.
StructureMap-based population (pre-filling a response) is not executed in the browser yet — extraction is; see Roadmap & limitations.

If you need a hosted, multi-user clinical data platform, use one of the platforms above. If you need to author, test and round-trip FHIR questionnaires quickly in a browser, this tool is built for exactly that.

Next: Roadmap & limitations.