# Decision Language specification questions

**Category:** [Task Planning/GDL](https://discourse.openehr.org/c/task-planning-gdl/27)
**Created:** 2021-10-28 14:51 UTC
**Views:** 610
**Replies:** 2
**URL:** https://discourse.openehr.org/t/decision-language-specification-questions/2001

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## Post #1 by @Francini_Hak

Good afternoon.
I am reading the Decision Language specifications and I have a few questions.
Is the DLM model concrete package related to the subject proxy? If so, how are they related? Especially for tracked variables and quantitative variables, since the proxy service takes currency and quantity of variables into account.
Should variable calls be done in the input section or only in the data binding section? In case a DLM uses data binding to external sources (non-subject-oriented).
Thank you in advance.

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## Post #2 by @thomas.beale

First thing: the Decision Language is under development, so don't treat it as a) complete or b) correct. It's trying to be those things, but is almost certainly not there yet!

The [openEHR CDS, Guidelines and Planning Examples](https://specifications.openehr.org/releases/PROC/latest/process_examples.html#_multi_drug_chemotherapy) provides a fair few examples of DLMs, as currently conceived, which might help.

To understand the relationship of Subject Proxy with CPGs, DL etc, - see the [CDS, Guidelines and Planning Overview, particularly section 4](https://specifications.openehr.org/releases/PROC/latest/overview.html#_formalisation) and also section 6. Essentially the Subject Proxy service populates variables representing events and states from the external world (usually the patient), for a DLM and /or TP workflow to consume.

The 'input' and 'rules' sections of a DLM are not semantically important, they are more to make it easier to distinguish input variables from rules and other variables (if defined).

We're still working on details of both the Subject Proxy service and also things like tracked variables; both are likely to change due to more recent work not yet visible in the specs.

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## Post #3 by @Francini_Hak

Thank you for your fast answer! I will check those sections. Hope to see updates soon :)

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**Canonical:** https://discourse.openehr.org/t/decision-language-specification-questions/2001
**Original content:** https://discourse.openehr.org/t/decision-language-specification-questions/2001