Lesson 9: Data Query in a Federated Environment
- Distributed query: securely obtaining useful data from diverse EHR systems and other sources.
- ONC supported Query Health initiative.
- Query Health initiative related video (The first 18 minutes is a good general introduction to distributed query that you should watch. The rest describes individual query reporting systems.)
Slides from the video
Article about Distributed data network
Desired attributes of Distributed data network
- Govern is more important
Secondary Use
Data from Multiple Institutions
why do we need distributed systems
Rationale 1
rationale 2
rationale 3
chanllenges 1
Challenges 2
hQuery
- hQuery's goal: simplicity. limited but well standardized data set (in quality measurement and other common clinical activities).
- point-and-click interface (called the hQuery composer) to non-technical healthcare providers.
- the possible queries are somewhat limited.
- hQuery uses a simple patient information model to facilitate query building by nontechnical users.
- hQuery Gateway
- located at source system
- receives queries in a standard format
- forwards queries to an adapter
- the adapter translates the query, receives response and converts it into the standard data model for transmission back.
- Video about hQuery.
- HQuery presents results in an attractive way (frequency, time and geographic distributions).
hQuery query composer
Patient information model
hQuery reports
Quiz 1
- the curly braces problem is a technical sub-issue of interoperability problem
Informatics for Integrating Biology and the Bedside (i2b2)
I2b2
- is NIH-funded effort based at Partners HealthCare System in Boston, Mass. * mission: enable clinical investigators to conduct research using genomics and biomedical informatics.
- is sophisticated to support complex research environments
- provides an easily understood database schema
i2b2 Hive and cells
- i2b2 “cells” communicate via web services and are together called a “hive”.
- Custom cells can be added to the hive.
- i2b2 users group (share information and applications; create the potential for translational research)
Quiz 2
- extracting clinical concepts or features from free text format clinical notes
PopMedNet
PopMedNet Schema
- each source to maintain control of its data (sometimes referred to as “data lockers”)
- be capable of accepting and responding to queries.
- PopMedNet is intended to support medical product safety analysis
quiz 3
Quiz 4
quiz 5
Query Health
proposed Query Health architecture
distributed query standards.
Four kinds of standards:
- Envelope standards: define the package for sending/receiving queries
- Format standards: provide a Declarative specification of the query
- Results standards (such as QRDA): specify the format and packaging of the query results
- Data Model standards (such as CEDD common data element definitions): specify the data model that will link data from the contributing systems.
Standards
- Declarative specification: expresses the desired result.
- Procedural specification: provides a recipe for achieving the goal
- E.g. 1 Curly braces problem with the Arden syntax. Arden provides a declarative standard but the procedure will be different depending on the system that is the source of the data.
- e.g. 2 The hQuery Gateway receives a standard query on one side but knows how to get it done on the other.
Quiz 6
Query envelope standard
Query envelope standard
The Query Envelope standard serves to provide
- identification that is unique within the network;
- the information requestor ID including name, email and organization;
- the purpose, priority and type of the query
- 7 purpose codes (e.g. TREAT for treatment),
- its Priority from 1-5 (1 highest),
- its type Type, 1-20 characters
- PHI level (Aggregated, Limited, De-identified, PHI)
- its Timing, Submission date/time and optional execution date/time.
Query Format
Query Format: 3 levels of detail
Query Format: example
- the Health Quality Measure Format (HQMF): an HL7 standard format for documenting the content and structure of a quality measure in an XML document format based on the HL7 RIM.
- It can consist of three levels of detail:
- metadata: who wrote it, the dates over which it is valid, who validated it, and other details about how the measure works or is used;
- human narrative: measure description, data criteria, measure population and measure observations;
- computer instructions: how to count and compute the results of the measure.
- The example XML provides instructions to the computer to only include patients who have had a weight measured, presumably in the numerator of a weight screening quality metric that, as you should recall from Lesson 2, is a requirement of Meaningful Use.
the standard for query results
Query results
- QRDA in Lesson 8. Results can be reported at three levels of detail: patient-level, patient-list level or aggregate level.
- Example: the two result templates refer to NQF defined quality measures for inpatient asthma care.
Query Data Dictionary
the title here should have been **CEDD** Allergy Example
- The Clinical Element Data Dictionary (CEDD): use in setting up source data in support of distributed queries within a larger Query Health solution.
- it is not intended as a new standards development effort and began with the elements already specified in the CCD and which most EMRs already support
- Here’s a simple example for the patient allergy data element showing how it ties to already accepted standards used in the CCD.
quiz 7
Recap
In this lesson we
- examined how data from multiple EHR systems can be queried and aggregated for diverse purposes.
- e.g. quality reporting and advanced clinical research.
- All of these technologies provide a framework over the many non-interoperable EHR systems.
- Different technological solutions each of which is optimized for a specific problem in a specific cross-institutional context.
Supplementary resources
Key Concepts/Vocabulary
●Distributed query ● Distributed query standards ● Data warehouse ● Data lockers ● hQuery ● i2b2 ● PopMedNet ● Query Health ● Health Quality Measure Format (HQMF) ● Quality Reporting Document Architecture (QRDA)
Readings
- QDM Version 4.1 Specification
- QRDA Implementation Guide for category I and III reporting
Videos
- Query Health Initiative
- i2b2 demo
- i2b2 and PopMedNet integration
Graphics
- hQuery query screen
- Query Health pilot proposal
2015-10-19 初稿