Implementation status of Ruby implementation of openEHR, the openEHR developers' workshop, MEDINFO2015, Sao Paolo, Brazil, 2015

1. Ruby on the openEHR
Shinji KOBAYASHI

2. Ruby implementation of openEHR
● Done
– RM, AM
implementatio
n
– ADL 1.4
parser
– Archetype to
Rails app
● Doing
– OPT parser
– Rails Engine
for openEHR
– Sample app
for our next
generation
EHR
● To do
– Terminology
(ontology)
flattener
– ADL 2.0
parser
● RR
grammar

3. Dolphin project
● Union of regional health care system
– Kyoto, Miyazaki, Kumamoto, Tokyo
– Web based system for hospitals and patients.
● Standardised by MML
– XML standard for sharing clinical information
– 22 XML formalism
● 12 years history
– Mainly coded by Perl and M(Mumps).
– DB Engine is Cache(TM).

4. rDolphin Project
● Revised Dolphin
– Modernise architecture. → MVC Framework
– Object oriented programming, Cache to RDBMS(or
NoSQL)
● Research Dolphin
– For implementation research of openEHR
– For clinical research
● Ruby Dolphin
– Ruby and Ruby on Rails implementation

5. Implementation overview
● Ruby on Rails(Ruby 2.2.3, Rails 4.2)
● Re-construction of MML by archetype concept
models
– Hand generated forms and classes
● PostgreSQL database engine
● Open Source Software

6. Logical model of Ruby classes
Person
Party
Organization EHR Composition
ContentItem
ContentItem
ContentItem
ContentItem

7. Database model

8. Performance benchmark(1)
MySQL 患者数 10 患者数 100 患者数1000
Vital sign report: 10 8.85 60.757 657.42
Vital Sign report: 100 59.241 580.31 5829.14
Vital Signレポート数 1000 580.29 5794.37 58019.49
PostgreSQL 患者数 10 患者数 100 患者数1000
Vital signレポート数 10 9.085 60.62 582.21
Vital Signレポート数 100 67.36 585.96 6010.87
Vital Signレポート数 1000 678.78 5827.74 58819.23
sqlite3 患者数 10 患者数 100 患者数1000
Vital signレポート数 10 20.229 162.74 1610.13
Core i7 4770, 3.4GHz, RAM 32GB, SSD 250GB, FreeBSD(64bit), ZFS Ruby 2.1.1

9. Performance bench mark(2)
Document
size
Concurrent
access: 1
Concurrent
access: 10
Concurrent
access: 100
HTML 8,500bytes 29.99 30.35 30.15
XML 812bytes 104.62 104.48 106.22
JSON 172bytes 108.83 109.08 107.01
CSV 16bytes 140.74 146.85 143.93
HTTP server: unicorn 4.8.3,
CPU Core i7 4770, 3.4GHz, RAM 32GB, SSD 255GB
Measured by Apache bench to localhost. Unit: request/second.
Each result was the avarage of 1,000 trials

10. Further works
● Rails Engine
– Auto-generation from OPT(Operational Template) to
● Web forms
● DB schema
● Ruby codes for models, controllers, views on Rails
● Javascripts and CSSs
● DB Engine
– RDBMS: PostgreSQL, MySQL
– NoSQL: Google Big Table, Hadoop