Chris Munt :: State Of Play In the NHS

The state of play in NHS IT Chris Munt Cherylin Fletcher Royal Marsden NHS Trust

Agenda: Part I
Healthcare IT
A local view
IT at the RMH
Cherylin Fletcher
(Deputy Director of IT at RMH)

Agenda: Part II
Caché at the RMH
Building a successful IT infrastructure to support heathcare applications
Chris Munt

RMH IT – History (80s)
Department formed in early 1980s
General hospital IT
Research
One of the first UK customers for DSM
DEC PDPs
Moved to M11+ and MVX in mid 80s
Operational Systems
DEC PDPs – 11/70, 11/44
Research system (epidemiology, analysis)
DEC VAX 11/750

First applications – the basics
Patient Master Index
Basic pathology (Chemistry, Haematology)
Admissions and Outpatients
Third party pharmacy system
Clinical Research System (CRS)
Significant hardware upgrade late 80s
VAX 8530

Seduced by cost/performance of RISC based architecture
Migrate from VAX/VMS to HPUX on HP hardware
Switched to Micronetics MUMPS (MSM)
Later switched back to InterSystems M (ISM)
Further applications
Towards a complete PAS and HIS
Radiology and other clinical systems

Turbulent times ahead
National Programs on the horizon
Poor image of M-based systems in NHS
Despite the fact that they delivered (and many are still doing so now!)
Experimented with various standard RDBMS
Further third party departmental systems introduced
Standardized core on InterSystems Caché
Natural ‘best fit’ successor to our M-based systems.
Caché 5 on IBM AIX
Development machine
Operational machine + Shadow

RMH IT – Architecture
1980s: Terminal based applications
Serial lines to server
1990s: Migrating to Windows/GUI
Terminals replaced with PC workstations
Workstations networked (LAT then TCP)
VB applications
Using an adaptor to M (developed in-house)
Used telnet to M and TCP sockets when they became available
Likely to be one of the first service oriented (non-ODBC) connectors between VB and M
Later applications used HTTP over WebLink

RMH IT – Architecture
2000s: Migrating to the Web
All workstations networked (TCP)
Visual InterDev with VB
ASP.Net
Using WebLink and CSP as the transport
Web services in CSP
Proprietary protocols over HTTP

RMH IT – Development
Early systems
Hand-crafted M code
Needed to improve quality, resilience and maintainability
Various experiments with code generators
Tools for screen design
Developed ETHOS toolkit
E x T ended H igher O rder S oftware
HOS (Higher Order Software) + SQL/RDBMS
HOS: Programming environment
SQL/RDBMS: Added to the HOS environment to make ETHOS in mid-80s
Likely to be first SQL implementation for M

ETHOS: HOS Component
What is it?
Mathematically verified Functional Programming Environment
Underlying Mathematics by Margaret Hamilton and Saydean Zeldin
A Methodology for Defining Software
Developed for the Apollo and Skylab programs
Graphical tree-based representation of functions
Partial functions with plug-in points
Defined Structures

ETHOS: HOS Component
Benefits?
Integrity of tree structures checked for self consistency and correctness
Interfaces verified
Referential transparency
Self documenting
Tree nodes separate the ‘what’ from the ‘how’ of an operation
Generates bug-free code

ETHOS
Higher Order Software
Some Examples

ETHOS tree: Calculate Age

ETHOS tree: Embedded SQL

ETHOS tree: Recursion

ETHOS tree: Using Libraries

ETHOS: SQL/RDBMS Component
What is it?
SQL with extensions
ETHOS functions can be embedded in SQL and vice versa
Sequences
Complex derivations
Best of Caché incorporated (e.g. pattern match)
Comprehensive Data Model
Definition of Entities (tables/classes) and Attributes (fields/properties)
ETHOS Entity == RDBMS Table == Caché class
Derived attributes and tables
Inheritance and polymorphism
Full referential actions (e.g. maintenance of referential integrity)

ETHOS: SQL/RDBMS Component
Benefits?
High level of abstraction
Object-relational characteristics
Derived supersets maintained in real time
Data warehouse
Rich environment for data analysis
Support for research
Multiple access paths to same data
SQL accessible Cache classes maintained in parallel
ETHOS SQL
Caché SQL
Caché Objects
M Globals

ETHOS
SQL and Data Model
Some Examples of Entity Definitions

ETHOS Entity: PATIENT
Base Table: Primary View
SELECT PAT-NUM, PAT-NAM, ADDRESS, D-REG, T-REG, D-BIRTH, AGE,
D-LAST-ADM
FROM [BASE-TABLE]
DECLARE PAT-NUM ::= BT ;
DECLARE PAT-NAM ::= BT ;
DECLARE ADDRESS ::= BT ;
DECLARE D-REG ::= BT <- DATE.VALUE ;
DECLARE T-REG ::= BT <- TIME.VALUE ;
DECLARE D-BIRTH ::= BT <- DATE.VALUE ;
DECLARE AGE ::= SV <= AGE:LX(D-BIRTH) ;
DECLARE D-LAST-ADM ::= HV <= GET_LAST_ADM_DATE:LX(
F:ADMISSION,
PAT-NUM)
<- DATE.VALUE ;

ETHOS Entity: DATE
Superclass of all attributes of type ‘DATE’
SELECT VALUE, ENCODE, DECODE
FROM [BASE-TABLE]
DECLARE VALUE ::= SV ;
DECLARE ENCODE ::= SV <= ENCODE_DATE:LX(:DECODED-DATE) ;
DECLARE DECODE ::= SV <= DECODE_DATE:LX(:ENCODED-DATE) ;

ETHOS Entity: ADMISSION
SELECT PAT-NUM, D-ADM, T-ADM, WARD
FROM [BASE-TABLE]
DECLARE D-ADM ::= BT <- DATE.VALUE ;
DECLARE T-ADM ::= BT <- TIME.VALUE ;
DECLARE WARD ::= BT <- WARD.WARD-ID ;

ETHOS Entity: DIAGNOSTICS
SELECT PAT-NUM, D-TEST, T-TEST, TEST-ID, RESULT
FROM [BASE-TABLE]
DECLARE D-TEST ::= BT <- DATE.VALUE ;
DECLARE T-TEST ::= BT <- TIME.VALUE ;
DECLARE TEST-ID ::= BT <- LAB-TEST.TEST-ID ;
DECLARE RESULT ::= BT ;

ETHOS Entity: EVENTS
Derived Table: Primary View
SELECT PAT-NUM, D-EVENT, T-EVENT, KEYS, EVENT-TYPE
FROM [BASE-TABLE]
DECLARE D-EVENT ::= BT <- DATE.VALUE ;
DECLARE T-EVENT ::= BT <- TIME.VALUE ;
DECLARE KEYS ::= BT ;
DECLARE EVENT-TYPE ::= BT ;

ETHOS Entity: EVENTS (1)
Derived Table: Secondary View 1 (Contribution from PATIENT)
FROM PATIENT
DECLARE PAT-NUM ::= HV <= PATIENT.PAT-NUM ;
DECLARE D-EVENT ::= HV <= PATIENT.D-REG ;
DECLARE T-EVENT ::= HV <= PATIENT.T-REG ;
DECLARE KEYS ::= HV <= K:PATIENT ;
DECLARE EVENT-TYPE ::= HV <= "REGISTRATION" ;

Derived Table: Secondary View 2 (Contribution from ADMISSION)
FROM ADMISSION
DECLARE PAT-NUM ::= HV <= ADMISSION.PAT-NUM ;
DECLARE D-EVENT ::= HV <= ADMISSION.D-ADM ;
DECLARE T-EVENT ::= HV <= ADMISSION.T-ADM ;
DECLARE KEYS ::= HV <= K:ADMISSION ;
DECLARE EVENT-TYPE ::= HV <= "ADMISSION" ;

Derived Table: Secondary View 3 (Contribution from DIAGNOSTICS)
FROM DIAGNOSTICS
DECLARE PAT-NUM ::= HV <= DIAGNOSTICS.PAT-NUM ;
DECLARE D-EVENT ::= HV <= DIAGNOSTICS.D-TEST ;
DECLARE T-EVENT ::= HV <= DIAGNOSTICS.T-TEST ;
DECLARE KEYS ::= HV <= K:DIAGNOSTICS ;
DECLARE EVENT-TYPE ::= HV <= "DIAGNOSTICS" ;

ETHOS SQL: Sequences
“ Get all diagnostic tests performed for a patient between 9:00 on 1/9/07 and 12:00 the following day”
SELECT *
FROM DIAGNOSTICS A:SEQUENCE(PAT-NUM, D-TEST, T-TEST)
WHERE A AFTER :PAT-NUM, “1/9/07”, “9:00”
AND A BEFORE :PAT-NUM, “2/9/07”, “12:00”

RMH IT/ETHOS – Why Caché?
High Performance
Rapid Application Development
Massive Scalability

High performance?
Undoubtedly true
Fastest high-end database that we’ve used
Low hardware costs
Small investment can make a ‘slow’ DBMS perform well
Free alternatives
Many will put up with a non-optimal solution if it is free.

Rapid Application Development?
Undoubtedly true
Others make the same claim
Free alternatives
Many will put up with a non-optimal solution if it is free.

Massive scalability?
Undoubtedly true
We’ve migrated systems from PDP 11s to high end IBM/AIX servers to PCs
Low administrative costs
Well abstracted environment
Low hardware costs
Modern networking
Clustered and/or distributed environments
Load balancing solutions

Free Alternatives
OpenSource, FSF, Freeware etc …
Will it really take over the world?
What drives development?
Research initiatives
Outsource support
Consulting based marketing model

Free Alternatives
OpenSource, FSF, Freeware etc …
Will it really take over the world?
What drives development?
Research initiatives
Outsource support
Consulting based marketing model
The presence of a ‘Bogeyman’ as a motivator
The bigger the better
Free software thrives on a healthy commercial sector

Traditional Project Lifecycle
Analysis of requirements
Design data-model
Know requirements in advance
Design model with reports in mind
Create application
Maintenance and compromise
De-normalize database to make it perform

Systems Development
May not want to implement something as big as ETHOS but …
The case for having a more flexible environment than is usually provided by a conventional DBMS is compelling
Never know requirements in advance
Web culture demands flexibility
ever changing requirements
Higher expectations
Applications need to adapt and evolve
Without driving up costs and complexity

HTTP
SOAP, REST, MEST, [2008 version] etc … are transported by HTTP and …
The case for having a comprehensive development environment for serving protocols carried over HTTP is compelling
Ajax allows web applications to distribute processing to clients
Not available to the infrastructure for data communication/distribution
Higher expectations for integration/sharing
Complex functionality behind services
Applications need to reach out and be available to foreign systems
Without driving up costs and complexity

Caché in Healthcare IT
High Performance
Rapid Application Development
Massive Scalability
Excellent Systems Prototyping and Development Environment
Excellent back-end processor for HTTP

The state of play in NHS IT Chris Munt Cherylin Fletcher Royal Marsden NHS Trust

Chris Munt :: State Of Play In the NHS

by george.james on Sep 28, 2007

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