Individual Referencing Systems Anthea Springbett Programme Principal SHIS-R NHS Information Services Division
Structure of workshop Introduction Referencing and linkage ISD linkage CHI Practical application of CHI Population spine Future
What is individual referencing? Administrative systems organising information retrieving information Audit Linking information over time across space
ISD: collecting data from cradle to grave Dental SMR13 Mental Health SMR04 Scottish Birth Record SBR Out patients SMR00 Hospital Admissions SMR01 BIRTH GP consultations Maternity Immunisation Prescribing Screening Cancer registry DEATH Child health surveillance A&E Cancer registrations SMR06
From conception through childhood... Mothers ante-natal records Abortion Notifications Maternity CHI Number Neonatal record Register birth - NHS number Register with GP Child-health surveillance Immunisation GP Appointments Dental Appointments Outpatients
adulthood until death Outpatients A&E attendance General hospital admission Prescribing Well woman/man screening Cancer registration Cancer treatment Audit of clinical treatment Stroke - hospitalisation & rehab Community care Death
Why is referencing so useful for linkage? Data collection systems point of delivery episodic many sources different protocols variable data quality
What is the alternative? Personal information name address date of birth Contextual information date/time of admission
What are the advantages of referencing? Simplicity Privacy Consistency Flexibility Efficiency
and what are the disadvantages? Completeness Accuracy Maintenance Fraud
ISD: collecting data from cradle to grave Dental SMR13 Mental Health SMR04 Scottish Birth Record SBR Out patients SMR00 Hospital Admissions SMR01 BIRTH GP consultations Maternity Immunisation Prescribing Screening Cancer registry DEATH Child health surveillance A&E Cancer registrations SMR06
CHI (Community Health Index) Scottish Introduced first in Tayside Assigned at birth Coverage all NHS patients Maintenance PSD Used by ISD for linkage
Record linkage in ISD History 1960s: routine recording of patient identifiers 1970s: linkage programs 1980s: permanently linked datasets 1990s: CHI Probability Matching Quantifies the quality of a potential match Enables routine linkage of datasets Use of CHI in linkage Unique patient identifier for each patient Protects patients privacy Efficient
Linking records (Donald Duck and Daisy Swan) Surname Soundex Forename Date of birth Post code CHI number Duck D200 Donald 1 January 1955 DL1 2BY 0101551234 Dukk D200 Donald 1 January 1955 DL2 3SL 0101551234 Surname Soundex Forename Date of birth Post code CHI number Swan S500 Daisy 24 December 1959 AZ1 2BY 2412591234 Duck D200 Daisy 24 December 1959 DL2 3SL 2412591234
Cross-referencing
Population spine Master index Independent systems Read-through across systems Data obtained from several systems Linkage only as required
Example of recent ISD linkage T4 HEAT target to reduce emergency admissions Linkage of NHS24, SAS, ACaDMe, Out of Hours and A&E admissions National linkage to replace local data Follow patient pathways Partial CHI coverage
The future (1) - SHIP Scottish Health Informatics Programme Funded by Wellcome Trust, MRC, ESRC Academic/NHS consortium 2009/10 to 2012/13 SHIP is: an ambitious, Scotland-wide research platform for the collation, management, dissemination and analysis of Electronic Patient Records (EPRs)
ISD s contribution to SHIP (SHIS-R) Procedures for secure access Linkage agent and safe haven National routine NHS Scotland datasets available to researchers throughout UK Portal for knowledge about availability of appropriate health related data Archiving Metadata Indexing service
Datasource 1 Datasource 2 Project code Local IDs Study numbers Local IDs Names Addresses Dates of birth Local IDs Names Addresses Dates of birth Project code Local IDs Study numbers Indexing Service Datasource 1 Indexing service sends key to Linkage Agent within Safe Haven Datasource 2 Project code Study numbers Payload data Linkage Agent within Safe Haven Project code Study numbers Payload data Payload data Project code Study numbers Payload data
Indexing service The indexing service uses CHI as a population reference file Use of a population reference file maximises leverage of linkage The indexing service does not release CHI numbers or CHI data but only index numbers Different sets of index numbers are used for each data set to be linked Identifiers and payload data are always kept separate
The role of the research coordinator Data permissions Data release Non-NHS Data controller National PAC (ISD, GROS) Local PAC or equivalent (NHS HB) Non-NHS dataset ISD dataset Local HB dataset Data request Research Coordinator Referral of data request National Indexing Service Linker (NSS) Creation and storage of linked dataset Advice & guidance Training Researcher approval Safe haven Researcher approval and secure access
The future (2) - NDLC National Data Linkage Centre ISD and NRS Cross-sectoral data linkage Utilising existing expertise Population spine B2011
Sail gives way to steam