The Northern Ireland Longitudinal Study: The Northern Ireland Longitudinal Study:

Current and Potential ProjectsCurrent and Potential Projects

NILS Research Support Unit:

Fiona Johnston

Michael Rosato

Dr Gemma Catney

1. Northern Ireland Longitudinal Study (NILS) – c. 28% representative sample of NI population (500,000 individuals), based on health card registrations, linked to:

2001 Census returns vital events (births, deaths and marriages) demographic & migration events contextual and area-based data:

• capital value of houses and property attributes• geographical indicators• settlement classifications• deprivation measures

Distinct Health & Care datasets

2. Northern Ireland Mortality Study (NIMS) - enumerated population at Census Day (c.1.6 million) linked to 2001 Census returns and subsequently registered mortality data

Introduction to the NILS and NIMS

Structure of the NILS

Datasets Routinely LinkedCensus Dataset 2001 GRO Vital Events Datasets 1997-2007

Variables include:Age, sex and marital status Religion and community backgroundFamily, household or communal typeHousing, including tenure, rooms and amenitiesCountry of birth, ethnicity Educational qualificationsEconomic activity, occupation and social classMigration (between 2000 and 2001)Limiting, long-term illness, self-reported general health, caregivingTravel to work

- New births into the sample - Births to sample mothers and fathers - Stillbirths to sample mothers - Infant mortality of children of sample mothers and fathers - Deaths of sample members 2001-2007 - Marriages 2004-2006 - Widow(er)hoods 2004-2006

LPS Property Data 2010 Health Card Registration Datasets 2001-2010

Capital and rating value (based on 2005 valuation exercise)

Variables include: - Household characteristics (no. of rooms, property type, floor space, central heating) and valuation - Estimated capital value

- Demographic data: age, status and location

- Migration events: immigrants added to the sample emigration of sample members re-entry of sample members to NI migration within NI

1. Research-Driven Cross-sectional studies: no information on change over time Other UK LS Health and socio-demographic profile

2. Legislation NILS confidentiality protected, and managed by NISRA, under census

legislation NISRA have consulted the following about NILS:

Information Commissioner for Northern Ireland Office of Research Ethics Health and Social Care Privacy Advisory Committee

3. Funding Infrastructure funded by the Health and Social Care Research and

Development Division of the Public Health Agency (HSC R&D Division) and NISRA

Support function funded by ESRC and NI Government (OFMDFM)

Background to the NILS and NIMS

Distinct Linkage Projects Potential to link to health services data for specially defined one-off studies;

so far successfully linked to Cancer Screening data and Dental Activity data

Legal and ethical scrutiny and privacy protection protocols:

Study period and specific data transfers agreed (DTA) Legal basis for data transfer (DTA) Health and Social Care Privacy Advisory Committee informed Ethics – database modification submitted for non-routine linkage (ORECNI)

One-way encryption methodology:

developed in Scotland to safeguard sensitive census and health and care data datasets are matched and merged on an encrypted unique identifier researchers not involved in the linkage processes; only have access to an

anonymised dataset

Over 40 projects currently based on NILS and NIMS databases including analyses on:

mortality (e.g. alcohol-related deaths; self-reported health and mortality); fertility (e.g. predicting short run changes; characteristics of lone parents); migration, rural communities and area influences on health.

A study of the socio-demographic and area correlates of suicides in NI* (005):results and conclusions from published paper

Influence of demographic, socio-economic and area level factors on uptake of routine breast screening in NI** (021): results first presented at SSM 2010 (PhD and submitted for publication)

*O’ Reilly, D., Rosato, M., Connolly, S. and Cardwell, C. (2008) Area factors and suicide: 5-year follow-up of the Northern Ireland population. Br J Psychiatry 192(2):106-11.

**Kinnear, H., Uptake of Breast Screening: Where You live Also Matters. Presented at Society for Social Medicine Conference , QUB, Sept 2010

Current Projects

Background:Suicide rates vary between areas: is this due to characteristics of people (composition) or to the characteristics of the area itself (context)?

Aim:To determine if area factors are independently related tosuicide risk after adjustment for individual and familycharacteristics.

Method:A 5-year record linkage study, based on the NIMS database, was conducted of c. 1.1 million non-institutionalised individuals aged 16–74 years, enumerated at the 2001 Northern Ireland Census. - data anonymised and held in a safe setting

Area Factors & Suicide (i)

Results:

1. The cohort experienced 566 suicides during follow-up.

2. Suicide risks:i. lowest for women and for those who were married or

cohabiting;ii. strongly related to individual and household disadvantage

and economic and health status.

3. The higher rates of suicide in the more deprived and socially fragmented areas disappeared after adjustment for individual and household factors.

4. There was no significant relationship between population density and risk of suicide.

Area Factors & Suicide (ii)

Conclusions:

Differences in rates of suicide between areas are predominantly due to population characteristics rather than to area-level factors, which suggests that policies targeted at area-level factors are unlikely to significantly influence suicides rates.

Paper published in British Journal of Psychiatry (2008)

Area Factors & Suicide (iii)

Suicide (Daily Mirror)

Background:Background: All women aged between 50-64 invited once every 3 years for breast All women aged between 50-64 invited once every 3 years for breast

screening in NIscreening in NI Current uptake rate in UK is about 76-77%Current uptake rate in UK is about 76-77% Uptake is lower in inner city areas (London ~ 64%)Uptake is lower in inner city areas (London ~ 64%)

Aim:Aim:To describe and explain demographic, socio-economic and area-level variations To describe and explain demographic, socio-economic and area-level variations

in in attendance at breast screening for women who were routinely invited during the attendance at breast screening for women who were routinely invited during the 2001-2004 period.2001-2004 period.

Method:Method:Linking of 2 highly sensitive datasets (NILS and Breast Screening data) andLinking of 2 highly sensitive datasets (NILS and Breast Screening data) andtherefore involved following processes:therefore involved following processes:

ORECNI ethical approvalORECNI ethical approval PAC commendationPAC commendation one-way encryptionone-way encryption all analyses carried out in NISRA – safe settingall analyses carried out in NISRA – safe setting

Uptake of Breast Screening

Age, marital status, general health

Demographic factors Uptake rates

50-54 78.1%

55-59 76.4%

60-64 70.9%

Married 78.0%

Never married 66.7%

Separated/widowed/divorced 67.5%

Good general health 77.6%

Fairly good 75.3%

Not good 68.1%

Housing tenure, car access, educ. & NSSEC

Socio-economic factors Uptake rates

Owner occupier 78.0%

Private renting66.9%

Social renting 61.3%

2+ cars 80.3%

1 car 74.9%

No car 60.1%

Employed 75.9%

Unemployed 63.9%

Settlement Bands (A-H) showed Belfast Metropolitan Area different from rest

Settlement bands (U,I,R) showed uptake lower in urban and highest in rural areas

Area Uptake rates

Belfast Metropolitan Area 68.3%

Rest of NI 78.7%

Eastern 70.1%

Northern 79.3%

Southern 78.3%

Western 78.1%

Inter-Censal Migration Flows

Mortality after death of a spouse: Is risk the same for all groups?

Religion, fertility and space: impacts on the future school population of Northern Ireland.

DLPs:

The Northern Ireland Electronic Prescribing and Eligibility System (EPES) data: use of antibiotics by demographic and area characteristics (approved)

Northern Ireland Cancer Registry data (feasibility discussions in place)

Future and Pending Projects

The help provided by the staff of the Northern Ireland Longitudinal Study and the Northern Ireland Mortality Study (NILS and

NIMS) and the NILS Research Support Unit is acknowledged.

The NILS and NIMS are funded by the Health and Social Care Research and Development Division of the Public Health

Agency (HSC R&D Division) and NISRA. The NILS-RSU is funded by the ESRC and Northern Ireland Government.

The authors alone are responsible for the interpretation of the data.

Acknowledgements

NILS Research Support UnitNorthern Ireland Statistics and Research Agency

McAuley House2-14 Castle Street

BelfastBT1 1SA

 Tel: 028 90 348138

Email: nils-rsu@qub.ac.uk Website: nils-

rsu.census.ac.uk