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Background and Methodology

Background and Methodology

CSO statistical publication, , 11am

This publication is categorised as a CSO Frontier Series Output. Particular care must be taken when interpreting the statistics in this release as it may use new methods which are under development and/or data sources which may be incomplete, for example new administrative data sources.

Protected Identifier Keys

Before using personal administrative data for statistical purposes, the CSO removes all identifying personal information. This includes the Personal Public Service Number (PPSN), a unique number used by people in Ireland to access social welfare benefits, personal taxation and other public services. A pseudonymised Protected Identifier Key (PIK) is created by the CSO when the PPSN is removed. This PIK is unique and non-identifiable and is only used by the CSO.

Using the PIK enables the CSO to link and analyse data for statistical purposes, while protecting the security and confidentiality of the individual data. All records in the matched datasets are pseudonymised and the results are in the form of statistical aggregates which do not identify any individuals.

Cohorts

Children in care in January 2023

The cohort of children and young people in care in January 2023 includes all children and young people, aged between 0 and 17 years, who were on a care placement on 16 January 2023. These children and young people must have had a referral to Tusla, which led to an admission to care (and the creation of a care record) prior to January 2023 to be included.

Note that 52 of the young people in the cohort turned 18 during January 2023, however as date of birth data is pseudonymised to month of birth, their age was set to 17 for the analysis.

Children who left care since April 2018

The cohort of children and young people who left care since April 2018 includes all children and young people who had one or more care placements between April 2018 and January 2023. It does not include children and young people who were on a care placement after the 16 January 2023. The cohort includes children and young people from under 1 to 23 years of age (a young person aged 18 in January 2018 would be 23 years old in January 2023).

Children who left care aged 18 to 22 (Chapter 5. Outcomes for children who left care aged 18 to 22)

Young people who left care between April 2018 and 16 January 2023 and aged between 18 and 22 by January 2023. There were very few records of young people aged 23 within this cohort, so due to statistical disclosure controls this age was excluded from the outcome analysis in Chapter 5.

Children in care (all)

The children in care (all) cohort comprises all children and young people in care in January 2023 and all children and young people who left care since April 2018.

All Children

The all children cohort is based on available data from the relevant primary school enrolment records for academic years 2015/16 to 2021/22, post primary enrolment records for the academic years 2012/12 to 2021/22 and those children whose parents/guardians were in receipt of Child Benefits payments since 2015.

Data sources

National Childcare Information System (NCCIS)

Data on children in care as of January 2023 was provided by Tusla from the National Childcare Information System (NCCIS). Note that the data excludes children falling under the Social Work Team for Separated Children Seeking International Protection.

In 2018 Tusla’s National Child Care Information System (NCCIS), an integrated case management system which managed child protection and welfare and children in care data, was rolled out nationally across Tusla’s 17 administrative areas. The NCCIS greatly improved the integrity and consistency of the data collected as prior to its advent Tusla areas relied extensively on a variety of legacy, often paper based, systems. In February 2023, the NCCIS migrated onto Tusla’s new case management system Tusla Case Management, Child Protection and Welfare (TCM, CPAC).

Tusla Education Support Service (TESS)

Data on school absences for over 20 days during the academic year 2018/19. Data provided by Tusla Education Support Service (TESS).

Primary Pupils Database (POD)

Contains data on each student enrolled in each recognised primary school collected by the Department of Education. This report utilises the available enrolment data for academic years 2015/16 to 2021/22.

Post-Primary Pupils Database (PPPDB)

The Post-Primary Pupil Database is currently the only national archive of student enrolment at post-primary schools. Individual and personal data on each student enrolled in each recognised post-primary school are collected by the Department of Education. This report utilises the relevant enrolment data for academic years 2012/13 to 2021/22.

PAYE Modernisation (PMOD)

The real time PMOD dataset contains payslip information of persons in employment and on occupational pensions since 01 January 2019.

Programme Learner Support System (PLSS)

The Programme Learner Support System (PLSS) is used to manage course information, learner records and reporting by SOLAS (an tSeirbhís Oideachais Leanúnaigh agus Scileanna), the Further Education and Training Authority. They provide a clear, integrated pathway for learners seeking to enrol in further education and training. 

Central Records System (CRS)

The Central Records System (CRS) is a legacy system within the Department of Social Protection (DSP) which holds data on their customers.

DSP Payments

Department of Social Protection’s database from the Business Object Model implementation (BOMi) and Integrated Short-Term Payments System (ISTS) contains information on welfare payments, including state pension, unemployment benefit and child benefit (adults only).

ITForm11

The ITForm11 contains the annual income tax returns of the self-employed from Revenue. Data for a calendar year is only complete three years after the reference year, because of the nature of self-assessment, although the majority of records are available about two years after the reference year.

Child Benefit (CB)

The Child Benefit dataset contains information on Child Benefit payments to parents/guardians of eligible children.

Quality and Qualifications Ireland (QQI)

QQI is an amalgamation of the previously operational Further Education and Training Awards Council (FETAC); the Higher Education and Training Awards Council (HETAC); the Irish Universities Quality Board (IUQB) and the National Qualifications Authority of Ireland (NQAI).

Higher Education Authority (HEA)

The Higher Education Authority data provides details on annual enrolments and graduations from the publicly funded universities and institutes of technology in Ireland.

Springboard

HEA Springboard and ICT provides information on students who have undertaken HEA springboard or ICT courses. This data includes course details and basic demographic information for enrolled students, with identifying data removed or pseudonymised. Springboard is available to 2019.

Student Universal Support Ireland (SUSI)

Student Universal Support Ireland contains funding information for all higher and further education grants. SUSI offers funding to eligible students in approved full-time, third-level education.

Classification - Legal Status

The legal status in this release is the most recent legal status, e.g., care order type, either the status in January 2023 or the last status before leaving care:

Care Order

A care order is applied for when a child needs protection and is unlikely to receive it without the use of one.  A care order is usually made for as short a period as possible. If necessary, the Court may decide to place a child in care up to their 18th birthday.

Emergency Care Order

Tusla applies for an emergency care order when there is reasonable cause to believe that there is an immediate and serious risk to the health or welfare of a child.

Interim Care Order

Tusla applies for an interim care order where an application for a care order has been or is about to be made and, there is reasonable cause to believe that it is necessary for the child’s health or welfare, for the child to be placed or maintained in the care of Tusla.

Voluntary care arrangement

This is where the parents request or agree to their child being taken into the care of Tusla.

Classification - Placement type

The placement type in this release is the most recent type e.g., general foster care, either in January 2023 or the last status before leaving care:

General foster care

The child is placed with a person approved by Tusla, who is not related or known to the child (see Relative foster care).

Relative foster care

The child is placed in the care of a friend, neighbour or relative, or a person with whom the child or the child’s family has had a relationship prior to the child’s admission to care and who is approved by Tusla.

Residential general care

The child is placed in a home or institution for the residential care of children. Residential care can be provided by statutory, voluntary or private providers.

Residential special care

Special care provides for short-term, stabilising intervention that prioritises safe care in a therapeutic environment for children at risk and with challenging behaviour. It is an exceptional intervention restricting the liberty of the child and involves detention of the child for his/her own welfare and protection in a special care unit.

Education statistics

Primary pupils in special schools or with special needs in mainstream national schools

The Department of Education (DoE) publishes data on primary pupils with special needs. In the academic year 2021/22 there were 8,740 primary pupils in a special class attached to mainstream national schools, and 8,686 primary pupils were enrolled at a special  school. Hence a total of 17,422 primary pupils were enrolled at special schools or with special needs at mainstream national schools. Note that the DoE published figures include all enrolments, including those unsuccessfully and successfully linked by the CSO to other pseudonymised administrative data sources using PIKs.

Repeating a school year

The DoE publishes data on mainstream primary pupils repeating a year at primary school. In the academic year 2021/22, there were 1,915 children or 0.3% of all children enrolled at primary school (see bulletin for 2021/22 figures) repeating a primary school year.

Due to the size of the children in care cohort and statistical disclosure controls in place, figures for a single academic year cannot be published. For this report, and to facilitate the cohort size and wide age range of the cohort, a second, experimental statistic was developed where a child is identified as a having repeated a school year if there are two identical enrolments in two consecutive years in either the Primary Pupils Database (POD) over the academic years 2015/16 to 2021/22 or the Post-Primary Pupils Database (PPPDB) over the academic years 2012/13 to 2021/22. Only mainstream primary pupils and primary schools are included in the primary count. Note that the data excludes private schools that do not receive funding from the Department of Education.

Changing schools

The DoE publishes data on primary school entrants to mainstream classes from other primary schools within the State. In 2021/22 there were 21,203 children who entered primary mainstream classes from other national primary schools, was equivalent to 4% of all enrolments. Note that the DoE published figures includes all enrolments, including those unsuccessfully and successfully linked by the CSO to other pseudonymised administrative data sources using PIKs.

While a figure for 2021/22 using the same methodology is part of the release (Table 3.4) for pupils changing from one primary school to another, it does not give any information on older children in care.

Hence a second experimental statistic was developed where a child was identified as changing schools if they were enrolled in two schools over two different academic school years in either the Primary Pupils Database (POD, independent of school type) or the Post-Primary Pupils Database (PPPDB), see Table 3.5.  A change from primary to post primary school is not counted as a school change. Note that the data excludes private schools that do not receive funding from the Department of Education.

Early leaver

An early school leaver is a pupil within an entry cohort to post primary education (enrolled in 1st year of the Junior Certificate or the junior certificate schools programme) who does not sit their Leaving Certificate within five or six years based on SEC data and no longer appears in the secondary school enrolment dataset.  As an example, children starting the first year of post-primary in September 2013 who did not sit the Leaving Certificate 2019 would be considered an early leaver.

The DoE publishes the Retention Report on early school leavers. As an example, the retention rate to the Leaving Certificate stood at 92.1% for the 62,248 pupils of the 2015/2016 entry cohort i.e., were 4,912 pupils left school early. Note that the DoE published figures include all pupils, including those unsuccessfully and successfully linked by the CSO to other pseudonymised administrative data sources using PIKs.

For the analysis on children in care and all children, entry cohorts 2012to 2015 are included in this release. The early leaver data and entry cohort is sourced from the Post-Primary Pupils Database (PPPDB). The PIK coverage of the early leaver’s dataset was 93% for the 2015 entry cohort. Hence the total size of the entry and early leaver cohort for all children in this report is lower than what is published in the DoE’s Retention Report as the former concerns children aged 23 and under included in the comparison ‘all children’ cohort that could be matched via a PIK only.

Student Absence

Tusla publishes an annual Analysis of School Attendance data. Included are statistics on pupils missing 20 or more days of school in an academic year. Student Absence Reports were recorded for 43,425 primary school pupils and 22,431 post-primary school students for the academic year 2018/2019, which is also the academic year reported in this report.

Outcome Definitions

Substantial Employment

An individual is regarded as being in 'substantial employment' within a given calendar year if they fulfil either of the criteria A or B below.

A. Substantial P35 employment: They fulfil the following 2 requirements:

  1. They have at least 12 weeks of insurable work within the calendar year across all employments. This can be supplemented by weeks of maternity leave and/or illness leave;
  2. The average weekly earnings from their main employer only is at least €100 per week.

B. Substantial self-employment: Their total turnover across all self-employment activities is at least €1,000 within the calendar year.

Education

An individual is regarded as being 'in education' within a given calendar year if they fulfil either of the criteria A or B below:

A. Enrolment in primary or post-primary school. Due to the age of the children in care, many are still enrolled in post-primary school over the period 2019-2021 analysed in this release. A proportion of children are enrolled in special schools falling under primary enrolments, and hence primary enrolments are also included here. Enrolment was examined using the Primary Pupils Database and the Post-Primary Pupils Database.

B. Enrolment in higher or further education: The person has a record of enrolment in higher or further education in the year in question. Enrolment was examined using QQI, SOLAS, SUSI and HEA (includes Springboard to 2019) data sources.

An individual may be enrolled in both post-primary and higher education within the same calendar year. However, this is not necessarily at the same time as the calendar year spans two academic years. For example, an individual may be enrolled in their final year in post-primary in the first half of the calendar year and be enrolled in higher education in the latter half of the year.

The type of educational enrolment in Section 5.3 is ranked and the highest is chosen if there are multiple types of enrolment in the calendar year. The ranking is as follows:

1. Higher education (HEA) enrolment

2. Further education (SOLAS PLSS) enrolment

3. School enrolment

Not Identified and Neither Employment nor Education

Where a person was neither in substantial employment nor enrolled in education within a specific calendar year, then they may be assigned to one of two remaining categories: 'neither employment nor education' and 'not identified'. A person is assigned to 'neither employment nor education' if they appear in any of the datasets for that year without being classified as being in substantial employment or enrolled in education. 

A person is assigned to the category of 'not identified' if they do not appear in any of the administrative datasets for that year and have no recorded activities such as those listed above.