National Core Maternity Indicators: PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2019

Identifying and definitional attributes

Metadata item type:Indicator
Indicator type:Indicator
Common name:

Instrumental vaginal birth for selected females giving birth for the first time

Short name:PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2019
METeOR identifier:717542
Registration status:Health, Standard 19/06/2019
Description:

The proportion of selected females giving birth for the first time who gave birth by instrumental vaginal birth.

Rationale:

This indicator is used to benchmark practice.

Indicator set:National Core Maternity Indicators, 2019 Health, Standard 19/06/2019

Collection and usage attributes

Population group age from:

20 years

Population group age to:

34 years

Computation description:

The number of selected females giving birth for the first time who gave birth by instrumental vaginal birth, divided by all selected females, and multiplied by 100.

Selected females criteria: Females included are those who gave birth for the first time and met all of the following criteria:

  • aged between 20 and 34
  • gestational age at birth between 37 and 41 completed weeks
  • pregnancy has one baby only (singleton)
  • the presentation of the baby is vertex (baby's head was at the cervix).

Excluded are those females who have given birth prior to the current birth or did not meet the selected females criteria.

A birth is defined as the event in which a baby comes out of the uterus after a pregnancy of at least 20 weeks gestational age or weighing 400 grams or more.

Gestational age is a clinical measure of the duration of the pregnancy. For the National Perinatal Data Collection gestational age is reported as completed weeks.

An instrumental birth is a procedure that uses instruments (forceps or vacuum extraction) to assist the baby to come out through the vagina.

Computation:

100 × (Numerator ÷ Denominator)

Numerator:

The number of selected females giving birth for the first time who gave birth by instrumental vaginal birth.

Numerator data elements:
Data Element / Data SetBirth event—birth method, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetBirth event—birth plurality, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetProduct of conception—gestational age, completed weeks N[N]
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetFemale—parity, total pregnancies N[N]
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetPerson—date of birth, DDMMYYYY
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetBirth event—birth presentation, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Denominator:

All selected females.

Denominator data elements:
Data Element / Data SetPerson—date of birth, DDMMYYYY
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetBirth event—birth plurality, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetProduct of conception—gestational age, completed weeks N[N]
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetBirth event—birth presentation, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetFemale—parity, total pregnancies N[N]
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Disaggregation:
  • Year of birth
  • State or territory of birth
  • Hospital annual number of births
  • Hospital sector
  • Remoteness category (from mother's area of usual residence)
  • Indigenous status of mother.
  • Primary Health Network (from mother's area of usual residence)
  • Statistical local area 3 (from mother's area of usual residence)
Disaggregation data elements:
Data Element / Data SetBirth event—state/territory of birth, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetPerson—Indigenous status, code N
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetData Element

 Patient election status


Data Source
AIHW National Perinatal Data Collection (NPDC)
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetPerson—date of birth, DDMMYYYY
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetData Element

Hospital annual number of births


Data Source
AIHW National Perinatal Data Collection (NPDC)
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetPerson—area of usual residence, statistical area level 2 (SA2) code (ASGS 2016) N(9)
Data Source
Perinatal National Minimum Data Set (NMDS)
NMDS / DSS
Perinatal NMDS 2014-18
Guide for use

Data source type: Administrative by-product data


Data Element / Data SetData Element

Hospital sector


Data Source
AIHW National Perinatal Data Collection (NPDC)
Guide for use

Data source type: Administrative by-product data


Comments:

Data elements are from the Perinatal National Minimum Data Set (NMDS) or have been provided as voluntary non-standardised items by the states and territories. Records with data that are missing, not stated or not interpretable have been excluded from the denominator.

For Tasmania from 2005 to 2012, presentations via caesarean births were not reported by hospital still using paper-based form. Where a caesarean section occurred the presentation was recorded as 'Not stated'. Presentations via caesarean births was included in the paper-based form from 1 January 2013. As a result, Tasmania can only be reported 2013 onwards for selected females. The year 2004 was not included in this analysis as trend for after this year could not be undertaken due to the above issue.

Data for parity, a criteria to selected females, were not available from Victoria in 2009.

Patient election status is available for all jurisdictions from 2006.

Source of definition: Australian Council on Healthcare Standards (ACHS) Indicator 1.3: Selected women giving birth for the first time who undergo an instrumental birth. The ACHS define an instrumental birth as the use of forceps or vacuum. This ACHS indicator is based on the definition by Women's Healthcare Australasia Core Maternity Indicators Project (WHA 2007).

Representational attributes

Representation class:Percentage
Data type:Real
Unit of measure:Person
Format:

N[NN.N]

Data source attributes

Data sources:
Data SourcePerinatal National Minimum Data Set (NMDS)
Frequency
Annual
Data custodian

Australian Institute of Health and Welfare



Data SourceAIHW National Perinatal Data Collection (NPDC)
Frequency
Calendar years ending 31 December each year
Data custodian

Australian Institute of Health and Welfare


Source and reference attributes

Submitting organisation:

Australian Institute of Health and Welfare

Reference documents:

ACHS (The Australian Council on Healthcare Standards, Health Services Research Group, University of Newcastle) 2014. The Australasian Clinical Indicator Report: 2006-2013. 15th edn. Sydney: ACHS. Viewed 9 April 2018, https://www.achs.org.au/media/88679/clinical_indicator_report_2006_2013.pdf.

WHA (Women's Healthcare Australasia) 2007. Supporting excellence in maternity care: the core maternity indicators project: findings from the core maternity indicators project. Canberra: WHA.

Relational attributes

Related metadata references:

Supersedes National Core Maternity Indicators: PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019