In 2023, Australia's fertility rate reached its lowest ever figure, at fewer than 1.5 children born per women of childbearing age. In general, Australia’s fertility rate has been fairly consistent throughout the past four decades, fluctuating between 1.7 and two births per woman, however the recent drop in fertility may be a result of the Covid-19 pandemic - it remains to be seen what the full extent of the pandemic will be on demographic trends. Population aging in Australia Like most other developed nations, Australia has been experiencing population ageing, driven by declining fertility rate and increased longevity, with an average life expectancy at birth of 83 years in 2020. Amid the pandemic, Australia also witnessed a noticeable decrease in the number of births to approximately 294.4 thousand, the lowest value since 2011. “No kids attached” Childfree couples could become the norm in Australia, as couples living without children are expected to become Australia’s most common family type in a few years’ time. While many families may suffer from involuntary childlessness, other couples would opt for a childfree life for various reasons. Especially in times of COVID-19, couples might not want to risk having children with increasing job insecurity.

BackgroundThe risk of preterm birth (PTB) and low birthweight (LBW) may change over time the longer that immigrants reside in their adopted countries. We aimed to study the influence of acculturation on the risk of these outcomes in Australia.MethodsA retrospective cohort study using linked health data for all non-Indigenous births from 2005–2013 in Western Australia was undertaken. Acculturation was assessed through age on arrival, length of residence, interpreter use and having an Australian-born partner. Adjusted odds ratios (aOR) for term-LBW and PTB (all, spontaneous, medically-indicated) were calculated using multivariable logistic regression in migrants from six ethnicities (white, Asian, Indian, African, Māori, and ‘other’) for different levels of acculturation, compared to the Australian-born population as the reference.ResultsThe least acculturated migrant women, those from non-white non-Māori ethnic backgrounds who immigrated at age ≥18 years, had an overseas-born partner, lived in Australia for < 5 years and used a paid interpreter, had 58% (aOR 1.58, 95% CI 1.15–2.18) higher the risk of term-LBW and 40% (aOR 0.60, 95% CI 0.45–0.80) lower risk of spontaneous PTB compared to the Australian-born women. The most acculturated migrant women, those from non-white non-Māori ethnic backgrounds who immigrated at age 10 years and did not use an interpreter, had similar risk of term-LBW but 43% (aOR 1.43, 95% CI 1.14–1.78) higher risk of spontaneous PTB than the Australian-born women.ConclusionAcculturation is an important factor to consider when providing antenatal care to prevent PTB and LBW in migrants. Acculturation may reduce the risk of term-LBW but, conversely, may increase the risk of spontaneous PTB in migrant women residing in Western Australia. However, the effect may vary by ethnicity and warrants further investigation to fully understand the processes involved.

BackgroundIn recent decades, there has been a shift to later childbearing in high-income countries. There is limited large-scale evidence of the relationship between maternal age and child outcomes beyond the perinatal period. The objective of this study is to quantify a child’s risk of developmental vulnerability at age five, according to their mother’s age at childbirth.Methods and findingsLinkage of population-level perinatal, hospital, and birth registration datasets to data from the Australian Early Development Census (AEDC) and school enrolments in Australia’s most populous state, New South Wales (NSW), enabled us to follow a cohort of 99,530 children from birth to their first year of school in 2009 or 2012. The study outcome was teacher-reported child development on five domains measured by the AEDC, including physical health and well-being, emotional maturity, social competence, language and cognitive skills, and communication skills and general knowledge. Developmental vulnerability was defined as domain scores below the 2009 AEDC 10th percentile cut point.The mean maternal age at childbirth was 29.6 years (standard deviation [SD], 5.7), with 4,382 children (4.4%) born to mothers aged

This dataset presents the percentage of low birthweight babies (less than 2,500 grams) born to women who gave birth aged younger than 20 years, by the mother's usual place of residence. The data spans the year of 2015 and is aggregated to 2015 Department of Health Primary Health Network (PHN) areas, based on the 2011 Australian Statistical Geography Standard (ASGS). The data is sourced from the Australian Institute of Health and Welfare (AIHW) National Perinatal Data Collection (NPDC) and historical data for time trends. Where the term 'teenage mother' is used the analysis is based on women who gave birth aged under 20. Teenage mothers and their babies are more likely to experience broader disadvantage, have antenatal risk factors and have poorer maternal and baby outcomes during and after birth, than older mothers and their babies. The Teenage Mothers in Australia data accompanies the Teenage Mothers in Australia 2015 Report. For further information about this dataset, visit the data source: Australian Institute of Health and Welfare - Teenage Mothers in Australia 2015 Data Tables. Please note: AURIN has spatially enabled the original data using the Department of Health - PHN Areas.

BackgroundThere is growing evidence from high-income countries that maternal country of birth is a risk factor for stillbirth. We aimed to examine the association between maternal region of birth and stillbirth between 2000 and 2011 inclusive in Victoria, Australia.MethodsRetrospective population based cohort study of all singleton births at 24 or more weeks gestational age from 2000–2011 in Victoria, Australia. Stillbirths due to termination of pregnancy, babies with congenital anomalies and Indigenous mothers were excluded. Main Outcome Measure: Stillbirth.ResultsOver the 12-year period there were 685,869 singleton births and 2299 stillbirths, giving an overall stillbirth rate of 3·4 per 1000 births. After adjustment for risk factors, compared to women born in Australia/New Zealand, women born in South Asia (aOR 1.27, 95% CI 1.01–1.53, p = 0.01), were more likely to have a stillbirth whereas women born in South East and East Asia were (aOR 0.60, (95% CI 0.49–0.72, p<0.001) less likely to have a stillbirth. Additionally, the increasing rate of stillbirth as gestation length progressed began to rise earlier and more steeply in the South Asian compared to Australian/New Zealand born women. The following risk factors were also significantly associated with an increased odds of stillbirth in multivariate analyses: maternal age <20 and 35 years and more, nulliparity, low socio-economic status, previous stillbirth, no ultrasound reported in 1st trimester, pre-existing hypertension, antepartum haemorrhage and failure to detect growth restriction antenatally.ConclusionMaternal region of birth is an independent risk factor for stillbirth. Improvements in the rate of stillbirth, particularly late pregnancy stillbirth, are likely to be gained in high-income settings where clinical care is informed by maternal region of birth.

Data have been collected by the Australian and New Zealand Neonatal Network (ANZNN) to improve the care of high-risk newborn infants and their families in Australian and New Zealand through collaborative audit and research. This is the seventeeth year that the ANZNN has collected data, allowing comparative reporting over time.Registration criteria - babies who meet one or more of the following criteria are eligible for registration with the ANZNN:* born at less than 32 weeks gestation, or* weighed less than 1,500 grams at birth, or* received assisted ventilation (mechanical ventilation) including intermittent positive pressure ventilation (IPPV) or continuous positive pressure (CPAP) or high flow for four or more consecutive hours, or died while receiving mechanical ventilation prior to four hours of age, or* received major surgery (surgery that involved opening a body cavity), or* received therapeutic hypothermia.Babies who were discharged home and readmitted to neonatal intensive care unit (NICU) during their neonatal period were not eligible for registration in the ANZNN. The hospital of registration was the first level III NICU in which the baby, aged less than 28 days, stayed for four or more hours. Babies who received their entire care in a level II hospital or who were not transferred to a level III NICU during the first 28 days were registered to the first level II centre that they remained in for four or more hours.In 2011, there were 7,412 babies from 22 level III NICUs in Australia and 1,770 babies from six level III NICUs in New Zealand registered to ANZNN. In 2011, 769 babies fulfilled the ANZNN criteria for registration to 22 level II units in Australia and New Zealand.Data in this collection include:maternal characteristics (maternal age, previous antenatal history, assisted conception, presenting antenatal problem, antenatal corticosteroid use, multiple births, method of birth, place of birth, transport after birth to a level III NICU and breastfeeding at discharge) and baby's characteristics (baby gender, resuscitation in delivery suite, apgar score at birth, admission temperature, indication for respiratory support, exogenous surfactant, type of assisted ventilation, ventilation in babies born at less than 32 weeks gestation, ventilation in babies born at 32 to 36 weeks gestation, ventilation in babies born at term, supplemental oxygen therapy, chronic lung disease, pulmonary air leak, neonatal sepsis, retinopathy of prematurity, intraventricular haemorrhage, late cerebral ultrasound, necrotising enterocolitis, congenital anomalies, transfer from level III NICUs to other units, length of stay until discharge home and survival of the ANZNN registrants).

Length of residence and the odds of stillbirth in migrants from specific ethnic backgrounds compared to the Australian-born population.

Background and Purpose: Cultural and language barriers may affect quality of care, such as adherence to medications. We examined whether adherence to prevention medications within the year after stroke/transient ischemic attack (TIA) differed by region of birth. Methods: An observational study of adults with stroke/TIA admitted to hospitals in the Australian Stroke Clinical Registry (Queensland, Victoria; 2012-2016; n=45 hospitals), with linked administrative data. Region of birth was categorized into 10 groups (Australia, Other Oceania, North-West Europe, Southern/Eastern Europe, North Africa/Middle East, South-East Asia, North-East Asia, Southern/Central Asia, Americas, Sub-Saharan Africa). Analysis was limited to those with a first-ever stroke/TIA who were dispensed an antihypertensive, lipid-lowering, or antithrombotic medication within 1-year post-discharge. Medication adherence was calculated based on the proportion of days covered until 1 year immediately post-discharge/death. Associations between region of birth and being adherent (PDC ≥80%) was determined using multivariable logistic regression (adjusted for age, sex, stroke type, ability to walk on admission, discharge destination, socioeconomic position, main language spoken, comorbidity score). Results: Among 24,236 eligible participants (median age 74 years, 44% female, 68% Australian-born), 54% were adherent to antihypertensive medications, 56% to lipid-lowering medications, and 49% to antithrombotic medications. Compared to Australian-born participants, those born in Other Oceania (4.0%) were less likely to be adherent to lipid-lowering medications (OR 0.78, 95% CI 0.67-0.90) and antithrombotic (OR 0.84, 95% CI 0.72-0.97). Compared to Australian-born participants, those born in Southern and Central Asia (1.4%) were less likely to be adherent to lipid-lowering medications (odds ratio [OR]: 0.76, 95% CI 0.58-0.99) and antithrombotic (0.55, 95% CI 0.40-0.76). No significant differences were found with other regions. Conclusions: Disparities by the region of birth were observed in medication adherence after stroke/TIA for participants born in Asia and Oceania. Targeted education to improve medication adherence, specific to the needs of these groups, is warranted.

The data has been collected by the Australian and New Zealand Neonatal Network (ANZNN) to improve the care of high-risk newborn infants and their families in Australian and New Zealand through collaborative audit and research. This is the fourteenth year that the ANZNN has collected data, allowing comparative reporting over time. Registration criteria - babies who meet one or more of the following criteria are eligible for registration with the ANZNN: * born at less than 32 completed weeks gestation, or * weighed less than 1,500 grams at birth, or * received assisted ventilation (mechanical ventilation) including intermittent positive pressure ventilation (IPPV) or continuous positive pressure (CPAP) for four or more consecutive hours, or died while receiving mechanical ventilation prior to four hours of age, or * received major surgery (surgery that involved opening a body cavity), or * received therapeutic hypothermia. Babies who were discharged home and readmitted to neonatal intensive care unit (NICU) during their neonatal period were not eligible for registration in the ANZNN. Babies who were discharged home and readmitted to a NICUS during their neonatal period are not registered to ANZNN. The hospital of registration for a baby is the first level III NICU that the baby remained in for four or more hours during the first 28 days of life. Babies who received their entire care in a level II hospital or who were not transferred to a level III NICU during the first 28 days were registered to the first level II centre that they remained in for four or more hours. In 2004, 7,399 babies registered to ANZNN in all NICUs in Australia and New Zealand and 361 babies registered to ANZNN in 15 level II nurseries. Data in this collection include: maternal characteristics (maternal age, presenting antenatal problem, antenatal corticosteroid use, method of birth and place of birth) and baby's characteristics (baby gender, transfer after birth, multiple births, congenital abnormalities, apgar score at birth, exogenous surfactant, respiratory assistance, type of assisted ventilation, ventilation in babies born at less than 32 weeks gestation, ventilation in babies born at 32 to 36 weeks gestation, ventilation in babies born at term, chronic lung disease, pulmonary air leak, cerebral ultrasound, neonatal surgery, necrotising enterocolitis, neonatal infection,, transfer from level III NICUs to other units, length of stay until discharge home and survival of the ANZNN registrants). https://npesu.unsw.edu.au/data-collection/australian-new-zealand-neonatal-network-anznn

BackgroundLow birth weight has been consistently associated with adult chronic disease risk. The thrifty phenotype hypothesis assumes that reduced fetal growth impacts some organs more than others. However, it remains unclear how birth weight relates to different body components, such as circumferences, adiposity, body segment lengths and limb proportions. We hypothesized that these components vary in their relationship to birth weight.MethodsWe analysed the relationship between birth weight and detailed anthropometry in 1270 singleton live-born neonates (668 male) from the Mater-University of Queensland Study of Pregnancy (Brisbane, Australia). We tested adjusted anthropometry for correlations with birth weight. We then performed stepwise multiple regression on birth weight of: body lengths, breadths and circumferences; relative limb to neck-rump proportions; or skinfold thicknesses. All analyses were adjusted for sex and gestational age, and used logged data.ResultsCircumferences, especially chest, were most strongly related to birth weight, while segment lengths (neck-rump, thigh, upper arm, and especially lower arm and lower leg) were relatively weakly related to birth weight, and limb lengths relative to neck-rump length showed no relationship. Skinfolds accounted for 36% of birth weight variance, but adjusting for size (neck-rump, thigh and upper arm lengths, and head circumference), this decreased to 10%. There was no evidence that heavier babies had proportionally thicker skinfolds.ConclusionsNeonatal body measurements vary in their association with birth weight: head and chest circumferences showed the strongest associations while limb segment lengths did not relate strongly to birth weight. After adjusting for body size, subcutaneous fatness accounted for a smaller proportion of birth weight variance than previously reported. While heavier babies had absolutely thicker skinfolds, this was proportional to their size. Relative limb to trunk length was unrelated to birth weight, suggesting that limb proportions at birth do not index factors relevant to prenatal life.

Multiple logistic regression results of sociodemographic characteristics and attitudes towards gender roles and IPV index, associated with intimate partner violence (IPV) for Australia-born women and women born in conflict-affected countries at baseline and follow-up: Adjusted odds ratios (aOR) with 95% confidence interval (95% CI).

The data has been collected by the Australian and New Zealand neonatal Network (ANZNN) to improve the care of high-risk newborn infants and their families in Australia and New Zealand through collaborative audit and research. The data were collected from all level III neonatal intensive care units in both Australia and New Zealand, all level II special care units in New Zealand and the special care unit in Tasmania. The data include information on all babies born at less than 32 weeks gestation or with a birthweight of less than 1500 grams and babies who received assisted ventilation or major surgery. In 2006, there were 6,494 mothers in Australia and New Zealand who gave birth to babies who were admitted to a level III or level II nursery. Among babies born in 2006, 7,592 were admitted to a level III NICU in Australia or New Zealand and 411 were admitted to one of the fifteen paricipating level II nurseries in Tasmania and New Zealand. Data in this collection include maternal characteristics (maternal age, gestational age, presenting antenatal problem, antenatal corticosteroid use, method of delivery, place of birth, transfer after birth to a level III NICU, nultiple births and breastfeeding at discharge); and baby's characteristics (baby's gender, admission temperature, apgar score at birth, type of assisted ventilation, exogenous surfactant, chronic lung disease, supplemental oxygen, air leak, retinopathy of prematurity, cerebral ultrasound and intraventricular haemorrhage, necrotising enterocolitis, neonatal surgery, neonatal sepsis, congenital anoamlies, transfer from level IIl NICUs to other nurseries and length of stay until discharge home). https://npesu.unsw.edu.au/data-collection/australian-new-zealand-neonatal-network-anznn

Characteristics of the population of the study.

Absolute numbers, rates, and unadjusted odds ratios of stillbirth for migrants, stratified by acculturative factors, compared with the Australian-born population.

In 2024, the average life expectancy in the world was 71 years for men and 76 years for women. The lowest life expectancies were found in Africa, while Oceania and Europe had the highest. What is life expectancy?Life expectancy is defined as a statistical measure of how long a person may live, based on demographic factors such as gender, current age, and most importantly the year of their birth. The most commonly used measure of life expectancy is life expectancy at birth or at age zero. The calculation is based on the assumption that mortality rates at each age were to remain constant in the future. Life expectancy has changed drastically over time, especially during the past 200 years. In the early 20th century, the average life expectancy at birth in the developed world stood at 31 years. It has grown to an average of 70 and 75 years for males and females respectively, and is expected to keep on growing with advances in medical treatment and living standards continuing. Highest and lowest life expectancy worldwide Life expectancy still varies greatly between different regions and countries of the world. The biggest impact on life expectancy is the quality of public health, medical care, and diet. As of 2022, the countries with the highest life expectancy were Japan, Liechtenstein, Switzerland, and Australia, all at 84–83 years. Most of the countries with the lowest life expectancy are mostly African countries. The ranking was led by the Chad, Nigeria, and Lesotho with 53–54 years.

BackgroundMigrant women, especially from Indian and African ethnicity, have a higher risk of stillbirth than native-born populations in high-income countries. Differential access or timing of ANC and the uptake of other services may play a role. We investigated the pattern of healthcare utilisation among migrant women and its relationship with the risk of stillbirth (SB)—antepartum stillbirth (AnteSB) and intrapartum stillbirth (IntraSB)—in Western Australia (WA).Methods and findingsA retrospective cohort study using de-identified linked data from perinatal, birth, death, hospital, and birth defects registrations through the WA Data Linkage System was undertaken. All (N = 260,997) non-Indigenous births (2005–2013) were included. Logistic regression analysis was used to estimate odds ratios and 95% CI for AnteSB and IntraSB comparing migrant women from white, Asian, Indian, African, Māori, and ‘other’ ethnicities with Australian-born women controlling for risk factors and potential healthcare-related covariates. Of all the births, 66.1% were to Australian-born and 33.9% to migrant women. The mean age (years) was 29.5 among the Australian-born and 30.5 among the migrant mothers. For parity, 42.3% of Australian-born women, 58.2% of Indian women, and 29.3% of African women were nulliparous. Only 5.3% of Māori and 9.2% of African migrants had private health insurance in contrast to 43.1% of Australian-born women. Among Australian-born women, 14% had smoked in pregnancy whereas only 0.7% and 1.9% of migrants from Indian and African backgrounds, respectively, had smoked in pregnancy. The odds of AnteSB was elevated in African (odds ratio [OR] 2.22, 95% CI 1.48–2.13, P < 0.001), Indian (OR 1.64, 95% CI 1.13–2.44, P = 0.013), and other women (OR 1.46, 95% CI 1.07–1.97, P = 0.016) whereas IntraSB was higher in African (OR 5.24, 95% CI 3.22–8.54, P < 0.001) and ‘other’ women (OR 2.18, 95% CI 1.35–3.54, P = 0.002) compared with Australian-born women. When migrants were stratified by timing of first antenatal visit, the odds of AnteSB was exclusively increased in those who commenced ANC later than 14 weeks gestation in women from Indian (OR 2.16, 95% CI 1.18–3.95, P = 0.013), Māori (OR 3.03, 95% CI 1.43–6.45, P = 0.004), and ‘other’ (OR 2.19, 95% CI 1.34–3.58, P = 0.002) ethnicities. With midwife-only intrapartum care, the odds of IntraSB for viable births in African and ‘other’ migrants (combined) were more than 3 times that of Australian-born women (OR 3.43, 95% CI 1.28–9.19, P = 0.014); however, with multidisciplinary intrapartum care, the odds were similar to that of Australian-born group (OR 1.34, 95% CI 0.30–5.98, P = 0.695). Compared with Australian-born women, migrant women who utilised interpreter services had a lower risk of SB (OR 0.51, 95% CI 0.27–0.96, P = 0.035); those who did not utilise interpreters had a higher risk of SB (OR 1.20, 95% CI 1.07–1.35, P < 0.001). Covariates partially available in the data set comprised the main limitation of the study.ConclusionLate commencement of ANC, underutilisation of interpreter services, and midwife-only intrapartum care are associated with increased risk of SB in migrant women. Education to improve early engagement with ANC, better uptake of interpreter services, and the provision of multidisciplinary-team intrapartum care to women specifically from African and ‘other’ backgrounds may reduce the risk of SB in migrants.

Among countries with the highest number of overseas Chinese on each continent, the largest Chinese diaspora community is living in Indonesia, numbering more than ten million people. Most of these people are descendants from migrants born in China, who have moved to Indonesia a long time ago. On the contrary, a large part of overseas Chinese living in Canada and Australia have arrived in these countries only during the last two decades. China as an emigration country Many Chinese people have emigrated from their home country in search of better living conditions and educational chances. The increasing number of Chinese emigrants has benefited from loosened migration policies. On the one hand, the attitude of the Chinese government towards emigration has changed significantly. Overseas Chinese are considered to be strong supporters for the overall strength of Chinese culture and international influence. On the other hand, migration policies in the United States and Canada are changing with time, expanding migration opportunities for non-European immigrants. As a result, China has become one of the world’s largest emigration countries as well as the country with the highest outflows of high net worth individuals. However, the mass emigration is causing a severe loss of homegrown talents and assets. The problem of talent and wealth outflow has raised pressing questions to the Chinese government, and a solution to this issue is yet to be determined. Popular destinations among Chinese emigrants Over the last decades, English speaking developed countries have been popular destinations for Chinese emigrants. In 2022 alone, the number of people from China naturalized as U.S. citizens had amounted to over 27,000 people, while nearly 68,000 had obtained legal permanent resident status as “green card” recipients. Among other popular immigration destinations for Chinese riches are Canada, Australia, Europe, and Singapore.

BackgroundLiterature focusing on migration and maternal health inequalities is inconclusive, possibly because of the heterogeneous definitions and settings studied. We aimed to synthesize the literature comparing the risks of severe maternal outcomes in high-income countries between migrant and native-born women, overall and by host country and region of birth.Methods and findingsSystematic literature review and meta-analysis using the Medline/PubMed, Embase, and Cochrane Library databases for the period from January 1, 1990 to April 18, 2023. We included observational studies comparing the risk of maternal mortality or all-cause or cause-specific severe maternal morbidity in high-income countries between migrant women, defined by birth outside the host country, and native-born women; used the Newcastle–Ottawa scale tool to assess risk of bias; and performed random-effects meta-analyses. Subgroup analyses were planned by host country and region of birth.The initial 2,290 unique references produced 35 studies published as 39 reports covering Europe, Australia, the United States of America, and Canada. In Europe, migrant women had a higher risk of maternal mortality than native-born women (pooled risk ratio [RR], 1.34; 95% confidence interval [CI], 1.14, 1.58; p < 0.001), but not in the USA or Australia. Some subgroups of migrant women, including those born in sub-Saharan Africa (pooled RR, 2.91; 95% CI, 2.03, 4.15; p < 0.001), Latin America and the Caribbean (pooled RR, 2.77; 95% CI, 1.43, 5.35; p = 0.002), and Asia (pooled RR, 1.57, 95% CI, 1.09, 2.26; p = 0.01) were at higher risk of maternal mortality than native-born women, but not those born in Europe or in the Middle East and North Africa. Although they were studied less often and with heterogeneous definitions of outcomes, patterns for all-cause severe maternal morbidity and maternal intensive care unit admission were similar. We were unable to take into account other social factors that might interact with migrant status to determine maternal health because many of these data were unavailable.ConclusionsIn this systematic review of the existing literature applying a single definition of “migrant” women, we found that the differential risk of severe maternal outcomes in migrant versus native-born women in high-income countries varied by host country and region of origin. These data highlight the need to further explore the mechanisms underlying these inequities.Trial RegistrationPROSPERO CRD42021224193.

Abstract

The Programme for International Student Assessment (PISA) is a triennial international survey which aims to evaluate education systems worldwide by testing the skills and knowledge of 15-year-old students.

As in previous cycles, the 2015 assessment covers science, reading and mathematics, with the major focus in this cycle on scientific literacy. Financial literacy is an optional assessment, as it was in 2012. A questionnaire about students' background is distributed to all participating students. Students may also choose to complete additional questionnaires: one about their future studies/career, a second about their familiarity with information and communication technologies. School principals complete a questionnaire about the learning environment in their schools, and parents of students who sit the PISA test can choose to complete a questionnaire about the home environment. Seventy-two countries and economies, including all 35 OECD countries, participated in the PISA 2015 assessment.

Geographic coverage

PISA 2015 covered 72 counteies (35 OECD countries and 37 partner countries and economies. All countries attempted to maximise the coverage of 15-year-olds enrolled in education in their national samples, including students enrolled in special educational institutions.

Analysis unit

To better compare student performance internationally, PISA targets a specific age of students. PISA students are aged between 15 years 3 months and 16 years 2 months at the time of the assessment, and have completed at least 6 years of formal schooling. They can be enrolled in any type of institution, participate in full-time or part-time education, in academic or vocational programmes, and attend public or private schools or foreign schools within the country. Using this age across countries and over time allows PISA to compare consistently the knowledge and skills of individuals born in the same year who are still in school at age 15, despite the diversity of their education histories in and outside of school.

Universe

To provide valid estimates of student achievement, the sample of students had to be selected using established and professionally recognised principles of scientific sampling in a way that ensured representation of the full target population of 15-year-old students in the participating countries. Furthermore, quality standards had to be maintained with respect to (i) the coverage of the PISA international target population, (ii) accuracy and precision, and (iii) the school and student response rates.

National Project Managers (NPMs) might have found it necessary to reduce their coverage of the target population by excluding, for instance, a small, remote geographical region due to inaccessibility, or a language group, possibly due to political, organisational or operational reasons, or special education needs students. Areas deemed to be part of a country (for the purpose of PISA), but which were not included for sampling, although this occurred infrequently, were designated as non-covered areas. Care was taken in this regard because, when such situations did occur, the national desired target population differed from the international desired target population. In an international survey in education, the types of exclusion must be defined consistently for all participating countries and the exclusion rates have to be limited. Indeed, if a significant proportion of students were excluded, this would mean that survey results would not be representative of the entire national school system. Thus, efforts were made to ensure that exclusions, if they were necessary, were minimised according to the PISA 2015 Technical Standards (see Appendix F of the Technical Report).

Kind of data

Sample survey data [ssd]

Sampling procedure

In all but one country, the Russian Federation, the sampling design used for the PISA assessment was a two-stage stratified sample design. The first-stage sampling units consisted of individual schools having 15-year-old students, or the possibility of having such students at the time of assessment. Schools were sampled systematically from a comprehensive national list of all PISA-eligible schools, known as the school sampling frame, with probabilities that were proportional to a measure of size. The measure of size was a function of the estimated number of PISA-eligible 15-year-old students enrolled in the school. This is referred to as systematic probability proportional to size (PPS) sampling. Prior to sampling, schools in the sampling frame were assigned to mutually exclusive groups based on school characteristics called explicit strata, formed to improve the precision of sample-based estimates. The second-stage sampling units in countries using the two-stage design were students within sampled schools. Once schools were selected to be in the sample, a complete list of each sampled school's 15-year-old students was prepared. Each country had to set a target cluster size (TCS) of 42 students for computer-based countries and 35 for paper-based countries, although with agreement countries could use alternative values. The sample size within schools is prescribed, within limits, in the PISA Technical Standards (see Annex F of the Technical Report). From each list of students that contained more than the target cluster size, a sample of around 42 students were selected with equal probability and for lists with fewer than the target number, all students on the list were selected.

Mode of data collection

Face-to-face [f2f]

Research instrument

Paper-based tests were used, with assessments lasting two hours. In a range of countries and economies, an additional 40 minutes were devoted to the computer-based assessment of mathematics, reading and problem solving.

Test items were a mixture of questions requiring students to construct their own responses and multiple-choice items. The items were organised in groups based on a passage setting out a real-life situation. A total of about 390 minutes of test items were covered, with different students taking different combinations of test items.

Students answered a background questionnaire, which took 30 minutes to complete, that sought information about themselves, their homes and their school and learning experiences. School principals were given a questionnaire, to complete in 30 minutes, that covered the school system and the learning environment. In some countries and economies, optional questionnaires were distributed to parents, who were asked to provide information on their perceptions of and involvement in their child’s school, their support for learning in the home, and their child’s career expectations, particularly in mathematics. Countries could choose two other optional questionnaires for students: one asked students about their familiarity with and use of information and communication technologies, and the second sought information about their education to date, including any interruptions in their schooling and whether and how they are preparing for a future career.

The PISA 2015 Science Test Questions are available in 90 other languages.

Cleaning operations

Software specially designed for PISA facilitated data entry, detected common errors during data entry, and facilitated the process of data cleaning. Training sessions familiarised National Project Managers with these procedures.

Response rate

A response rate of 85% was required for initially-selected schools. If the initial school response rate fell between 65% and 85%, an acceptable school response rate could still be reached through the use of replacement schools.

An overall response rate of 80% of selected students in participating schools was required. A student who had participated in the original or follow-up cognitive sessions was considered to be a participant. A minimum student response rate of 50% within each school was required for a school to be regarded as participating: the overall student response rate was computed using only students from schools with at least a 50% student response rate. Again, weighted student response rates were used for assessing this standard.

Life expectancy in Australia was just below 35 in the year 1870, and over the course of the next 150 years, it is expected to have increased to 83.2 by the year 2020. Although life expectancy has generally increased throughout Australia's history, there were several times where the rate deviated from its previous trajectory. the most noticeable changes were between 1890 and 1920. This period included Australia's Independence movement, the implementation of the 'White Australia' policy, the First World War and Spanish Flu epidemic, all of which impacted the demographics of Australia.