Matthew Gray|Diana Smart
Growing Up in Australia: The Longitudinal Study of Australian Children: A Valuable New Data Source for Economists
Australian Institute of Family Studies|Australian Government|Australian Institute of Family Studies|Australian Bureau of Statistics
long history economic research issues affecting children families children areas equivalence scales engel 1895 poverty rowntree 1901 fertility population growth example malthus 1826 adam smith 1776 p 213 discussing colonies north america provided early statement importance investments early childhood children tender years infancy well fed properly taken care grown value labour greatly overpays maintenance arrived maturity high price labour low price land enable establish manner fathers 1960s 1970s interest economic issues related children families children grew rapidly expansions areas human capital development becker 1965 female labour supply killingsworth 1983 internal family dynamics manser brown 1980 recently economists using longitudinal studies child development address range economic questions particularly questions intersection economics developmental psychology example hill et al 2005 waldfogel 2006 also work undertaken economics investment early childhood carneiro heckman 2003 release data second wave growing australia longitudinal study australian children lsac australia joins organisation economic cooperation development countries nationally representative longitudinal study child development1 advent lsac analysis issues australian children families limited lack suitable data prior lsac australian longitudinal studies childrens development usually focused narrow range outcomes healthfocused nationally representative samples relatively small sample sizes generally limited information collected factors parental labour force status economic position households children live2 perspective economist studies often limited use used addressing specific questions lsac aims shed light development current generation australian children investigate contribution childrens social economic cultural environments adjustment wellbeing specifically seeks improve understanding complex interplay factors foster impede healthy early childhood development identify opportunities early intervention prevention policy areas concerning children families inform policy debate general study enables examination impact childrens early experiences later development mapping diverse pathways children follow develop also provides opportunity identify longterm consequences policy children family survey collects information multiple facets childrens development health wellbeing including physical health social cognitive emotional development study seeks understand risks protective processes underlying childrens development looking interaction childrens psychological physical attributes temperament health contexts children raised particularly family child care school neighbourhood community experiences study also examines dynamics within settings example parenting practices quality coparental relationships children exposed quality care received differing types nonparental care lsac initiated funded department families housing community services indigenous affairs fahcsia australian government study managed partnership australian institute family studies aifs australian bureau statistics abs consortium leading researchers experts universities research agencies provides advice design methodology issues wave 1 field work conducted iview field work wave 2 onward undertaken abs funding four biennial waves initially provided first wave conducted 2004 funding subsequently extended provide four biennial survey waves review seeks provide overview lsac highlight features data likely particular interest economists lsac following two cohorts children 14 years possibly longer starting children aged 01 year 45 years 01 year old cohort often described b baby cohort 45 year old cohort k kindergarten cohort alternatively identified years birth 19992000 birth cohort 20032004 birth cohort facetoface interviews conducted every 2 years first wave data collection occurring 2004 march november wave 2 field work commenced april 2006 completed early 2007 wave 3 field work commenced april 2008 completed early 2009 twocohort design enable information childrens development first 18 years life collected 14 years two cohorts also compared overlapping ages gauge effect growing differing social conditions policy settings overlapping cohorts occurred first time completion wave 3 ages 45 67 years continue occur subsequent wave 2004 study recruited nationally representative sample 5107 infants 4983 children aged 45 years selected medicare australia enrolment database sampling unit child twostage clustered design employed first selecting postcodes children allowing analysis children within community reducing overall cost study children cohorts selected postcodes 40 children per postcode usually invited participate study larger states usually 20 children per postcode smaller states territories stratification used ensure proportional geographical representation states territories capital city statistical division method postcode selection took account number children postcode hence potential participants study australiawide approximately equal chance selection one 25 information sampling provided soloff et al 2006 sample broadly representative australian children citizens permanent residents two selected age cohorts children born march 2003 february 2004 b cohort children born march 1999 february 2000 k cohort children remote parts australia excluded extremely high data collection costs areas reports multiple participants sought order obtain information childs behaviour across differing contexts reduce effects respondent bias information collected child using physical measurement cognitive testing interviewing depending upon age child parents live child biological adoptive stepparents homebased centrebased carers preschool children regularly nonparental care teachers schoolaged children wave 2 information also sought parents live apart child still contact child lsac terminology parent living elsewhere table 1 provides summary sources information lsac facetoface interviews conducted primary carer child parent 1 wave 1 childs biological mother 97 per cent families addition parent 1 asked complete questionnaire time use diary childs activities resident parent biological adoptive stepparent also asked complete leavebehind questionnaire consent sought send selfcompleted questionnaire homebased carers centrebased carers teachers almost parents provided consent addition interviewer recorded observations neighbourhood family child wave 1 b cohort physical measurements child taken weight head circumference k cohort physical measurement cognitive testing carried waves 2 3 height weight waist measurements taken cohorts ageappropriate cognitive testing continued wave 3 b cohort cognitive testing repeated wave 1 k cohort assessments age 67 years onwards child interviewed although focus lsac study child structured child unit observation lsac also used conduct analysis parents study child outlined lsac collects data wide range topics information collected family demographics including education ethnicity religion detailed information study childs physical mental health learning cognition social emotional outcomes collected children develop affected experiences child care school quality learning environment information collected aspects study childs life quite detailed labour market information collected parents income living standards family child lives novel feature lsac provision time use diaries collect data childs activities throughout two 24 hour periods divided 15 minute blocks summary topics covered lsac scope provided table 2 final wave 1 sample represented 53 per cent families sent letter medicare australia refusals largest source sample loss 31 per cent b cohort 35 per cent k cohort followed noncontact noncontact occurred address details outofdate post office box address available rates noncontact 10 per cent b cohort 14 per cent k cohort response rates achieved noncontactable families excluded 64 per cent b cohort 57 per cent k cohort3 wave 2 data collection took place 2006 march november 9070 families completing interview 4606 b cohort 4464 k cohort yielding response rate 90 per cent originally recruited sample similar numbers families cohort participated wave 3 data collection took place 2008 response rate wave 3 86 per cent originally recruited samples yielding total 8711 participants 4381 b cohort 4330 k cohort end wave 3 data collection period 460 families withdrawn permanently study 256 families elected participate third wave remained members study ninetythree families away entire fieldwork period six children died since start study remainder families could contacted thus largest cause nonresponse inability locate families families still considered study members4 retention rate compares favourably achieved comparable international studies example millennium cohort study longitudinal study approximately 19 000 families babies united kingdom sample retention rate 79 per cent waves 1 2 similar time period lsac sweep 1 2 terminology used millennium cohort study hansen joshi 2007 lsac sample broadly representative population although differences census data abs relation several family characteristics wave 1 thus children mothers fathers completed year 12 overrepresented sample cohorts differences 810 percentage points infants siblings underrepresented 3 percentage points 45 year olds couple families overrepresented soleparent families underrepresented 4 percentage points mothers speak language english home underrepresented cohorts 2 percentage points aifs 2008 provides detailed comparison lsac data census data weights provided data reduce impact biases sample selection process survey nonresponses clustered stratified nature sampling needs taken account using data issues discussed detail soloff et al 2006 wave 2 lsac variation participation rates selected subgroups singleparent families 81 per cent took part 80 per cent aboriginal torres strait islander families 85 per cent families mother spoke english second language 87 per cent families mother completed year 12 higher nonparticipation rate subgroups primarily related difficulties making contact families rather refusal participate families respond part study exception facetoface interview parent 1 families must complete order participate wave table 3 shows response rates waves 1 2 differing data collection components well main data collection waves betweenwave mailed selfcompleted surveys conducted aim surveys gain update childs progress specific areas familys experiences well maintain engagement studys families date waves 15 25 conducted wave 15 collected information childrens health development well family educational care experiences b cohort information collected families service utilisation parental employment history maternity leave arrangements wave 25 collected information work child care labour force status child support childrens media technology use wave 35 occur mid2009 betweenwave mailed surveys lower response rate main waves wave 15 resulted 7167 useable responses responded wave 1 response rate 72 per cent wave 25 resulted 6498 useable responses response rate families interviewed wave 2 72 per cent although forms also received 20 per cent families participated wave 2 contact information data several administrative databases linked lsac medicare australia database obtain information childs medical service use immunisation history national childcare accreditation council data obtain information child care centres attended children data census population housing abs socioeconomic demographic profiles neighbourhoods communities children live also linked lsac data study proceeds hoped data sources linked lsac example new national literacy numeracy assessments geospatial data sources lsac dataset publicly available subject application process granting deed licence data user training workshops held regularly assist users gain familiarity complex dataset data waves 1 15 2 25 released anticipated data wave 3 released towards end 2009 information accessing data user training provided aifs 2009 one strengths lsac wide variety areas childrens lives data collected well family allows interrelationships many different aspects child development family life analysed examples issues interest economists lsac provide insight include intergenerational linkages parents children duncan brooksgunn 1997 ermisch francesconi 2001 particular value lsac addressing question provides information childrens family educational child care experiences economic circumstances child young extent living disadvantaged neighbourhood impacts upon outcomes children family question great deal international research example kling liebman katz 2007 leventhal brooksgunn 2000 little australian research occurrence changes family structure fertility separation divorce repartnering impacts changes short longerterm economic wellbeing children family members well developmental trajectories maternal paternal family labour supply decisions impacts different patterns labour force participation childrens developmental outcomes well family relationships functioning broadly active area research internationally yet analysed detail using australian data economics investment early childhood investment childrens human capital impacts upon development cognitive noncognitive skills child support impact childrens wellbeing economic position family impact adverse events example drought unemployment relationship breakdown ill health death family member housing stress wellbeing parents children degree impacts vary children families different backgrounds although lsac still young already used analyse economic issues examples included illustrate ways data used leigh gong 2009 used lsac estimate cognitive gaps indigenous nonindigenous young australians bradbury 2007 analysed relationships child outcomes family socioeconomic characteristics impact neighbourhood disadvantage childrens outcomes analysed edwards 2005 edwards bromfield 2009 data also used analyse range labour market issues patterns return work following childbirth impact maternity leave focus several papers articles whitehouse diamond baird 2007 whitehouse et al 2007 baxter 2008 baxter gray 2008 articles paper analysed labour market participation mothers fathers young children links wellbeing baxter et al 2007 baxter alexander 2008 gray baxter 2008 renda baxter alexander 2009 end 2009 researchers access three waves data plus additional two betweenwave mailed survey data value survey increase additional waves data collected lsac data offer exciting possibilities economic research begun explored