新冠肺炎增加了高收入国家和中等收入国家现有的性别死亡率差距

InternationalJournalofInfectiousDiseases148(2024)107167

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InternationalJournalofInfectiousDiseases

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COVID-19increasedexistinggendermortalitygapsinhigh-incomemorethanmiddle-incomecountries

KathleenBeegle

1,*,

GabrielDemombynes

1,

DamiendeWalque

1,

PaulGubbins

2,

JeremyVeillard

3,#

1WorldBank,Washington,D.C.,USA

2Consultant,Chile

3WorldBank,Colombia

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updates

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abstract

Articlehistory:

Received12April2024Revised27June2024Accepted3July2024

Objective:ToanalyzehowpatternsofexcessmortalityvariedbysexandagegroupsacrosscountriesduringtheCOVID-19pandemicandtheirassociationwithcountryincomelevel.

Methods:WeusedWorldHealthOrganizationexcessmortalityestimatesbysexandagegroupsfor75countriesin2020and62countriesin2021,restrictingthesampletoestimatesbasedonrecordedall-causemortalitydata.Weexaminedpatternsacrosscountriesusingcountry-specificPoissonregressionswithobservationsconsistingofthenumberofexcessdeathsbygroupsdefinedbysexandage.

Findings:Mendieathigherratesinnearlyallplacesandatallagesbeyondage45.In2020,thepan-demicamplifiedthisgendermortalitygapfortheworld,butwithvariationacrosscountriesandbycoun-tryincomelevel.Inhigh-incomecountries,ratesofexcessmortalityweremuchhigherformenthanwomen.Incontrast,inmiddle-incomecountries,thesexratioofexcessmortalitywassimilartothesexratioofexpectedall-causemortality.Theexacerbationofthesexratioofexcessmortalityobservedin2020inhigh-incomecountries,however,declinedin2021.

Conclusion:TheCOVID-19pandemichaskilledmenatmuchhigherratesthanwomen,ashasbeenwelldocumented,butthesegenderdifferenceshavevariedbycountryincome.Thesedifferencesweretheresultofsomecombinationofvariationingenderpatternsofinfectionratesandinfectionfatalityratesacrosscountries.Thegendergapinmortalitydeclinedinhigh-incomecountriesin2021,likelyasaresultofthefasterrolloutofvaccinationagainstCOVID-19.

©2024PublishedbyElsevierLtdonbehalfofInternationalSocietyforInfectiousDiseases.ThisisanopenaccessarticleundertheCCBY-NC-NDIGOlicense

(/licenses/by-nc-nd/3.0/igo/)

Keywords:

CoronavirusPandemic

DevelopingCountriesMortality

Gender

Introduction

Inallcountriesaroundtheworld,womenlivelongerthanmen

[1,2]

.Thereiswell-establishedevidenceofagendermortalitygapdrivenbyarangeofenvironmental,genetic,andculturalfactors

[3]

.Thepersistenceofhighermortalityformenthanwomenhasbeendocumentedwithdatatypicallydrawnprincipallyfromhigh-incomecountries

[4]

.Butthesepatternshavealsobeenshowninlow-incomeregionsoftheworld

[5]

.

*Correspondingauthor:KathleenBeegle,WorldBank,USA.E-mailaddress:

kbeegle@

(K.Beegle).

#Beegleisthecorrespondingauthor.Thefindings,interpretations,andconclu-sionsexpressedinthispaperareentirelythoseoftheauthors.Theydonotnec-essarilyrepresenttheviewsoftheWorldBankanditsaffiliatedorganizations,orthoseoftheExecutiveDirectorsoftheWorldBankorthegovernmentstheyrepre-sent.

Priortothe1950s,disproportionatelyhigherdeathsofmalethanfemaleinfantswerethemaindriverofthelongerlifeex-pectancyofwomen,butmorerecentlytheelevatedmortalityofoldermenhasdriventhegendergapinlifeexpectancy

[6]

.TheCOVID-19pandemicexacerbatedthisgapasage-standardizedex-cessdeathrateswerehigherformenthanwomeninmanycoun-tries

[7,8]

.Thesexinequalityinmortalitygrewinmanyhigh-incomecountriesduetoCOVID-19,thoughintheUS,thisdispar-ityhasbeencharacterizedasmodest,andmortalityfromthepan-demichasnotchangedthe“fundamentaldynamic”ofsexmor-talitygaps

[9]

.Likewise,forEuropeancountries,thedifferenceinmortalitybysexduringtheCOVID-19pandemicissimilartopre-pandemicpatterns

[10]

.Innon-high-incomesettings,bothCOVID-19andexcessdeathage-mortalitycurvesareflatter,onlyinpartduetopopulationstructure

[11]

.Thissuggeststhattheextenttowhichthegendergapinmortalityincreasedlikelydiffersacrosscountryincomelevels.Inpartduetothelackofdata,previous

/10.1016/j.ijid.2024.107167

1201-9712/©2024PublishedbyElsevierLtdonbehalfofInternationalSocietyforInfectiousDiseases.ThisisanopenaccessarticleundertheCCBY-NC-NDIGOlicense

(/licenses/by-nc-nd/3.0/igo/)

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K.Beegle,G.Demombynes,D.deWalqueetal.InternationalJournalofInfectiousDiseases148(2024)107167

detailedanalysisofCOVID-19mortalitypatternsbyagehavecom-binedbothsexes,neglectingthiswell-establishedfactthatmortal-ityratesofmenarehigherthanthatofwomenandthatthismightvarybycountryincomelevel.

Thisstudydrawsonrecentdatathatwerenotavailableforearlierstudiestoexaminetheextenttowhichthegendergapinmortalityshiftedinhigh-andmiddle-incomecountriesduringtheCOVID-19pandemic.Unfortunately,underdevelopedcivilregistra-tionsystemsforreportingonmaleandfemaledeathslimitsdata

availabilityinlow-incomecountries,apersistentlimitationinthe

studyofglobalpopulation-levelmortalitypatterns.

Methods

Datasources

Weusethe“GlobalexcessdeathsassociatedwithCOVID-19(modelledestimates)”dataset(May19,2023update),producedbyWHO’sTechnicalAdvisoryGrouponCOVID-19mortalityassess-ment.Thisdatasetcontainsestimatesofexpectedall-causedeaths,all-causedeaths(actualorpredictedifactualwasnotavailable),andexcessdeathsbyagegroupandsexfor194countriesfor2020and2021.Expectedall-causedeathswereforecastedusinghistoriccountry-levelmonthlymortalitydatapriortothepandemicandserveasreferencepointintheabsenceofCOVID-19.Excessdeathswerecomputedas“themortalityabovewhatwouldbeexpectedbasedonthenon-crisismortalityrateinthepopulationofinterest”bydifferencingactual/predictedall-causedeathsfromexpectedall-causedeaths

[12]

.Thereisextensivedocumentationofthedataandmethodsappliedtogeneratetheseestimates

[13]

.

TheseestimatesarenotofdirectCOVID-19deathsonlybutratherareanestimateofthecombinationofdirectandindirectCOVID-19mortality,asmeasuredbyexcessdeaths.LackingactualmeasuresofdirectandindirectCOVID-19mortalitybysex,werelyonestimatesofexcessdeathsbysex.WecheckthereliabilityofthesedatabycomparingsexmortalityratiosfromtheestimateofexcessdeathsandthosefromreportedCOVID-19deathsforasub-setofcountriesforwhichthisisavailable.Thisratioofratiosisnotalways1.However,thereisnoclearpatternsuggestingthatthera-tiobasedonexcessdeathsisdifferentfromthatconstructedfromreportedCOVID-19mortality(notshownherebutavailableuponrequest).

ThisdatasetalsocontainspopulationcountsfromtheWorldPopulationProspectsbycountry,year,sex,andage

[8]

.Thedatasetcovers194countriesin2020and194in2021.Forthisanalysis,onlycountrieswithexcessdeathestimatesbasedonactualall-causedeath(notpredicted)bysexandagegroupareincluded.Thislimitsthesampleto75countriesin2020and62countriesin2021.Additionally,weexcludecountrieswithtotalexcessdeaths(bothsexescombined)below2000ineither2020or2021.After

applyingthesetwocriteria,wehave66countriesinthisanaly-

sis:54in2020and57in2021

.1

Lastly,weanalyzemortalitydataonlyforadults45yearsandolder,sinceexcessdeathratesareex-tremelylowforyoungerages.

1The66-countrysampleusedfromtheWHOGlobalExcessDeathsdatasetisdividedintothreeincometerciles.Incometercile1(GNIpercapitaPPPrange$5030-$15,530)includesAlbania,Azerbaijan,Bolivia(PlurinationalStateof),Brazil,Colombia,Cuba,Ecuador,Egypt,Georgia,Guatemala,Iran(IslamicRepublicof),Iraq,Kyrgyzstan,RepublicofMoldova,Mongolia,Nicaragua,Peru,Paraguay,SouthAfrica,Tunisia,Ukraine,andUzbekistan.Incometercile2(GNIpercapitaPPPrange$16,090-$33,730)includesArgentina,Bulgaria,BosniaandHerzegovina,Chile,CostaRica,DominicanRepublic,Greece,Croatia,Hungary,Kazakhstan,Latvia,MalaysiaMexico,Oman,Panama,Poland,Romania,RussianFederation,Serbia,Slovakia,Thai-land,andUruguay.Incometercile3(GNIpercapitaPPPrange$36,330-$70,150)includesAustralia,Austria,Belgium,Canada,Switzerland,Czechia,Germany,Spain,Estonia,Finland,France,TheUnitedKingdom,Israel,Italy,Japan,RepublicofKorea,Kuwait,Lithuania,Netherlands,Portugal,Sweden,andUSA.

Characterizingage-mortalitypatterns

Tocharacterizetheage-mortalitypatternsdrawingonthedatafrommultiplecountries,weestimateamodeloftheage-mortalitycurvewithinteractionsbysexforeachcountry.Therearethreereasonsforthismodelingasacomplementtoanalysisofthecoun-trymortalitydatadescribedabove.First,themodelproducesaslopeoftheage-mortalitycurvebysex.Second,itenablestheuseofpredictedvaluesforsomeestimatedquantitieswhichminimizetheinfluenceofoutliers.Andthird,wecanusethemodeltocom-puteconfidenceintervalsforcharacterizationoftheage-sexmor-talitypatternsforthesethreemortalityindicators.

Themodelsareestimatedseparatelyfor2020and2021byfit-tingaPoissonregressionusingdeathsastheresponsevariableandpopulationasanoffset.

Dx,s,i∼Poisson(ux,s,iθi)where

θi=exp(β0,i+β1,i×Male+β2,iAge+β3,i×Age×Male)

wheretheageandsex-specificnumberofdeathsisDx,s,iforthe10-yearagegroupagextoagex+9,x={45,55,65,75,85}forsexs={Male,Female}incountryi.Thex=85datapointscorre-spondtothegroupconsistingofallages85yearsandabove.Tointerpretdeathcountsasmortalityrates(fortheage-sex-specificpopulation),anexposuretermux,s,iwasintroducedasanoffsetinthemodelaslog(ux,s,i).Maleisabinaryvariablewhere1corre-spondstomenand0correspondstowomenandAgeisacontin-uousvariablecenteredatage65.Thecoefficientsexp(β0,i)repre-sentthemortalityrateforfemalesattheageof65years,exp(β1,i)representsthemale-to-femalemortalityrateratioattheageof65,exp(β2,i)representsthemortalityrateratioforfemalesthatdifferby10yearsinage,exp(β2,i+β3,i)representsthemortalityratera-tioformalesthatdifferby10yearsinage.ThePoissonregressionwasfitseparatelywithDx,s,idefinedintermsofexpectedall-causedeathsandwithDx,s,idefinedintermsofestimatedexcessdeathsforbothyears.Forthelatter,whenestimatedexcessdeathswerelessthan0,theywererecodedto0.

Oncetheparametersofeachcountrywereestimatedforex-pectedall-causeandexcessdeathsforbothyears,asimulation-basedinferencewasusedtogaugeuncertaintyaroundpredictedsexratiosofmortalityforeachcountryandagegroup.UsingtheclarifypackageforR,1000setsofcoefficientsweresimulatedfromtheirimplieddistributionafterfittingthemodeltothedata.Foreachcountry,thesesimulatedcoefficientswereusedtogeneratepredictionsofthemortalityrateformalesandfemalesforeachofthefiveagegroups,bycountryandyear.Takingtheratioofthesimulatedpredictedmortalityratesformalesandfemalesyieldedadistributionof1000predictedsexratiosofmortalityforeachagegroupthatcanbeusedforinferenceandgeneratinguncertaintybounds.

Results

Westartwithsomebriefdescriptivesofthedatawehaveavail-able.Themale-to-femaleratioofexpectedall-causemortalitybyagegroup(startingatage45)fornearlyeverycountryin2020isaboveone

(Figure1)

.Theloneexceptionsareamongsttheoldestagegroups(85+)inAlbaniaandBosniaandHerzegovina,alongwithages55-74inKuwait.Inalmostallcountries,thesexratiodeclinesstartingwiththe65-74agegrouporearlier.ThehandfulofcountrieswhichdonotfitthispatternareBolivia,Egypt,Iran,Kuwait,andNicaragua.Therangeonthesexratiogenerallystaysbetween1and2.Insum,amongthecountriesinthissample,atage50,menwerejustovertwiceaslikelytobeexpectedtodiefromallcausesthanwomen,onaverage,in2020.Thepatternof

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K.Beegle,G.Demombynes,D.deWalqueetal.InternationalJournalofInfectiousDiseases148(2024)107167

Figure1.2020Expectedall-causemale-femalemortalityratio.Descriptionoftheillustration:2020Expectedall-causemale-femalemortalitybyagegroup(startingatage

45)andcountry.

thesexratioinmortalitybyagetendstotakeaninverseJ-shape.Theseresultsforall-causemortalityareconsistentwithevidencenotedearlierthatpre-datestheCOVID-19pandemic.

Thepatternofsexratioinexcessdeathsin2020byageisstillfavoringwomen

(Figure2

),butalsoshowsmuchmorevariationacrosscountriesascomparedtoagenerallyconsistentpatternwe

observeinexpectedall-causemortalityin

Figure1.

Thegeneralde-clineormildinverseJ-shapeseenin

Figure1

acrossallcountriesisnolongerpresent.Instead,weobserveawiderangeofdifferingpatterns,insomecasesaJshaperatherthananinverseJshape(suchasinIranandSouthAfrica).Populationsizemayalsofac-torintothewidevariationinpatternsinthesexratioofexcess

4

K.Beegle,G.Demombynes,D.deWalqueetal.InternationalJournalofInfectiousDiseases148(2024)107167

Figure2.2020Excessmale-femalemortalityratio.Descriptionoftheillustration:2020Excessmale-femalemortalityratiobyagegroup(startingatage45)andcountry.

deathssincesmallercountrieshaveworseP-scores(theratioofex-cessdeathstoexpecteddeaths)

[13]

.Overall,thegreatervariationinpatternsinthegenderratioforexcessdeathsascomparedtoexpectedall-causemortalitysuggestscountryvariationinCOVID-19sex-agemortalityrates.Inadditiontothepatternsdiffering,thescaleitselfismuchwider.Whereasbeforetheratiogenerallystayedbetween1and2,wenowhavesomeextremelyhighratios,

andahandfulofvaluesbelow1(andinafewcases,below0).Forexample,theexcessmortalitysexratioformenandwomeninGer-manyages65-74jumpsto30,whereasitisnegativeforGermanadults45-54years.Forboth45-54and55-64yearsolds,thesexratioisnegativeintheDominicanRepublicbutjumpstoover18for75-84and85+agegroups.Partofthisreflectsthesensitivityofratiosforsmallbase-valuecomparisons.Forexample,inHungary,

5

K.Beegle,G.Demombynes,D.deWalqueetal.InternationalJournalofInfectiousDiseases148(2024)107167

Figure3.Predictedmortalitysexratiobyagegroupandcountryincometercile.Descriptionoftheillustration:Predictedmortalitysexratiobyagegroupandcountryincometercile,withuncertaintybars.

theestimateofexcessdeathsforwomen45-54yearsoldis−3.3(effectively0),whereasformenitis126,resultinginaratioof−37.Similarly,intheDominicanRepublic,therewere14estimatedexcessdeathsforwomen85andolder,comparedto256formen,resultinginaratioof19.

DrawingonourPoissonestimates,

Table1

reportstheesti-matesoffourmeasures:femalemortalityatage65,male-femalemortalityratioatage65,andtheageslopeoffemaleandmalemortalityforanadditional10yearsofage.Theseareestimatedfor2020expectedall-causemortality,2020excessmortality,and2021excessmortality.

Table1

showsthepopulation-weightedre-sultsoverallandforeachofthreecountry-incometercilegroupings(population-weighted),aswellaseachcountryresult.

In2020,theaverageratioofmale-to-femalemortalityishigherforexcessdeaths(2.21)thanforexpectedall-causedeaths(1.69)(2020columns2androw1of

Table1

),andthisisalsothecaseforeachofthethreecountry-incometercilegroups.COVID-19am-plifiedthegendermortalitygap,atleastattheagepointof65,in2020.By2021,thesexratioofexcessdeathshasfallen(to1.84)butisstillabovethesexratioforexpectedall-causemortalityin2020(1.69).However,acrossincometercilesthereisvariation.Inthelowestincomegrouping,theexcessmortalitysexratioin2021isslightlylowerthanforexpectedall-cause2020,whereasinthehigh-incomecountries,itremainswellabove(2.23in2021and2.3in2020comparedto1.71forexpectedall-causedeathsin2020).

Theslopeofthecurveofmortalitybyage(thechangeinmortalityassociatedwithanadditional10yearsofage)goesup

sharplyfromexpectedall-causetoexcessdeathsforbothwomen

(from2.95to3.46)andformen(2.49-2.89)in2020.Andthisslopeisgreaterforwomenthanmen,asisexpectedgiventhehighermortalityratesatyoungeragesformeninexcessdeathsin2020.(Thesexratioofmortalityatage65isnecessarilylinkedtotheage-slopeofmortalityforwomenandmen.)Thesepatternsinex-cessmortalityshiftremarkablyby2021.By2021,theageslopeofmortalityshowsmuchlessofagap;itisrelativelysimilarforwomen(2.40)andformen(2.33).Thisshort-livedpatternsug-geststhatCOVID-19maynothavelong-lastingimplicationsforthegendergapinmortalityinhigh-incomecountries,aswasobserved

withthe1918influenzaepidemic(whereaselectioneffectresultedinadecreaseinthegendergapinmortalityinyearsfollowingthatepidemic)

[14]

.But,totheextentthatolderpersondeathswerees-peciallydisplacedinthefirst2yearsofCOVID-19,mortalityrisksmaydeclinemoreforhardesthitgroupsinsubsequentyears

[15]

.

Notably,thispatterninexcessdeathsage-slopesdiffersacrossourcountry-incometercilesin2020.Theageslopeofmortalityishighestforwomeninhigh-incomecountriesfor2020(bothex-pectedall-causedeathsandexcessdeaths),butitfallsdramati-callyby2021whenitisslightlylowerthanthatofmen(2.40forwomenand2.49formen).Ontheotherhand,incountriesinthefirstandsecondterciles,in2021,theageslopeinmortalityre-mainsslightlyhigherforwomen.

Alastpointofnoteisthatfemaleexcessmortalityatage65increasesdramatically(almostdoubles)forcountriesinthefirstandsecondtercilesfrom2020to2021(from447to832forter-cile1countries,andfrom439to824fortercile2countries),whereasitincreasesmuchmoremodestlyfrom2020to2021forthehigh-incomecountriesintercile3(from131to149).Anotherwaytoviewthepatternsbyage,sex,andcountry,istoexaminethemortalitysexratio(M/F)forcountriesbytercileofGNIpercapita,asshownin

Figure3.

Thesefiguresshowthatthewiden-ingofthegendermortalitygapdrivenbyCOVID-19in2020waslimitedtohigher-incomecountriesandprincipallyamongadultsages45-54and55-65.

Figure4

displaysthesamedatawithin-dividualcountrypoints.Thepatternsshowndonotchangesub-stantivelywhenusingthesubsetofcountriesheldconstantacrossyears.

Discussion

Thisarticle,usingaglobaldatasetcoveringawideswathofmiddle-andhigh-incomecountries,confirmspreviousfindings,basedonmorelimiteddata,thatforallagegroupsaboveage45andinallcountrieswithfewexceptions,mendieathigherratesthanwomen.ItalsoidentifiesglobalvariationinpatternsofCOVID-19mortalitybyageandsex.Thefindingscomplementpre-viousfindings

[10]

showingthattheagecurveofexcessdeaths

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K.Beegle,G.Demombynes,D.deWalqueetal.InternationalJournalofInfectiousDiseases148(2024)107167

Table1

Mortalityratesbyage,sex,andcountrydescriptionofthetable:descriptionoftheillustration:Countryregressionestimatesdescribinghowmortalityratesvarybyageandsex.

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K.Beegle,G.Demombynes,D.deWalqueetal.InternationalJournalofInfectiousDiseases148(2024)107167

Figure4.PredictedmortalitysexratiobyagegroupandcountryGNIpercap.Descriptionoftheillustration:PredictedmortalitysexratiowithindividualcountrydatapointsbyagegroupandcountryGNIpercapita,withuncertaintybars.

in2020wasflatterformiddle-incomecountriesandsteeperinwealthiercountries.Thefindingsinthisarticledemonstratethatthisdifferenceisprincipallydrivenbythemortalitypatternsofmen,resultinginCOVID-19amplifyingthegendermortalitygapin2020moreinrichercountriesascomparedtoless-wealthycoun-tries.

Animportantlimitationofthisstudyisthatbecauseitexcludesexcessmortalityestimatesnotbasedonactualobservedmortality,itdoesnotincludeanylow-incomecountries.Suchcountrieshavemortalitypatternsthataredistinctfromthoseinmiddleandhigh-incomeeconomies,notablywell-documenteddifferingchronicandinfectiousdiseasepatternsasmajordriversofmortality.Datashowclustersofcountriesintomortality“convergenceclubs”markedbybothgeographicregionandincomelevel

[16]

.InthecontextofCOVID-19,infectionfatalityratesaresignificantlyhigherinlow-incomecountriesthanhigh-incomesettings

[17]

.Meanwhile,thegendergapinlifeexpectancybetweenwomenandmenwidensascountryincomelevelincreases

[18

],thoughfatalityratesfromCOVID-19arehigherformenthanwomeninlow-incomecoun-triesinAfrica,ashasbeenshowninotherpartsoftheworld

[19]

.Takentogether,thesepointsaresuggestivethattheexac-erbationofthegendergapinhigh-incomerelativetomiddle-incomesettingswouldextendtoacomparisonwithlow-incomecontexts.

Overall,thesefindingspointtotheneedtoconsiderpublicpoliciesduringpublichealthemergenciesthatoffermoretar-getedprotectionforcertaingroups,inthiscase,menover45withco-morbidities,suchasgreatereffortstotargetinterven-tionstothoseworkinginjobsexposingthemtoahigherriskofinfections.

Thepatternsfoundwillhopefullyinspirefuturecountry-levelresearchusingcause-of-deathdatatogetafullerunderstandingofrelevantdriversofage-gendermortalitypatterns,whicharebothbiologicalandsocial.Itisworthwhiletoexplorestructuralsocioe-conomicconditionsthatvarywithcountryincomeandsex,whichwouldalsointeractwithbothinfectionexposureandfatalityrates.Thiswouldinclude,forexample,thestructureofjobsandem-ploymentpatterns(welldocumentedtovarybycountryincomeandsex),especiallytheextentofremoteworkopportunitieswhichmayreduceexposuretoinfectionsduringapandemic.Anotherex-ampleistheextentofresidencyinlong-termcarefacilities.Olderpersons,especiallyolderwomen,havehigherlikelihoodsofresid-inginnursinghomesinwealthiercountriesthanlower-incomesettings.Whenthesefacilitiesareofpoorqualityandsafetytheyresultingreaterexposure

[20]

.Athirdareacouldbethepro-fileofco-morbiditiespre-existinginthepopulation.Forexample,womenarerelativelymoreobesethanmeninlowandmiddle-incomeeconomiesbutnotinhigh-incomecountries

[21]

.Specific

8

K.Beegle,G.Demombynes,D.deWalqueetal.

toCOVID-19,thereisevidencethatwomenaremorelikelytogetdiagnosedthanmeninhigh-incomecontexts

[22

],butthismaybelesslikelyinmiddleandlow-incomesettingswheregendergapsinaccesstohealthcarearearguablygreaterthanforhigh-incomesettings

[20].

Lastly,theanalysisinthisarticleisalsoareminderofthevalueofdemographicdataandthevalueofeffortsbycountrygovern-mentsandinternationalorganizationstopromoteandstandardizevitalstatisticsdata.

Declarationsofcompetinginterest

Theauthorshavenocompetinginterestsorconflictofinteresttodeclare.

Funding

ThisworkwassupportedbytheWorldBankResearchSupportBudget.

Ethicalapproval

Thisworkusespubli