Academic Edi o : Hee-Young Choi
Recei ed: 14 Janua y 2025
Re ised: 5 Feb ua y 2025
Accep ed: 10 Feb ua y 2025
Published: 12 Feb ua y 2025
Ci a ion: Gha bi, M.E.; Guisasola, L.;
Galdón, A.; Vinuela-Na a o, V.;
Pé ez-Co al, J.; Tomás, N.; Vila-Vidal,
N. Ocula Biome y Dis ibu ion and
One-Yea G ow h in Eigh -Yea -Old
Sou he n Eu opean Schoolchild en
Unde he CISViT P ojec . Child en
2025,12, 221. h ps://doi.o g/
10.3390/child en12020221
Copy igh : © 2025 by he au ho s.
Licensee MDPI, Basel, Swi ze land.
This a icle is an open access a icle
dis ibu ed unde he e ms and
condi ions o he C ea i e Commons
A ibu ion (CC BY) license
(h ps://c ea i ecommons.o g/
licenses/by/4.0/).
A icle
Ocula Biome y Dis ibu ion and One-Yea G ow h in
Eigh -Yea -Old Sou he n Eu opean Schoolchild en Unde he
CISViT P ojec
Ma iam El Gha bi 1,2,* , Lau a Guisasola 1, Alba Galdón 1, Vallde lo s Vinuela-Na a o 1,2 ,
Joan Pé ez-Co al 1,2 , Nú ia Tomás 1and Nú ia Vila-Vidal 1,2
1Visió Op ome ia i Salu , Depa amen d’Òp ica i Op ome ia, Uni e si a Poli ècnica de Ca alunya,
08222 Te assa, Spain; [email p o ec ed] (L.G.); [email p o ec ed] (A.G.);
[email p o ec ed] (V.V.-N.); [email p o ec ed] (J.P.-C.); [email p o ec ed] (N.T.);
[email p o ec ed] (N.V.-V.)
2Cen e Uni e si a i de la Visió, Uni e si a Poli ècnica de Ca alunya, 08222 Te assa, Spain
*Co espondence: [email p o ec ed]
Abs ac : Objec i e: To analyse a ia ions in axial leng h (AL), co neal adius (CR) and
he AL/CR a io o e one yea in eigh -yea -old schoolchild en, conside ing sex, e hnici y
and e ac i e e o . Me hods: Vision sc eenings we e conduc ed in 16 schools in Te assa
(Ba celona, Spain) wi h eigh -yea -old child en as pa o he CISViT p ojec . Measu emen s
included ocula biome ics (AL and CR) and non-cycloplegic au o e ac ion o e ac i e
e o . Pa en al ques ionnai es p o ided demog aphic da a (bi h da e, e hnici y). The same
p ocedu es we e epea ed a e one yea . Resul s: Ocula biome ic pa ame e s di e ed by
sex and e hnici y. Boys and child en o Magh eb descen had longe AL and la e CR han
gi ls and Caucasian child en (p< 0.001 o bo h isi s). The AL/CR a io was highe in boys
han gi ls (p= 0.002 in he ini ial isi and p= 0.011 in he ollow-up isi ) bu consis en
ac oss e hnici ies (p= 0.291 and p= 0.390). AL and AL/CR a io di e ed signi ican ly by
e ac i e e o s a us (p< 0.001 in bo h isi s), inc easing in mo e myopic child en, while
CR showed no signi ican di e ence. In myopic child en, he AL/CR a io exceeded 3.0,
and ypical sex-based biome ic di e ences diminished. G ow h a es o AL and AL/CR
a io we e simila ac oss sex and e hnici y, indica ing minimal demog aphic in luence.
Conclusions: AL and CR di e signi ican ly by sex and e hnici y, wi h demog aphic
di e ences e iden in baseline measu emen s bu no in g ow h a es o e one yea . The
consis ency o he AL/CR a io ac oss e hnici ies, despi e sex-based di e ences, suppo s
i s u ili y as a eliable me ic o assessing e ac i e de elopmen in di e se popula ions.
Keywo ds: axial leng h; co neal adius; ocula biome y; myopia; Sou he n Eu ope;
schoolchild en
1. In oduc ion
Myopia has eme ged as a global public heal h conce n in ecen decades, signi ican ly
a ec ing a la ge po ion o he popula ion, pa icula ly school-aged child en [
1
–
6
]. Ea ly
onse o myopia is linked o he de elopmen o high myopia (
≥−
6 D) in adul hood, which
inc eases he isk o e inal and op ic ne e pa hologies, po en ially leading o se e e isual
impai men o blindness [
1
,
7
]. Myopia and i s associa ed complica ions a e one o he
leading causes o isual impai men and blindness wo ldwide [8,9].
Gi en he inc easing p e alence and po en ial complica ions o myopia, i is c ucial
o ha e e ec i e me hods o iden i y child en a isk o de eloping o inc easing myopia.
Child en 2025,12, 221 h ps://doi.o g/10.3390/child en12020221
Child en 2025,12, 221 2 o 16
Ocula biome y measu emen s, which p o ide de ailed da a on axial leng h (AL) and
co neal cu a u e adius (CR), as well as he a io be ween hem (AL/CR), a e impo an
indica o s o he p e en ion and managemen o childhood myopia [10–12].
S udies ha e shown ha he CR unde goes signi ican a ia ions du ing he i s h ee
o i e yea s o li e and s abilises he ea e [
13
,
14
]. In con as , AL expe iences signi ican
g ow h un il adolescence [10–12,14]. The myopic changes in e ac i e e o a e ela ed o
he excessi e g ow h o AL, esul ing in a misma ch wi h CR and o he ocula biome ic
pa ame e s. The e o e, al hough he myopic changes in e ac i e e o a e mainly ela ed
o he excessi e g ow h o AL, analysing he AL alue alone is no su icien o iden i y
child en a isk o de eloping myopia; i is necessa y o conside bo h i s g ow h a e and
i s ela ionship wi h CR. The AL/CR a io can se e as an impo an indica o o he onse
and p og ession o myopia [12,14].
Longi udinal coho s udies o AL a e mo e impo an han c oss-sec ional s udies o
iden i ying child en a isk o myopia because hey allow he moni o ing o changes o e
ime wi hin he same indi iduals, p o iding a dynamic unde s anding o eye g ow h and
myopia p og ession. These s udies be e p edic u u e e ac i e changes, e alua e he
e ec i eness o myopia con ol ea men s, enhance he unde s anding o he mechanisms
behind myopia de elopmen and p og ession and examine co ela ions be ween AL and
o he ocula pa ame e s, o e ing a comp ehensi e iew ha c oss-sec ional s udies canno
cap u e. This long- e m p edic i e capaci y is c ucial o pedia ic e ac i e de elopmen
and suppo s he c ea ion o p ac ical ools, such as online myopia p og ession o myopia
isk calcula o s, which can help ansla e esea ch indings in o clinical p ac ice. Such
ools b idge he gap be ween empi ical da a and eal-wo ld applica ions, aiding clinicians
in explaining po en ial myopia p og ession o pa en s and guiding pe sonalized myopia
managemen s a egies.
The AL de elopmen is in luenced by a ious demog aphical ac o s, wi h age, sex,
e hnici y and an h opome y being he mos signi ican [
10
,
14
–
18
]. Geog aphical egion
o esidence is also a c i ical a iable, as he e a e no able di e ences in bo h he alue
and g ow h a es o AL be ween Eu opean and Asian popula ions, especially in school-
aged child en [
10
,
12
]. While nume ous coho s udies ha e been conduc ed on Asian
and No he n Eu opean popula ions, esea ch in Sou he n Eu ope emains spa se. So,
conside ing he impac o en i onmen al and cul u al ac o s on myopia de elopmen ,
s udies in di e se popula ions a e c ucial.
The Te assa Visual Heal h Child en’s Coho (CISViT) p ojec is a pionee ing
schoolchild en coho s udy in he Sou he n Eu opean popula ion. Wi h da a collec ed om
he CISViT p ojec , his s udy aims o analyse a ia ions in AL, CR and he a io AL/CR
o e a one-yea pe iod in eigh -yea -old schoolchild en, aking in o accoun sex, e hnici y
and e ac i e e o . By doing so, i seeks o p o ide aluable insigh s in o egional di e -
ences in ocula biome ic g ow h pa e ns and hei implica ions o myopia p e en ion
and managemen .
2. Ma e ials and Me hods
2.1. S udy Design
As pa o he CISViT p ojec , which in ol es 16 schools in he ci y o Te assa
(Ba celona, Spain), his p ospec i e longi udinal epidemiological coho s udy consis s o
wo phases. The ini ial da a collec ion phase in ol es a isual sc eening o eigh -yea -old
schoolchild en a he Cen e Uni e si a i de la Visió (Uni e si y Vision Cen e ; he Uni-
e si a Poli ècnica de Ca alunya op ome y clinic) comp ising monocula measu emen s
o dis ance isual acui y in bo h eyes using Snellen cha s, non-cycloplegic objec i e e-
ac ion measu emen s by WAM 5500 open- ield au o e ac o (G and Seiko Co., Tokyo,
Child en 2025,12, 221 3 o 16
Japan) and ocula biome ic measu emen s, including AL and CR, by MYAH biome e
(Topcon Heal hca e Co., Tokyo, Japan). Addi ionally, a dis ance and nea co e es was
conduc ed o de ec binocula ision misalignmen s. In he ollow-up phase, a isual
sc eening was conduc ed one yea la e wi hin he school p emises consis ing o monocula
non-cycloplegic objec i e e ac ion measu emen s in bo h eyes (ARK-1e au o e ac o ,
Nidek Co., Gamago i, Japan) and ocula biome ic measu emen s, including AL and CR,
by AL-SCAN M biome e (Nidek Co., Japan).
Fo logis ic easons, pa icipan s we e sc eened using di e en au o e ac ome e s and
biome e s in he ini ial and ollow-up phases. This should no esul in signi ican di e -
ences in ou comes, as a p e ious s udy [
19
] has demons a ed minimal di e ences be ween
open- ield au o e ac ome e s wi hou ogging, such as he WAM 5500, and closed- ield au-
o e ac ome e s wi h ogging, like he Nidek ARK-1e. In cases o luc ua ing measu emen s
o disc epancies wi h isual acui y, e inoscopy was pe o med as an addi ional e i ica ion
me hod. On he o he hand, a compa a i e s udy be ween he wo biome e s used in he
CISViT p ojec [
20
] con i med ha hey bo h p o ide ep oducible and in e changeable
da a, showing a wi hin-subjec s anda d de ia ion o 0.01 mm and a epea abili y limi o
0.04 mm, ensu ing consis ency and eliabili y ac oss he s udy phases. In addi ion o hese
es s, be o e each isual sc eening, he pa icipan s’ pa en s we e equi ed o comple e
a de ailed ques ionnai e, which collec ed, among o he in o ma ion, e hnic ances y and
bi h da a.
2.2. E hics S a emen
This s udy was app o ed by he D ugs Medica ion E hics Commi ee (CEIm) o Mú ua
Te assa (P/22-090) and designed in acco dance wi h he Decla a ion o Helsinki.
W i en in o med consen was ob ained om each pa en o gua dian p io o he
schoolchild en’s in ol emen in he s udy, ensu ing ha hey ully unde s ood he na u e
and pu pose o he esea ch. In o med consen was equi ed and e-con i med a he
ollow-up isi .
2.3. S udy Popula ion Sample
The s udy in ol ed 476 eigh -yea -old schoolchild en en olled in p ima y schools in
Te assa. A sample size calcula ion conduc ed wi h EpiDa a so wa e (EpiDa a Associa ion,
Ve sion 4.2) de e mined ha a minimum o 435 pa icipan s was needed, assuming a 95%
con idence le el.
Applying he inclusion c i e ia o as igma isms equal o o less han 1.50 D and
anisome opia no exceeding 1.50 D, he e ac i e e o o he sample, measu ed in e ms
o sphe ical equi alen (SE), anged om +3.00 o −4.25 D.
To ensu e he alidi y and eliabili y o he esul s, speci ic exclusion c i e ia we e
applied. Child en unde going any myopia con ol ea men s we e excluded o a oid
con ounding e ec s on ocula de elopmen . Addi ionally, child en wi h amblyopia o
s abismus we e excluded, as hese condi ions could in e e e wi h ypical eye de elopmen .
Pa icipan s we e also excluded i hey showed low coope a ion du ing sc eening o i hey
did no pa icipa e in he ollow-up phase o he s udy.
2.4. Measu emen s and Va iable De ini ions
•Sociodemog aphic Va iables
The sociodemog aphic a iables conside ed we e sex and e hnici y. The sample
was classi ied by e hnici y in o Caucasian, Magh eb and La in, as hese we e he mos
ep esen a i e, and he ca ego y o O he , which included schoolchild en o sub-Saha an
A ican, Asian and bi acial descen .
Child en 2025,12, 221 4 o 16
•Ocula Biome ic Va iables
The biome ic a iables conside ed we e AL, CR and he AL/CR a io. The CR was
calcula ed as he a e age o he wo p incipal co neal adii (Equa ion (1)). The a io AL/CR
was de ined as he quo ien o hese wo a iables (Equa ion (2)).
RC =R1 +R2
2(1)
AL/CR a io =AL
CR (2)
•Re ac i e E o
To analyse e ac i e e o , SE was used, de ined as Equa ion (3).
SE =Sphe e +Cylind e(−)
2(3)
The classi ica ion o SE was based on e ac i e s a us. Hype opia was de ined as
SE g ea e han +0.50 D, emme opia as SE be ween +0.50 D and
−
0.50 D (inclusi e) and
myopia as SE less han
−
0.50 D. Rega ding SE p og ession, changes be ween he ini ial and
ollow-up isi s we e ca ego ized as less han o equal o
−
0.50 D o mo e nega i e han
−0.50 D.
2.5. S a is ical Analysis
The Kolmogo o –Smi no no mali y es was employed o assess he no mal dis i-
bu ion o a iables. The AL and CR pa ame e s ollowed a no mal dis ibu ion (p> 0.05),
while SE and he AL/CR a io did no ollow a no mal dis ibu ion (p< 0.001). Gi en
he high co ela ion be ween measu emen s om bo h eyes o AL (Pea son’s : 0.908,
p< 0.001), CR (Pea son’s : 0.948, p< 0.001), AL/CR a io (Spea man’s ho: 0.925, p< 0.001)
and SE (Spea man’s ho: 0.882, p< 0.001), only da a om he igh eye was included o he
s a is ical analysis.
To assess di e ences among he sample g oups, an independen - es o ANOVA
was used o a iables wi h a pa ame ic dis ibu ion, while he Mann–Whi ney U es
o K uskal–Wallis es we e applied o non-pa ame ic a iables. Pos hoc analysis was
pe o med o iden i y speci ic g oup di e ences. All analyses we e ca ied ou using SPSS
so wa e ( e sion 29.0.2.0), wi h s a is ical signi icance se a p< 0.05.
3. Resul s
3.1. Sample Popula ion Cha ac e is ics
This s udy included 478 schoolchild en who me he inclusion c i e ia. A e excluding
wo pa icipan s due o he inabili y o measu e e ac i e e o du ing he ollow-up
isi , he inal sample size was 476 schoolchild en. A he ini ial isi he mean age was
8.2
±
0.5 yea s, which inc eased o 9.3
±
0.5 yea s a he one-yea ollow-up isi . The s udy
sample bene i ed om a wide e hnic di e si y gi en ha i comp ised child en o Sou he n
Eu opean descen as well as a subs an ial p opo ion o child en o Magh eb descen , a
popula ion ha has no been p e iously s udied. Table 1de ails he popula ion sample
demog aphic cha ac e is ics including sex, e hnici y and e ac i e e o , and Figu e 1
shows myopia p e alence ound o he di e en demog aphic cha ac e is ics conside ed
a he ini ial isi .
Child en 2025,12, 221 5 o 16
Table 1. Dis ibu ion o e ac i e e o g oups and e hnici y in he s udy sample a he ini ial isi ,
ca ego ised by sex. p- alues indica e di e ences by sex.
All
N = 476
Boys
N = 231
(48.5%)
Gi ls
N = 245
(51.5%)
p
Re ac i e E o
Hype opic 90 (18.9%) 43 (18.6%) 47 (19.2%) 0.673
Emme opic 340 (71.4%) 164 (71.0%) 176 (71.8%) 0.515
Myopic 46 (9.7%) 24 (10.4%) 22 (9.0%) 0.768
E hnici y
Caucasian 214 (45%) 106 (45.9%) 108 (44.1%) 0.891
Magh eb 141 (29.6%) 69 (29.9%) 72 (29.4%) 0.801
La in 79 (16.6%) 38 (16.5%) 41 (16.7%) 0.736
O he 42 (8.8%) 18 (7.8) 24 (9.8%) 0.355
Child en 2025, 12, x FOR PEER REVIEW 5 o 16
Table 1. Dis ibu ion o e ac i e e o g oups and e hnici y in he s udy sample a he ini ial isi ,
ca ego ised by sex. p- alues indica e diffe ences by sex.
All
N = 476
Boys
N = 231 (48.5%)
Gi ls
N = 245 (51.5%) P
Re ac i e E o
Hype opic 90 (18.9%) 43 (18.6%) 47 (19.2%) 0.673
Emme opic 340 (71.4%) 164 (71.0%) 176 (71.8%) 0.515
Myopic 46 (9.7%) 24 (10.4%) 22 (9.0%) 0.768
E hnici y
Caucasian 214 (45%) 106 (45.9%) 108 (44.1%) 0.891
Magh eb 141 (29.6%) 69 (29.9%) 72 (29.4%) 0.801
La in 79 (16.6%) 38 (16.5%) 41 (16.7%) 0.736
O he 42 (8.8%) 18 (7.8) 24 (9.8%) 0.355
Figu e 1. Myopia p e alence a he ini ial isi , ca ego ised by sex and e hnici y.
3.2. Gene al Ocula Biome ic Pa ame e Dis ibu ion
Table 2 shows he dis ibu ion o ocula biome ic pa ame e s ound a he ini ial isi
and he one-yea ollow-up. Signi ican diffe ences we e obse ed be ween boys and gi ls
ac oss all ocula biome ic pa ame e s in bo h he ini ial and ollow-up isi s. Boys exhib-
i ed a longe AL (p < 0.001 in bo h isi s), a la e CR (p < 0.001 in bo h isi s) and a highe
AL/CR a io (p = 0.002 in he ini ial isi and p = 0.011 in he ollow-up isi ) compa ed o
gi ls.
Table 2. Ocula biome ic pa ame e dis ibu ion ca ego ised by sex a he ini ial and he one-yea
ollow-up isi s. p- alues indica e diffe ences be ween boys and gi ls.
Ini ial Visi (8.2 Yea s Old) Follow-Up Visi (9.3 Yea s Old)
All Boys Gi ls p All Boys Gi ls p
AL (mm) 22.93 ± 0.78 23.22 ± 0.73 22.65 ± 0.72 <0.001 23.06 ± 0.81 23.35 ± 0.75 22.79 ± 0.77 <0.001
CR (mm) 7.79 ± 0.27 7.86 ± 0.27 7.72 ± 0.25 <0.001 7.78 ± 0.27 7.85 ± 0.28 7.71 ± 0.25 <0.001
AL/CR 2.95 ± 0.08 2.96 ± 0.09 2.93 ± 0.08 0.002 2.97 ± 0.09 2.98 ± 0.09 2.96 ± 0.08 0.011
Figu e 1. Myopia p e alence a he ini ial isi , ca ego ised by sex and e hnici y.
3.2. Gene al Ocula Biome ic Pa ame e Dis ibu ion
Table 2shows he dis ibu ion o ocula biome ic pa ame e s ound a he ini ial
isi and he one-yea ollow-up. Signi ican di e ences we e obse ed be ween boys and
gi ls ac oss all ocula biome ic pa ame e s in bo h he ini ial and ollow-up isi s. Boys
exhibi ed a longe AL (p< 0.001 in bo h isi s), a la e CR (p< 0.001 in bo h isi s) and
a highe AL/CR a io (p= 0.002 in he ini ial isi and p= 0.011 in he ollow-up isi )
compa ed o gi ls.
Table 2. Ocula biome ic pa ame e dis ibu ion ca ego ised by sex a he ini ial and he one-yea
ollow-up isi s. p- alues indica e di e ences be ween boys and gi ls.
Ini ial Visi (8.2 Yea s Old) Follow-Up Visi (9.3 Yea s Old)
All Boys Gi ls pAll Boys Gi ls p
AL (mm)
22.93
±
0.78 23.22
±
0.73 22.65
±
0.72
<0.001
23.06
±
0.81 23.35
±
0.75 22.79
±
0.77
<0.001
CR (mm)
7.79
±
0.27 7.86
±
0.27 7.72
±
0.25
<0.001
7.78
±
0.27 7.85
±
0.28 7.71
±
0.25
<0.001
AL/CR
2.95
±
0.08 2.96
±
0.09 2.93
±
0.08
0.002
2.97
±
0.09 2.98
±
0.09 2.96
±
0.08
0.011
Child en 2025,12, 221 6 o 16
3.3. Ocula Biome ic Pa ame e s by Re ac i e E o
As shown in Table 3, AL alues di e ed signi ican ly among he e ac i e g oups
(p< 0.001 in bo h he ini ial and ollow-up isi s). As expec ed, a g ea e AL was associa ed
wi h myopic e ac i e e o . Pos hoc analyses e ealed signi ican di e ences in AL
(p< 0.001 in bo h isi s) ac oss all h ee e ac i e g oups. In con as , no di e ences in
CR we e obse ed ac oss e ac i e g oups (p= 0.069 in he ini ial isi and 0.149 in he
ollow-up isi ).
Table 3. Ocula biome ic pa ame e dis ibu ion ca ego ised by sex and e ac i e e o a bo h
he ini ial and one-yea ollow-up isi s. p(sex) indica es di e ences be ween boys and gi ls and p
( e ac i e e o ) indica es di e ences among e ac i e e o g oups.
Ini ial Visi (8.2 Yea s Old) Follow-Up Visi (9.3 Yea s Old)
All Boys Gi ls p(Sex)
p
(Re ac i e
E o )
All Boys Gi ls p(Sex)
p
(Re ac i e
E o )
AL (mm) <0.001 <0.001
All
22.93
±
0.78 23.22
±
0.73 22.65
±
0.72
<0.001
23.06
±
0.81 23.35
±
0.75 22.79
±
0.77
<0.001
Hype opic
22.47
±
0.68 22.75
±
0.65 22.21
±
0.60
<0.001
22.59
±
0.68 22.88
±
0.65 22.32
±
0.61
<0.001
Emme opic
22.97
±
0.74 23.29
±
0.69 22.68
±
0.67
<0.001
23.10
±
0.76 23.40
±
0.70
22.82 ±070 <0.001
Myopic
23.47
±
0.68 23.62
±
0.76 23.29
±
0.83
0.169
23.64
±
0.92 23.77
±
0.85 23.50
±
0.99
0.332
CR (mm) 0.069 0.149
All 7.79 ±0.27 7.86 ±0.27 7.72 ±0.25 <0.001 7.78 ±0.27 7.85 ±0.28 7.71 ±0.25 <0.001
Hype opic 7.75 ±0.23 7.81 ±0.24 7.69 ±0.22 0.0017 7.74 ±0.23 7.80 ±0.24 7.69 ±0.22 0.022
Emme opic 7.81 ±0.28 7.88 ±0.28 7.73 ±0.26 <0.001 7.79 ±0.29 7.88 ±0.29 7.71 ±0.26 <0.001
Myopic 7.73 ±0.23 7.76 ±0.19 7.71 ±0.27 0.512 7.73 ±0.23 7.74 ±0.20 7.71 ±0.27 0.670
AL/CR <0.001 <0.001
All 2.95 ±0.08 2.96 ±0.09 2.93 ±0.08 0.002 2.97 ±0.09 2.98 ±0.09 2.96 ±0.08 0.011
Hype opic 2.90 ±0.07 2.92 ±0.07 2.89 ±0.06 0.044 2.92 ±0.07 2.93 ±0.07 2.90 ±0.06 0.016
Emme opic 2.94 ±0.07 2.96 ±0.08 2.93 ±0.07 0.024 2.97 ±0.07 2.97 ±0.07 2.96 ±0.07 0.127
Myopic 3.04 ±0.10 3.05 ±0.11 3.02 ±0.10 0.612 3.06 ±0.12 3.07 ±0.12 3.05 ±0.11 0.660
The e ac i e g oups also exhibi ed s a is ically signi ican di e ences in he AL/CR
a io (p< 0.001 in bo h isi s), wi h highe a ios in g oups wi h mo e myopic SE, p ima -
ily due o di e ences in AL. No ably, he myopic g oup displayed AL/CR a io alues
exceeding 3.0 a bo h isi s.
When analysing he dis ibu ion o ocula biome y ac oss e ac i e g oups s a i ied
by sex, signi ican di e ences we e obse ed in he hype opic and emme opic g oups only
(Table 3). Boys exhibi ed a longe AL and a la e CR compa ed o gi ls in bo h isi s. A
he ini ial isi , he AL/CR a io was highe in hype opic and emme opic boys compa ed
o gi ls. Howe e , a he ollow-up isi , while his di e ence pe sis ed in he hype opic
g oup, no di e ences we e ound be ween emme opic boys and gi ls. Con e sely, no
di e ences by sex we e iden i ied in he myopic g oup o any biome ic pa ame e a
any isi .
3.4. Co ela ion Be ween Ocula Biome ic Pa ame e s and Re ac i e E o
A signi ican posi i e co ela ion was obse ed be ween AL and CR (Pea son coe -
icien 0.676, p< 0.001), indica ing ha subjec s wi h a longe AL end o ha e a la e
CR. As shown in Table 4, SE was in e sely co ela ed wi h bo h AL and he AL/CR a io,
sugges ing ha hese a iables we e highe in indi iduals wi h mo e nega i e SE. AL was
no co ela ed wi h SE in hype opes, and he signi ican co ela ion was s onge in myopes
han in emme opes. The co ela ion coe icien was highe o he AL/CR a io han o
AL alone. No co ela ion was obse ed be ween CR and SE in any o he e ac i e g oups.
Child en 2025,12, 221 7 o 16
Table 4. Spea man’s ho co ela ion coe icien (p- alue) o ocula biome ic pa ame e s and SE a
he ini ial and ollow-up isi s.
Ini ial Visi (8.2 Yea s Old) Follow-Up Visi (9.3 Yea s Old)
AL CR AL/CR AL CR AL/CR
All −
0.396 (p< 0.001)
−0.018 (p= 0.694) −
0.410 (p< 0.001)
−
0.312 (p< 0.001)
0.072 (p= 0.117) −
0.413 (p< 0.001)
Hype opic −0.204 (p= 0.054) 0.104 (p= 0.330) −
0.384 (p< 0.001)
−0.014 (p= 0.893) 0.196 (p= 0.064) −
0.301 (p= 0.004)
Emme opic −
0.234 (p< 0.001)
−0.011 (p= 0.840) −
0.233 (p< 0.001)
−
0.229 (p< 0.001)
0.037 (p= 0.501) −
0.289 (p< 0.001)
Myopic −
0.603 (p< 0.001)
0.081 (p= 0.593) −
0.682 (p< 0.001)
−
0.661 (p< 0.001)
0.137 (p= 0.365) −
0.767 (p< 0.001)
3.5. Ocula Biome ic Pa ame e s by E hnici y
As shown in Table 5, signi ican di e ences we e ound in AL (p= 0.002 in he ini ial
isi and p< 0.001 in he ollow-up) and CR (p= 0.030 in he ini ial isi and p= 0.018 in
he ollow-up) among he e hnic g oups. Pos hoc analysis iden i ied ha hese di e ences
we e p ima ily be ween Caucasians and Magh eb (p< 0.001), wi h Magh eb displaying
a longe AL and la e CR. In con as , he AL/CR a io dis ibu ion was simila ac oss
e hnic g oups (p= 0.291 in he ini ial isi and 0.390 in he ollow-up).
Table 5. Ocula biome ic pa ame e dis ibu ion ca ego ised by sex and e hnici y a he ini ial and
one-yea ollow-up isi s. p(sex) alues indica e di e ences be ween boys and gi ls and p(e hnici y)
indica e he di e ences among e hnic g oups.
Ini ial Visi (8.2 Yea s Old) Follow-Up Visi (9.3 Yea s Old)
All Boys Gi ls p(Sex) p
(E hnici y) All Boys Gi ls p(Sex) p
(E hnici y)
AL (mm) 0.002 <0.001
Caucasian
22.78
±
0.76 23.09
±
0.69 22.48
±
0.70
<0.001
22.91
±
0.78 23.20
±
0.70 22.61
±
0.73
<0.001
Magh eb
23.10
±
0.81 23.38
±
0.79 22.84
±
0.74
<0.001
23.25
±
0.86 23.52
±
0.82 23.00
±
0.82
<0.001
La in
23.00
±
0.74 23.24
±
0.73 22.77
±
0.68
0.004
23.12
±
0.76 23.36
±
0.76 22.91
±
0.67
0.008
O he
22.93
±
0.78 23.37
±
0.57 22.60
±
0.70
<0.001
23.07
±
0.75 23.53
±
0.53 22.73
±
0.72
<0.001
CR (mm) 0.030 0.018
Caucasian
7.75
±
0.27 7.83
±
0.28 7.68
±
0.24
<0.001
7.74
±
0.27 7.82
±
0.28 7.66
±
0.24
<0.001
Magh eb
7.84
±
0.28 7.89
±
0.28 7.80
±
0.26
0.057
7.84
±
0.28 7.88
±
0.28 7.79
±
0.26
0.060
La in
7.78
±
0.25 7.85
±
0.25 7.72
±
0.68
0.020
7.77
±
0.26 7.84
±
0.26 7.71
±
0.25
0.028
O he
7.79
±
0.27 7.93
±
0.19 7.70
±
0.25
0.002
7.78
±
0.27 7.92
±
0.21 7.67
±
0.25
0.001
AL/CR 0.291 0.390
Caucasian
2.94
±
0.07 2.95
±
0.08 2.93
±
0.06
0.062
2.96
±
0.08 2.97
±
0.08 2.95
±
0.07
0.025
Magh eb
2.95
±
0.09 2.97
±
0.09 2.93
±
0.09
0.029
2.97
±
0.10 2.99
±
0.10 2.95
±
0.10
0.031
La in
2.96
±
0.09 2.96
±
0.09 2.95
±
0.09
0.575
2.98
±
0.09 2.98
±
0.10 2.97
±
0.09
0.623
O he
2.94
±
0.07 2.95
±
0.06 2.94
±
0.068
0.550
2.97
±
0.08 2.97
±
0.08 2.97
±
0.07
0.848
Rega ding sex, boys had a longe AL (p< 0.001 in bo h isi s) han gi ls ac oss all
e hnic g oups. Boys also had a signi ican ly la e CR in mos o he e hnic g oups, excep
in Magh eb whe e he di e ences in CR be ween boys and gi ls is minimal and wi hou
s a is ical signi icance. Caucasian and Magh eb boys showed highe alues in AL/CR a io
han gi ls; no signi ican di e ences in he AL/CR a io by sex we e ound in La in and
o he e hnici ies.
3.6. Ocula Biome ic Pa ame e s Compa ed Ac oss E hnici ies
When compa ing ou esul s wi h indings om o he popula ions [
6
,
10
] (Table 6),
i is obse ed ha he AL in Sou he n Eu ope is lowe han in No he n Eu ope (The
Ne he lands) [10], while he CR is e y simila . On he o he hand, he esul s ob ained in
he Magh eb popula ion closely esembled hose in Eas Asia (China) [
6
]. Non-di e ences
we e obse ed in he AL/CR a io be ween all e hnici ies.
Child en 2025,12, 221 8 o 16
Table 6. Compa ison o ocula biome ic pa ame e s and e ac i e e o among nine-yea -old
schoolchild en ac oss di e en e hnic o igins and s udies: Sou he n Eu opean (CISViT s udy), No h-
e n Eu opean (Gene a ion R s udy) [
10
], Magh eb (CISViT s udy) and Eas Asian (Baoshan Eye
s udy) [
6
]. The SE was ob ained ia cycloplegic au o e ac ion in he Gene a ion R and Baoshan
Eye s udies.
Popula ion G oup AL (mm) CR (mm)
AL/CR Ra io
SE (D) S udy
Sou he n Eu ope 22.91 ±0.78 7.74 ±0.27 2.96 ±0.08 +0.09 ±0.78 CISViT
No he n Eu ope 23.10 ±0.84 7.78 ±0.26 2.97 ±0.09 +0.74 ±1.30
Gene a ion R [
10
]
Magh eb 23.25 ±0.86 7.84 ±0.28 2.97 ±0.10 −0.39 ±1.12 CISViT
Eas Asia 23.29 ±0.87 7.84 ±0.25 2.97 ±0.10 0.02 ±1.29 Baoshan Eye [6]
3.7. Annual G ow h in Ocula Biome ic Pa ame e s
Table 7shows he one-yea g ow h o he ocula biome ic pa ame e s. Signi ican
g ow h in AL (p= 0.010) and AL/CR a io (p< 0.001) was obse ed o e he ollow-up
yea , while CR emained cons an (p= 0.574). This sugges s ha he signi ican AL/CR
a io a ia ion was p ima ily due o AL g ow h.
Table 7. One-yea a ia ion in AL and AL/CR a io o he sample ca ego ised by sex, e ac i e e o
and e hnici y. p( a ia ion) indica es signi icance in he one-yea a ia ion and p(g oups) indica es
di e ences among sexes, e ac i e e o and e hnici y.
AL (mm) AL/CR
Va ia ion p(Va ia ion) p(G oup) Va ia ion p(Va ia ion) p(G oup)
All 0.13 0.010 0.021 <0.001
Sex 0.372 0.863
Boys 0.12 0.072 0.019 0.021
Gi ls 0.14 0.037 0.023 0.002
Re ac i e e o 0.484 0.332
Hype opic 0.12 0.223 0.016 0.116
Emme opic 0.13 0.024 0.022 <0.001
Myopic 0.17 0.336 0.024 0.312
SE a ia ion <0.001 <0.001
∆SE ≥ −0.50 D 0.12 0.034 0.020 0.001
∆SE < −0.50 D 0.17 0.144 0.024 0.038
E hnici y 0.667 0.851
Caucasian 0.12 0.110 0.021 0.004
Magh eb 0.15 0.135 0.021 0.071
La in 0.13 0.286 0.019 0.181
O he 0.14 0.390 0.024 0.127
Al hough no signi ican sex di e ences we e ound in AL g ow h (p= 0.372)
(
Figu e 2A
), gi ls exhibi ed a s a is ically signi ican a ia ion in AL g ow h (p= 0.037),
whe eas boys did no (p= 0.072). No di e ences by sex we e obse ed in CR (0.296) and
AL/CR a io (p= 0.863) a ia ion. Conside ing e hnici y, he e we e no di e ences in he
AL g ow h (p= 0.667) (Figu e 2B), CR (p= 0.436) and he AL/CR a io (p= 0.851) among
he di e en e hnic g oups.
When analysing e ac i e e o , signi ican a ia ion was obse ed only in he em-
me opic g oup, despi e he absence o s a is ically signi ican di e ences in AL (Figu e 2C)
and AL/CR a io a ia ions ac oss e ac i e e o g oups. Clinically, he myopic g oup
exhibi ed g ea e a ia ion bu was no s a is ically signi ican .
Child en 2025,12, 221 9 o 16
Child en 2025, 12, x FOR PEER REVIEW 9 o 16
Figu e 2. One-yea axial leng h g ow h (Δ mm) ca ego ised as ollows: (A) by sex, (B) by e hnici y,
(C) by e ac i e e o g oups.
When analysing e ac i e e o , signi ican a ia ion was obse ed only in he em-
me opic g oup, despi e he absence o s a is ically signi ican diffe ences in AL (Figu e
2C) and AL/CR a io a ia ions ac oss e ac i e e o g oups. Clinically, he myopic
g oup exhibi ed g ea e a ia ion bu was no s a is ically signi ican .
On he o he hand, we analysed he a ia ion in SE o iden i y which g oups wi hin
he s a i ied sample—classi ied by sex, e hnici y and e ac i e e o —showed he g ea -
es a iabili y. As expec ed, he g oup showing a SE a ia ion mo e nega i e han −0.50 D
exhibi ed g ea e AL g ow h (Table 7).
Figu e 3 illus a es he pe cen age o schoolchild en exhibi ing a SE a ia ion mo e
nega i e han −0.50 D du ing he one-yea ollow-up, wi h da a s a i ied by sex, e hnici y
and e ac i e e o . No signi ican diffe ences we e obse ed in e ac i e e o a ia ions
be ween sexes o e hnici ies. Howe e , i is impo an o emphasize ha his nega i e SE
shi was mos p onounced among child en ini ially classi ied as hype opic, indica ing a
highe isk o myopia p og ession in his e ac i e g oup compa ed o emme opic and
myopic child en.
Figu e 2. One-yea axial leng h g ow h (
∆
mm) ca ego ised as ollows: (A) by sex, (B) by e hnici y,
(C) by e ac i e e o g oups.
On he o he hand, we analysed he a ia ion in SE o iden i y which g oups wi hin
he s a i ied sample—classi ied by sex, e hnici y and e ac i e e o —showed he g ea es
a iabili y. As expec ed, he g oup showing a SE a ia ion mo e nega i e han
−
0.50 D
exhibi ed g ea e AL g ow h (Table 7).
Figu e 3illus a es he pe cen age o schoolchild en exhibi ing a SE a ia ion mo e
nega i e han
−
0.50 D du ing he one-yea ollow-up, wi h da a s a i ied by sex, e hnici y
and e ac i e e o . No signi ican di e ences we e obse ed in e ac i e e o a ia ions
be ween sexes o e hnici ies. Howe e , i is impo an o emphasize ha his nega i e SE
shi was mos p onounced among child en ini ially classi ied as hype opic, indica ing a
highe isk o myopia p og ession in his e ac i e g oup compa ed o emme opic and
myopic child en.
In he g oup wi h a SE a ia ion mo e nega i e han
−
0.50 D, he SE a ia ion was
−
0.80 D in hype opes and
−
1.01 D in myopes. This end was e lec ed in axial leng h (AL)
g ow h, wi h hype opes showing a mean inc ease o 0.12 mm compa ed o 0.17 mm in
myopes (Table 7and Figu e 2C).
Child en 2025,12, 221 16 o 16
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He, X.; Zou, H.; Lu, L. Axial leng h/co neal adius a io: Associa ion wi h e ac i e s a e and ole on myopia de ec ion combined
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Ip, J.M.; Huynh, S.C.; Ki ley, A. Va ia ion o he con ibu ion om axial leng h and o he oculome ic pa ame e s o e ac ion by
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Liu, S.; Chen, J.; Wang, J.; Zhu, Z.; Zhang, J.; Zhang, B.; Yang, J.; Du, L.; Zhu, J.; Zou, H.; e al. Cu o alues o axial leng h/co neal
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Disclaime /Publishe ’s No e: The s a emen s, opinions and da a con ained in all publica ions a e solely hose o he indi idual
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