BioMed Central
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International Breastfeeding Journal
Open Access
Research
Reliability of the Hazelbaker Assessment Tool for Lingual Frenulum
Function
Lisa H Amir*
1,2
, Jennifer P James
2
and Susan M Donath
3
Address:
1
Key Centre for Women's Health in Society, University of Melbourne, Australia,
2
Breastfeeding Education and Support Services, The Royal
Women's Hospital, Melbourne, Australia and
3
Clinical Epidemiology and Biostatistics Unit, Murdoch Children's Research Institute, Royal
Children's Hospital, Melbourne, Australia
Email: Lisa H Amir* - lamir@unimelb.edu.au; Jennifer P James - jenni.james@rwh.org.au; Susan M Donath - susan.donath@mcri.edu.au
* Corresponding author
Abstract
Background: About 3% of infants are born with a tongue-tie which may lead to breastfeeding
problems such as ineffective latch, painful attachment or poor weight gain. The Hazelbaker
Assessment Tool for Lingual Frenulum Function (HATLFF) has been developed to give a
quantitative assessment of the tongue-tie and recommendation about frenotomy (release of the
frenulum). The aim of this study was to assess the inter-rater reliability of the HATLFF.
Methods: Fifty-eight infants referred to the Breastfeeding Education and Support Services (BESS)
at The Royal Women's Hospital for assessment of tongue-tie and 25 control infants were assessed
by two clinicians independently.
Results: The Appearance items received kappas between about 0.4 to 0.6, which represents
"moderate" reliability. The first three Function items (lateralization, lift and extension of tongue)
had kappa values over 0.65 which indicates "substantial" agreement. The four Function items
relating to infant sucking (spread, cupping, peristalsis and snapback) received low kappa values with
insignificant p values. There was 96% agreement between the two assessors on the
recommendation for frenotomy (kappa 0.92, excellent agreement). The study found that the
Function Score can be more simply assessed using only the first three function items (ie not scoring
the sucking items), with a cut-off of ≤4 for recommendation of frenotomy.
Conclusion: We found that the HATLFF has a high reliability in a study of infants with tongue-tie
and control infants
Background
About 3% of infants are born with a tongue-tie or partial
ankyloglossia [1]. The Academy of Breastfeeding Medicine
Protocol defines partial ankyloglossia as "the presence of
a sublingual frenulum which changes the appearance
and/or function of the infant's tongue because of its
decreased length, lack of elasticity or attachment too distal
beneath the tongue or too close to or onto the gingival
ridge" [[2] p1]. Complete ankyloglossia in which there is
extensive fusion of the tongue to the floor of the mouth is
extremely rare.
Since the early 1990s, a number of case studies and case
series of infants with tongue-tie experiencing feeding
problems, such as ineffective latch, painful attachment
and poor weight gain, have been published in the breast-
Published: 09 March 2006
International Breastfeeding Journal2006, 1:3 doi:10.1186/1746-4358-1-3
Received: 06 September 2005
Accepted: 09 March 2006
This article is available from: http://www.internationalbreastfeedingjournal.com/content/1/1/3
© 2006Amir et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0
),
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
International Breastfeeding Journal 2006, 1:3 http://www.internationalbreastfeedingjournal.com/content/1/1/3
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feeding literature [3-6]. Many of the case studies/series
report an improved ability to breastfeed following a sim-
ple release of the frenulum (frenotomy) [7]. In infants
aged up to about three months, clinicians have found that
it is safe to release the frenulum with a small pair of sterile
scissors when the infant having difficulty breastfeeding is
found to have a tight frenulum comprised of a thin mem-
brane [7]. Our practice has been to release the frenulum in
infants if there is a significant tongue-tie and there is evi-
dence of difficulty breastfeeding such as slow rate of milk
transfer or ongoing nipple pain or trauma.
A range of clinicians perform this simple frenotomy: den-
tists, surgeons, paediatricians, obstetricians, general prac-
titioners and ear, nose and throat specialists [3,7]. In some
settings, infant feeding specialists are also performing fre-
notomies after appropriate training [8,9], however this
does raise "legal and ethical issues about the scope of lac-
tation consultant practice" which varies around the world
[10] p413].
Our review of 35 infants following tongue-tie release
found a high level of parental satisfaction and no compli-
cations [11]. Some of the parents reported that they appre-
ciated the careful examination of the infant's mouth
during the assessment procedure. For example one parent
stated "Very pleased with assessment" [11] p245].
Correct attachment to the breast involves the infant mov-
ing the tongue forward to grasp and draw the nipple and
surrounding breast tissue well into the mouth to form a
teat [12,13]. Some infants with tongue-tie are unable to
grasp the nipple/breast, while others attach poorly caus-
ing nipple pain or damage [2]. The aetiology of breast-
feeding difficulties in these infants has not been
elucidated, however, ultrasound studies may provide
some evidence in the future. A preliminary study of ten
infants using submental ultrasound assessment detected a
change in nipple position and tongue movement during a
feed following frenotomy [14].
An RCT in Southampton, UK, in 2002 identified infants
with a tongue-tie who were experiencing breastfeeding
problems [8]. Fifty-seven infants were randomly assigned
to have immediate frenotomy by the lactation consultant/
infant feeding specialist or to receive help with position-
ing and attachment by the lactation consultant and review
in 48 hours. They found that releasing the tongue-tie
improved feeding in 27 out of 28 infants, compared to 1
out of 29 who improved without release [8].
As there is no generally agreed definition of tongue-tie, a
quantitative instrument has been developed: the Hazel-
baker Assessment Tool for Lingual Frenulum Function
(HATLFF) [15]. Alison Hazelbaker stated "Because of my
Dot-plot of new Function ScoreFigure 1
Dot-plot of new Function Score.
1
2
3
4
5
6
New Function Score
tongue-tie
control
group
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Table 1: Hazelbaker Assessment Tool for Lingual Frenulum Function (1998 version)
Appearance Items
Appearance of tongue when lifted
2: Round OR square
1: Slight cleft in tip apparent
0: Heart-shaped
Elasticity of frenulum
2: Very elastic (excellent)
1: Moderately elastic
0: Little OR no elasticity
Length of lingual frenulum when tongue lifted
2: More than 1 cm OR embedded in tongue
1: 1 cm
0: Less than 1 cm
Attachment of lingual frenulum to tongue:
2: Posterior to tip
1: At tip
0: Notched tip
Attachment of lingual frenulum to inferior alveolar ridge
2: Attached to floor of mouth OR well below ridge
1: Attached just below ridge
0: Attached at ridge
Function Items
Lateralization
2: Complete
1: Body of tongue but not tongue tip
0: None
Lift of tongue
2: Tip to mid-mouth
1: Only edges to mid-mouth
0: Tip stays at alveolar ridge or rises to mid-mouth only with jaw closure
Extension of tongue:
2: Tip over lower lip
1: Tip over lower gum only
0: Neither of above, OR anterior or mid-tongue humps
Spread of anterior tongue
2: Complete
1: Moderate OR partial
0: Little OR none
Cupping
2: Entire edge, firm cup
1: Side edges only, moderate cup
0: Poor OR no cup
Peristalsis:
2: Complete, anterior to posterior (originates at the tip)
1: Partial: originating posterior to tip
0: None OR reverse peristalsis
Snapback
2: None
1: Periodic
0: Frequent OR with each suck
©
Alison K. Hazelbaker, MA, IBCLC July 1 1998
14 = Perfect score (regardless of Appearance Item score)
11 = Acceptable if Appearance Item score is 10
<11 = Function impaired. Frenotomy should be considered if management fails. Frenotomy necessary if Appearance Item score is <8.
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personal experiences with ankyloglossia and my frustra-
tion with the lack of a formal way to assess its presence in
breastfed infants, I wanted to develop an assessment
approach that would make it easier to determine the
extent of the impact that tongue-tie had on tongue mobil-
ity in the breastfed baby" [15] p47]. Five appearance
items, such as length of lingual frenulum (>1 cm, 1 cm, <1
cm) and seven function items, such as extension of the
tongue (tip over the lower lip, tip over lower gum only,
neither) are assessed (See Table 1). Ballard and colleagues
have explained how to score each item [1]. Hazelbaker
has demonstrated that the tool has content validity, how-
ever, it needs to be formally assessed for reliability [1],
and this was the aim of this study.
Method
The primary hypotheses were that:
1. Two assessors will give infants referred for tongue-tie
similar recommendations for release based on the Hazel-
baker Assessment Tool for Lingual Frenulum with an
inter-rater reliability of at least 0.75 (kappa).
2. Two assessors will give normal infants similar recom-
mendations based on the Hazelbaker Assessment Tool for
Lingual Frenulum with an inter-rater reliability of at least
0.6 (kappa).
Infants referred to the Breastfeeding Education and Sup-
port Service (BESS) at The Royal Women's Hospital for
assessment of tongue-tie were assessed by the BESS medi-
cal practitioner (LHA) and a second assessor, one of the
BESS lactation consultants (usually JPJ). A convenience
sample of healthy infants attending BESS was also
assessed by two assessors. Parents were informed about
the study, given a Plain Language Statement and signed
the Informed Consent form before participating.
Basic demographic information was collected, including
age of mother and baby, parity, mother's level of educa-
tion and private health insurance. Information about
breastfeeding and family history of tongue-tie was also
collected.
The infants were assessed by two assessors, who each com-
pleted the HATLFF independently prior to a feed.
Inter-rater reliability was measured using kappa for agree-
ment between the assessors on recommendation for
tongue-tie release. Kappa is a measurement of the propor-
tion of potential agreement beyond chance (actual agree-
ment beyond chance/potential agreement beyond
chance) [16]. Some experts have described the value of
kappa as 0 to 0.2 as "slight", 0.2 to 0.4 as "fair", 0.4 to 0.6
as "moderate", 0.6 to 0.8 as "substantial" and 0.8 to 1.0 as
"almost perfect" [16]. In most clinical examinations,
agreement between examiners is not perfect, and a kappa
of 0.4 is common [16]. Cronbach's alpha was used to
examine the correlation between the items. Cronbach's
alpha measures the inter-item correlations, ie how closely
the items fit together to describe something. It is recom-
mended that the value of alpha should be between 0.70
and 0.90 [17]. In the group of infants assessed for tongue-
tie, we expected approximately 75% of infants to be
scored as recommending frenulum release (from previous
study) [11]. Assuming a kappa of 0.75 with a precision of
0.2, the sample size would be 48 infants. Sample size cal-
culated using Stata 8.0 (sskdlg procedure). Therefore we
planned to recruit 50 infants with tongue-tie and 50 con-
trol infants.
The study was approved by The Royal Women's Hospital
Research and Ethics Committee (04/24, 7 Sept 2004) and
the University of Melbourne (HREC 040676, 17 Sept
2004).
Table 2: Reliability of each item
Item Kappa P value
Appearance items
Appearance of tongue when lifted 0.54 <0.01
Elasticity of frenulum 0.53 <0.01
Length of lingual frenulum when tongue lifted 0.51 <0.01
Attachment of lingual frenulum to tongue 0.39 <0.01
Attachment of lingual frenulum to inferior alveolar ridge 0.62 <0.01
Function items
Lateralization 0.71 <0.01
Lift of tongue 0.67 <0.01
Extension of tongue 0.65 <0.01
Spread of anterior tongue -0.02 0.74
Cupping 0.01 0.44
Peristalsis 0.05 0.07
Snapback 0.03 0.38
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Results
Infants were recruited from September 2004 to April
2005. Fifty-eight infants with tongue-tie were recruited,
age range 1 day to 84 days, mean 17 days, median 10 days,
56% were male (32/57, 1 missing). There were 25 control
infants age with an age range from 7–55 days, mean 26,
median 22 days.
Table 2 shows the reliability of each item in the Assess-
ment Tool. The Appearance items received kappas
between about 0.4 to 0.6, which represents "moderate"
reliability. The first three Function items (lateralization,
lift and extension of tongue) had kappa values over 0.65
which indicates "substantial" agreement. The four Func-
tion items relating to infant sucking (spread, cupping, per-
istalsis and snapback) received low kappa values with
insignificant p values.
There was 96% agreement between the two assessors on
the recommendation for frenotomy (see Table 3). The
kappa statistic was 0.92, which represents excellent agree-
ment or "almost perfect" [16].
The items in each part of the assessment tool were exam-
ined to see how well the items fitted together. For the
seven Function items Cronbach's alpha was 0.5074 (ie
low). When the four items relating to the infant's sucking
were removed (spread, cupping, peristalsis and snap-
back), the three items remaining in the new Function
Score received a higher reliability with a Cronbach's alpha
of 0.8655. The five items contributing to the Appearance
Score had a Cronbach's alpha of 0.7487. This is an accept-
able reliability and did not alter if individual items were
dropped.
The dot-plot (Figure) shows the distribution of new Func-
tion scores: from 0 to 6. Most of the infants referred with
tongue-tie scored 4 or less, while most of the control
infants scored 5 or 6. Therefore a cut-off of "less than or
equal to 4" indicating a recommendation for frenotomy
was chosen for the new Function score. This new cut-off
has a high sensitivity and specificity with an area under
the ROC curve of 0.9948.
There was no difference in any recommendation (ie
whether to release or not) between the old Function score
and the new Function score. Therefore, there was no
change in the kappa statistic with the new shorter Func-
tion score: 0.92 (excellent agreement).
Discussion and conclusions
This is the first inter-rater reliability study of the Hazel-
baker Assessment Tool for Lingual Frenulum Function.
(The recent study by Ricke and colleagues compared inter-
rater reliability only on the first nine infants assessed
[18]).
We found that the HATLFF has a high reliability in recom-
mendation for frenotomy in a study of infants with
tongue-tie and control infants. The two assessors had a
high degree of agreement in each of the Appearance items
and the first three Function items, however there was a
lack of agreement between the assessors on each of the
four Function items related to infant sucking. We found
that it appears that the Function Score can be more simply
assessed using only the first three function items (ie not
scoring the sucking items).
Further research in this area is needed [19]. Currently,
there are a number of other studies underway, for example
in Canada, clinicians are developing a simpler tool to
assess tongue-tie in breastfed infants [20].
Competing interests
The authors declare that they have no competing interests.
Authors' contributions
LHA designed, conducted and analysed the study and
drafted the manuscript. JPJ participated in the design and
conduct of the study. SMD assisted in study design and
analysis. All authors read and approved the final manu-
script.
References
1. Ballard JL, Auer CE, Khory JC: Ankyloglossia: Assessment, inci-
dence, and effect of frenuloplasty on the breastfeeding dyad.
Pediatrics 2002, 110:e63.
2. Ballard J, Chantry C, Howard CR: ABM Clinical Protocol #11:
Guidelines for the evaluation and management of neonatal
ankyloglossia and its complications in the breastfeeding
Table 3: Assessors' recommendations.
Recommendation – Assessor 2
Recommendation – Assessor 1 Release No need to release Total
Release 56056
No need to release 3 24 27
Total 59 24 83
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International Breastfeeding Journal 2006, 1:3 http://www.internationalbreastfeedingjournal.com/content/1/1/3
Page 6 of 6
(page number not for citation purposes)
dyad. [http://www.rwh.org.au/rwhcpg/mater
nity.cfm?doc_id=7617].
3. Marmet C, Shell E, Marmet R: Neonatal frenotomy may be nec-
essary to correct breastfeeding problems. J Hum Lact 1990,
6:117-121.
4. Notestine GE: The importance of the identification of anky-
loglossia (short lingual frenulum) as a cause of breastfeeding
problems. J Hum Lact 1990, 6:113-115.
5. Nicholson WL: Tongue-tie (ankyloglossia) associated with
breastfeeding problems. J Hum Lact 1991, 7:82-84.
6. Jain E: Tongue-tie: its impact on breastfeeding. AARN News Lett
1995, 51:18.
7. Lalakea ML, Messner AH: Ankyloglossia: does it matter? Pediatr
Clin North Am 2003, 50:381-397.
8. Hogan M, Westcott C, Griffiths M: Randomized, controlled trial
of division of tongue-tie in infants with feeding problems. J
Paediatr Child Health 2005, 41:246-250.
9. The Royal Women's Hospital: Clinical Practice Guideline: Man-
agement of infants with tongue-tie. [http://www.rwh.org.au/
rwhcpg/maternity.cfm?doc_id=7617].
10. Griffiths DM: Do tongue ties affect breastfeeding? J Hum Lact
2004, 20:409-414.
11. Amir LH, James JP, Beatty J: Review of tongue-tie release at a
tertiary maternity hospital. J Paediatr Child Health 2005,
41:243-245.
12. Woolridge MW: The 'anatomy' of infant sucking. Midwifery
1986, 2:164-171.
13. Neifert MR: Breastmilk transfer: positioning, latch-on, and
screening for problems in milk transfer. Clin Obstet Gynecol
2004, 47:656-675.
14. Langton D, Ramsay D, Jacobs S, Gollow I, Simmer K: Efficacy of
frenulotomy for ankyloglossia in breast-fed infants. Perinatal
Society of Australia and New Zealand, 8th Annual Congress, Sydney, Aus-
tralia 2004:44.
15. Hazelbaker AK: The assessment tool for lingual frenulum func-
tion (ATLFF): Use in a lactation consultant private practice.
Pasadena, California, Pacific Oaks College; 1993.
16. Sackett DL, Haynes RB, Guyatt GH, Tugwell P: Clinical Epidemiol-
ogy: A Basic Science for Clinical Medicine. 2nd edition. Boston,
Little, Brown and Company; 1991.
17. Streiner DL, Norman GR: Health Measurement Scales: A Prac-
tical Guide to their Development and Use. Oxford, Oxford
University Press; 2001.
18. Ricke LA, Baker NJ, Madlon-Kay DJ, DeFore TA: Newborn tongue-
tie: prevalence and effect on breast-feeding. J Am Board Fam
Pract 2005, 18:1-7.
19. Bandolier: Tongue-tie: ankyloglossia. Bandolier "Evidence based
thinking about health care" 2004, 124:2.
20. Srinivasan A, Feldman P: Ankyloglossia in breastfeeding infants:
new and existing evidence about frenotomy and maternal
nipple pain: ; Chicago, USA. International Location Consultant Asso-
ciation Conference and Annual Meeting, Chicago, USA 2005:139-142.
