Respiratory Oscillometry - Establishing Reference Values in Polish Children and Adolescents Aged 3-18 Years (OSCILLONiCA-PL-Kids)
Conditions: Healthy, Pulmonary Function Test
Sponsor: Medical University of Gdansk

Protocol ID: OSCILLONiCA-PL-Kids 01-2023
Version: 1.1
Date: September 19, 2025
Study Protocol
Official Title:Respiratory Oscillometry – Establishing Reference Values in
Polish Children and Adolescents Aged 3–18 Years (OSCILLONiCA-PL-
Kids)
Acronym: OSCILLONiCA-PL
NCT Number: NCTXXXXXXXX
Coordinating Center: Medical University of Gdańsk
Principal Investigator: Eliza Wasilewska, MD, PhD
Sponsor: Non-commercial investigator-initiated study
Synopsis
Primary Objective: Establish normative reference values for respiratory oscillometry (IOS) 
parameters (Rrs, Xrs, Fres, AX) in healthy Polish children and adolescents aged 3–18 years.
Secondary Objectives:
- Develop prediction equations.
- Create nomograms and percentile charts.
- Compare with international datasets.
- Evaluate feasibility of school-based oscillometry testing.
Study Design: Multicenter, observational, cross-sectional.
Population: Healthy Polish children and adolescents aged 3–18 years. 
Sample Size: ~2,500.
Timeline: Start January 2023, data collection until June 2025, analysis and publications 
2026.
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1. Background and Rationale
Respiratory diseases are common causes of morbidity in children. Spirometry is the gold 
standard of lung function testing but requires patient cooperation, limiting its use in 
preschoolers. Impulse oscillometry (IOS) is non-invasive and feasible from age 3, requiring 
only tidal breathing. Despite its growing use, no Polish population-specific reference values
exist. The European Respiratory Society (ERS) emphasizes the need for local reference 
equations. This study addresses this gap.
2. Objectives
Primary Objective: To establish reference values for IOS in healthy Polish children and 
adolescents aged 3–18 years.  
Secondary Objectives include developing prediction equations, analyzing variability, comparing 
with other countries, creating nomograms, and establishing an open database.
3. Study Design
This is a multicenter, cross-sectional, observational study coordinated by the Polish Society
of Pediatric Pulmonology across 12 centers in Poland. The study follows ERS technical 
standards and SPIRIT guidelines for observational protocols.
4. Study Population
Inclusion Criteria
Age 3–18 years.
Caucasian (born and residing in Poland).
Healthy children as defined by: no chronic lung disease; normal growth per WHO charts; 
no wheezing, cough, or dyspnea in the last 12 months; no acute respiratory infection 
within 4 weeks.
Written informed consent from parents/guardians; assent from adolescents ≥16 years.
Exclusion Criteria
History of asthma, cystic fibrosis, bronchopulmonary dysplasia, interstitial lung disease.
Acute respiratory infection within 4 weeks prior to testing.
Severe comorbidities (congenital heart disease, neuromuscular disorders).
Chest wall deformities.
Inability to perform IOS according to ERS standards.
5. Recruitment and Sampling
Participants are recruited through schools, kindergartens, and pediatric outpatient clinics in 
12 centers across Poland. Recruitment includes distribution of information sheets, informed 
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consent forms, and health questionnaires to parents. Non-probability (convenience) 
sampling is applied, ensuring representation across age, sex, and geographic regions.
6. Study Procedures
Training of Operators
All staff complete centralized training including physiology of oscillometry, interpretation of 
artifacts, and hands-on demonstrations. Certification is required before participation; 
refresher training and audits are conducted periodically. 
      Environment and Setup
Measurements are conducted in quiet school rooms, typically the nurse’s office. Equipment
includes oscillometer (Jaeger), stadiometer, and weighing scale. Calibration is performed
daily per manufacturer’s recommendations.
Anthropometry
Height measured barefoot using stadiometer, weight measured in light clothing. Data 
recorded into study database. BMI calculated for descriptive analyses.
Oscillometry Testing
Participants seated, back supported, head neutral, nose clip applied. Cheeks supported by 
examiner. Children breathe quietly through a mouthpiece for 30–45 seconds. At least 3 
technically acceptable recordings obtained. Median values analyzed. Criteria: no coughing, 
talking, leaks; repeatability ≤15% CoV. Parameters recorded: Rrs5, Rrs10, Rrs20, Xrs5, 
Xrs10, Xrs20, Fres, AX.
7. Equipment and Standardization
All centers use identical Jaeger oscillometers with standardized SOPs. Disposable 
mouthpieces provided. Centralized training, SOP manuals, and regular audits ensure 
consistency.
8. Statistical Analysis Plan
Sample size: ~2,500 participants. Data integrity checked automatically. Reference 
equations developed using Generalized Additive Models for Location, Scale and Shape 
(GAMLSS), LMS method. Model selection guided by Schwarz Bayesian Criterion. 
Comparisons with international cohorts performed. Sensitivity analyses exclude borderline 
cases (e.g., parental smoking exposure).
9. Ethics and Regulatory Aspects
Approved by the Bioethics Committee of the Medical University of Gdansk (No. 
106/2023). Complies with Declaration of Helsinki. Informed consent from 
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parents/guardians; assent from children ≥16 years. Confidentiality and GDPR compliance 
ensured.
10.Data Management and Quality Assurance
Data entered into encrypted system; identifiers separated from clinical data. Local 
coordinators oversee SOP adherence. Central monitoring and audits applied. Paper consent
forms stored securely for 10 years.
11. Dissemination and Impact
Findings disseminated via peer-reviewed journals, conferences, and guidelines of the Polish 
Society of Pediatric Pulmonology. De-identified datasets available upon request. Results 
expected to support clinical practice and GLI initiatives.
12.Patient and Public Involvement
Parents and schools engaged through meetings and written materials. Health 
questionnaire pilot-tested for clarity. Lay summaries of results will be distributed to 
schools and families.
13.Study Status and Timeline
Start: January 2023. Data collection until June 2025. Analysis: 2025–2026. Results 
publication planned for 2026.
14.Strengths and Limitations
Strengths: large multicenter sample, standardized devices and SOPs, wide age coverage, 
alignment with ERS standards.
Limitations: underrepresentation of rural schools, smaller subsamples at youngest and 
oldest ages, residual variability.
15.Funding, Conflicts of Interest, Acknowledgements
Funding: Medical University of Gdańsk. No conflicts of interest declared. 
Acknowledgements: Polish Society of Pediatric Pulmonology, participating schools, parents,
and children.
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References
1. Oostveen E, MacLeod D, Lorino H, et al. The forced oscillation technique in 
clinical practice: methodology, recommendations and future developments. 
Eur Respir J. 2003;22(6):1026-1041. doi:10.1183/09031936.03.00010203.
2. King GG, Bates J, Berger KI, et al. Technical standards for respiratory 
oscillometry. Eur Respir J. 2020;55(2):1900753. doi:10.1183/13993003.00753-
2019.
3. Kaminsky DA, Simpson SJ, Berger KI, et al. Clinical significance and
applications of oscillometry. Eur Respir Rev. 2022;31(163):210208. 
doi:10.1183/16000617.0208-2021.
4. Shi Y, Wu J, Zhang H, et al. Reference values of impulse oscillometry (IOS) for
healthy Chinese children aged 4–17 years. Respir Res. 2022;23:182. 
doi:10.1186/s12931-022-02080-z.
5. Valach C, Wouters EFM, Ofenheimer A, et al. Oscillometry reference values 
for children and adolescents: LEAD cohort Austria. ERJ Open Res. 2024; 
PMID:39698065.
6. Park JH, Lee JH, et al. Reference values for respiratory system impedance 
using impulse oscillometry in Korean preschool children. Korean J Pediatr. 
2011;54(2):64-68. doi:10.3345/kjp.2011.54.2.64.
7. Chaya S, MacGinty R, Jacobs C, Githinji L, Hlengwa S, Simpson SJ, Zar HJ, 
Hantos Z, Gray DM Normal values of respiratory oscillometry in South 
African children and adolescents. ERJ Open Res. 2023 Apr 11;9(2):00371-
2022. doi: 10.1183/23120541.00371-2022. eCollection 2023 Mar.
8. Stoimenova P, Mandadzhieva S, Marinov B Reference Values for Respiratory 
Impedance in Bulgarian Children Aged 2-8 Years Using the Forced Oscillation
Technique (FOT). Children (Basel). 2025 Jul 21;12(7):957. doi: 
10.3390/children12070957.
9. Gochicoa-Rangel L, Torre-Bouscoulet L, Martínez-Briseño D, Rodríguez-Moreno
L, Cantú-González G, Vargas MH Values of impulse oscillometry in healthy 
mexican children and adolescents. Respir Care. 2015 Jan;60(1):119-27. doi: 
10.4187/respcare.03374. Epub 2014 Oct 21.PMID: 25336530
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10.4187/respcare.04226. Epub 2016 May 10.PMID: 27165421
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PMID: 18988256.
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Protocol ID: OSCILLONiCA-PL Kids-01-2023
Version: 1.1
Date: September 19, 2025
Inform Consent Form
Study: Oscillometry reference values for Polish children and 
adolescents
Official Title: Respiratory Oscillometry – Establishing Reference Values in Polish 
Children and Adolescents Aged 3–18 Years (OSCILLONiCA-PL Kids)
Acronym: OSCILLONiCA-PL Kids
Dear Parent/Guardian,
Your child is invited to participate in a multicenter scientific study aimed at establishing 
reference values for oscillometry (impulse oscillometry, IOS) in healthy Polish children and 
adolescents. The study is coordinated by the Polish Society of Paediatric Pulmonology.
Purpose of the study
The purpose of this study is to determine normal ranges of oscillometric parameters of lung 
function in children and adolescents aged 3–18 years. These results will help physicians in 
Poland and worldwide to better diagnose and monitor respiratory diseases in children.
Study procedures
- The examination will take place in your child’s school or kindergarten, in a designated
room.
- Your child’s height and weight will be measured.
- A short health questionnaire will be completed based on your information.
- Your child will undergo oscillometric lung function testing using a non-invasive, 
standardized device. The test involves quiet breathing into a mouthpiece for a short 
period (approx. 30–60 seconds).
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Risks and safety
The examination is safe, painless, and non-invasive. The only possible inconvenience may be 
mild fatigue or lack of cooperation during the test.
Data protection
All collected data will be anonymized and processed in accordance with the European Union 
General Data Protection Regulation (GDPR). Results will be used exclusively for scientific 
purposes.
Voluntary participation
Participation in this study is entirely voluntary. You may refuse or withdraw your consent 
at any time without giving a reason and without any consequences for your child.
Statement of consent
I hereby declare that I have read the above information and had the opportunity to ask 
questions. I understand the purpose and procedures of the study, and I voluntarily consent 
for my child to participate.
Child’s details
- Full name: .............................................................
- Date of birth: .........................................................
-Signature: ............................................................ Date: .................................................................
Parent/Guardian details
- Full name: .............................................................
- Signature: ............................................................ Date: .................................................................
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