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Machine learning-based spirometry reference values for the Iranian population: a cross-sectional study from the
Mohammad Sadegh Loeloe1, Reyhane Sefidkar1, Seyyed Mohammad Tabatabaei2
1Center for Healthcare Data Modeling, Department of Biostatistics and Epidemiology, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
This study established new spirometry reference values for Iranian adults using KNN regression, outperforming existing equations. An Excel calculator is now available for accurate lung function assessment in Iranian adults.
Area of Science:
- Pulmonary Medicine
- Biostatistics
- Machine Learning
Background:
- Spirometry is crucial for assessing lung function.
- Existing spirometry norm values may not accurately represent diverse populations like Iranians.
- Accurate reference values are needed for reliable diagnosis and management of respiratory diseases.
Purpose of the Study:
- To determine spirometric norm values for healthy Iranian adults.
- To compare the accuracy of KNN regression with MLR and LMS models for predicting spirometric parameters.
- To evaluate the performance of the derived values against established GLI-Caucasian and Iranian equations.
Main Methods:
- Spirometric data from 998 healthy Iranian adults (PERSIAN study) were analyzed.
- K-Nearest Neighbors (KNN) regression was employed to derive reference values for FEV1, FVC, FEV1/FVC, and FEF25-75%.
- Model performance was validated using 5-fold cross-validation and Mean Squared Error (MSE), comparing KNN regression against Multiple Linear Regression (MLR) and Lambda-Mu-Sigma (LMS) models.
Main Results:
- KNN regression demonstrated superior accuracy in predicting spirometric parameters compared to MLR and LMS models.
- The derived spirometry values showed lower MSE than the GLI-Caucasian and existing Iranian equations, indicating better prediction for the Iranian population.
- Specifically, the MSE for predicted FVC in females was 0.159 using KNN regression, significantly lower than Iranian (0.344) and GLI-Caucasian (0.397) equations.
Conclusions:
- Machine learning, specifically KNN regression, provides a flexible and accurate method for establishing population-specific spirometry reference values.
- The developed spirometry reference values are tailored for the Iranian adult population.
- An Excel calculator based on these findings can aid healthcare professionals in precise lung function assessment for Iranian adults.
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