The chest expansion is measured with the help of measuring tape which is a reliable method of assessment of rib cage mobility, expansion of lung and thorax. Various spinal deformities, neurological diseases and respiratory diseases affect the chest excursion. It is essential to have a local database of reference values of chest expansion for accurate diagnosis of the respiratory diseases affecting lung and thorax. This study was carried out to determine chest excursion reference value for Indian children. A cross sectional observational study was conducted in 455 school going children aged 6-15 years Navi-Mumbai and Mumbai metropolitan region. The weight, height, age was recorded. The expansion of chest was measured in sitting at 3 levels i.e. axillary level, mammary level and xiphoid level. The descriptive statistics was used to find out mean, standard deviation values.   Mean chest expansion in 6 to 8.11 years age group was 4.45 cm at axillary level, 4.02 cm at mammary level, 3.73 cm at xiphoid level. Mean chest expansion in the 9 to 11.11 years age group was 5.22 cm at axillary level, 4.73 cm at mammary level, 4.41 cm at xiphoid level. Mean chest expansion in the 12 to 15 years age group was 5.82 cm at axillary level, 5.28 cm at mammary level, 4.89 cm at xiphoid level. The chest expansion was more in age group 12 to 15. The chest expansion was higher at the mammary level. Chest expansion increases in the growing age group. The reference values depend on genetic, environmental, dietary factors. Hence there is a need to establish the local reference data for chest expansion.

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