Background: Among the various investigation modalities available, pulmonary function test (PFT) is an invaluable tool for the assessment of lung function. PFT values are influenced by race .age, sex, height, weight as well as environmental, genetic, socio-ecnomocal and technical parameters.

Objective: To determine pulmonary functions in the age group 7-15 years and to find its correlation with regards to age, sex, height, weight and body mass index.

Materials and Methods: This study was conducted among normal healthy school children of kannur aged 7 to 15 years . With preformed questionnaire children were interviewed, children with previous history of asthma and other chronic lung diseases were excluded, detailed general physical and systemic examination was done. Height, weight, body mass index were measured. All included children were tested in a sitting position with the head straight after taking written consent from parents. Spirometry was done using Micromedical Gold standard fully computerized portable auto spirometer (Superspiro Cat No. SU 6000). Statistical analysis of the data was done with SPSSv24.

Results: There were 166 children 111 boys and55 girls. Minimum FVC WAS 1.20L and maximum FVC was 3.80lMinimum FEV1was1.07 and maximum FEV1 was3.02l. FVC, FEV 1 and PEFR were found to be statistically significant in the study groups. For FVC and FEV 1, highest correlation was found with height and weight in both boys and girls.  PEFR showed weak correlation with weight in boys

Conclusion: Variables such as FVC, FEV 1 show good positive correlation with height, age and body mass index in both sexes. There is a need to have regional values for the prediction of normal spirometric parameters in a country like India with considerable diversity.

Keywords: Pulmonary Function Test, Forced Vital Capacity, Peak Expiratory Flow Rate (PEFR).

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Dr Muhammad Shafeek. K.

Assistant Professor, Department of Respiratory Medicine, Pariyaram Medical College, Kannur, Kerala