Psychometric properties of the «International Fitness Scale» in Chilean youth

Abstract

In recent years, an instrument, known as the International Fitness Scale, was developed in order to indirectly assess physical fitness. The aim of the present study was to analyze the psychometric properties of validity and reliability of the International Fitness Scale in a sample of Chilean adolescents. The sample selected for assessing the instrument's validity was composed by 1,000 adolescents aged 12 to 18 (48.8% girls). With regard to reliability analysis, a sub-sample of 89 participants (37.8% girls) was employed. Internal consistency was assessed using Cronbach's alpha. Exploratory factor analysis was carried out in order to measure the construct validity, while convergent validity was assessed applying the known groups method. Results showed that the scale is consistent and valid, presenting moderate reliability. The International Fitness Scale has been proved to be a valid and reliable tool for fitness assessment in Chilean adolescents. This instrument could help economizing equipment, time and personnel in the assessment of Physical Fitness in Chilean youth.