Development and validation of a body dissatisfaction scale for adolescents

In Spain there is a lack of specific instruments for the evaluation of deviance of the body image in adolescents. The aim of this research was to design and to validate a specific instrument for the evaluation of adolescent body dissatisfaction. We carried out 6 studies utilizing 2 samples of 91 and 569 school adolescents aged 12 to 19 years. In studies 1, 2 and 3 we designed a questionnaire with items selected from the bibliography to analyze the discriminate power. In studies 4, 5 and 6, various indexes of reliability and validity were calculated and scores were typified. The eventual questionnaire was made up of 32 items with 6 categories of responses. The reliability for the scale was: Cronbach's alpha for the whole sample, 0.91 (from 0.66 in the group of boys aged 17-19 years to 0.93 in the group of girls aged 14-16 years). The concurrent validity led to indexes between 0.67 and 0.89 using other instruments, and the factorial analysis showed 4 factors explaining 50.3% of the variance. Our research provides a new instrument for the evaluation of body dissatisfaction. This instrument is designed specifically for adolescents and has a good reliability and validity when compared to other available instruments.