Open Access Open Badges Research article

Design and validation of a self-administered test to assess bullying (bull-M) in high school Mexicans: a pilot study

Arnulfo Ramos-Jimenez1*, Abraham Wall-Medrano1, Oscar Esparza-Del Villar1 and Rosa P Hernández-Torres2

Author affiliations

1 Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Av. Plutarco Elías Calles y Hermanos Escobar s/n, Ciudad Juárez, Chihuahua, Mexico

2 Escuela de Educación Física y Ciencias del Deporte, Universidad Autónoma de Chihuahua, Chihuahua, Mexico

For all author emails, please log on.

Citation and License

BMC Public Health 2013, 13:334  doi:10.1186/1471-2458-13-334

Published: 11 April 2013



Bullying (Bull) is a public health problem worldwide, and Mexico is not exempt. However, its epidemiology and early detection in our country is limited, in part, by the lack of validated tests to ensure the respondents’ anonymity. The aim of this study was to validate a self-administered test (Bull-M) for assessing Bull among high-school Mexicans.


Experts and school teachers from highly violent areas of Ciudad Juarez (Chihuahua, México), reported common Bull behaviors. Then, a 10-item test was developed based on twelve of these behaviors; the students’ and peers’ participation in Bull acts and in some somatic consequences in Bull victims with a 5-point Likert frequency scale. Validation criteria were: content (CV, judges); reliability [Cronbach’s alpha (CA), test-retest (spearman correlation, rs)]; construct [principal component (PCA), confirmatory factor (CFA), goodness-of-fit (GF) analysis]; and convergent (Bull-M vs. Bull-S test) validity.


Bull-M showed good reliability (CA = 0.75, rs = 0.91; p < 0.001). Two factors were identified (PCA) and confirmed (CFA): “bullying me (victim)” and “bullying others (aggressor)”. GF indices were: Root mean square error of approximation (0.031), GF index (0.97), and normalized fit index (0.92). Bull-M was as good as Bull-S for measuring Bull prevalence.


Bull-M has a good reliability and convergent validity and a bi-modal factor structure for detecting Bull victims and aggressors; however, its external validity and sensitivity should be analyzed on a wider and different population.

School violence; Bullying; Mexico; Validation