title: Design and validation of a self-administered test to assess bullying (bull-M) in high school Mexicans: a pilot study.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Av, Plutarco Elías Calles y Hermanos Escobar s/n, Ciudad Juárez, Chihuahua, Mexico. aramos@uacj.mx
authors.forename: Arnulfo
authors.initials: A
authors.lastname: Ramos-Jimenez
authors.forename: Abraham
authors.initials: A
authors.lastname: Wall-Medrano
authors.forename: Oscar Esparza-Del
authors.initials: OE
authors.lastname: Villar
authors.forename: Rosa P
authors.initials: RP
authors.lastname: Hernández-Torres
mesh_terms: D000293:Adolescent; D058445:Bullying / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D010865:Pilot Projects; D011594:Psychometrics / Q000592:standards; D015203:Reproducibility of Results; D012574:Schools / Q000706:statistics & numerical data*; D057566:Self Report / Q000592:standards*; D013334:Students / Q000523:psychology / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D055815:Young Adult