The objective of this study is to adapt the Modified Health Locus of Contro
l Scale (HLOC) (Kelly, et al., 1990) to Spanish and to evaluate teenager's
perceived control about the infection of HIV in order to be able to prevent
it. It is a study aimed at attaining a final edited test that is understoo
d by the intended sample of adolescents with and without psychological diso
rders. The adaptation process is divided into ten phases: 1) the translatio
n of the instrument from English to Spanish; 2) a revision of the translati
on by two expert translators; 3) inclusion of the pertinent changes as sugg
ested by the expert translators who evaluated the translation; 4) a revisio
n of the edited items by 9 Spanish expert judges in areas related to HIV/AI
DS, health psychology, preventive psychology, etc.; 5) an analysis of the r
esults; 6) inclusion of the changes indicated by the expert judges for the
edited items that hold an agreement percentage inferior to 85%; 7) the eval
uation of item comprehension in two groups of adolescents one with and one
without psychological disorders; 8) an analysis of the results for each one
of the sample groups and for the total sample of adolescents: 9) inclusion
of some of the changes in language terms for those items that did not reac
h an agreement percentage of 85% in stated comprehension and; 10) the elabo
ration of the final instrument. Key words: HIV/AIDS, adolescents, locus of
control, prevention, adaptation, Spanish.