Development of a Measurement Tool to Assess Students' Knowledge and Perceptions About Cancer (SKPaC).

Cancer literacy is currently one of the most important dimensions of cancer continuum. Objective assessment of cancer knowledge in populations remains a challenging field to public health entities. Different evaluation tools are currently available; still, some groups remain disregarded due to the absence of validated instruments. Cancer literacy in adolescents and young adults has been clearly overlooked being a subject that requires new tools to be properly studied. To address this topic, we developed a new instrument and field tested it in a classroom environment for internal reliability, construct, and face validity. "Students Knowledge and Perceptions about Cancer questionnaire" was designed in Portuguese language and adapted to the Portuguese context by a multidisciplinary team. The final version of the questionnaire includes 35 items organized in three sections, encompassing knowledge and perceptions about cancer and socio-biographic data. Cancer experts ensured content validity, while tailoring of contents was refined with high school teachers. Test and retest of the instrument showed a good reliability of the scale and construct validity. Also, the clarity of the questionnaire and suitability to proper evaluate cancer knowledge was consistent between test and retest. The Students' Knowledge and Perceptions About Cancer Questionnaire (SKPaC) showed to be a valid tool to assess adolescents' knowledge and perceptions about cancer that can be used in the educational context.