Cross-cultural adaptation, content validity, and item analysis of the Objective and Subjective Knowledge and HIV Testing Scale for the Brazilian population

Abstract Objectives To propose a Portuguese version of the Objective and Subjective Knowledge and HIV Testing Scale (OSK-HIV-TS), assess its content validity, and perform item analysis after administration to a sample of undergraduate students. Methods Three translators translated the OSK-HIV-TS into Portuguese. Judges evaluated each item of a consensus version of the translated instrument for semantic, idiomatic, cultural, and conceptual equivalence. A consensus committee reviewed a back-translation against the original version of the OSK-HIV-TS. Content validity was calculated with the content validity index (CVI) and item analysis was conducted using Classical Test Theory (CTT). Results The translated scale achieved semantic, idiomatic, conceptual, and cultural equivalence to the original version. A total of 491 undergraduate students participated and the distribution of students’ responses to the OSK-HIV-TS revealed a high proportion of correct answers. All items were classified as easy or very easy and only item 16 was classified having strong discrimination power according to the discrimination index. Conclusion The OSK-HIV-TS is a novel instrument in the Brazilian literature for assessing human immunodeficiency virus (HIV) knowledge and should inspire more research into HIV/acquired immunodeficiency syndrome (AIDS) behavior and associated factors, which, despite being essential and necessary, is still lacking in the Brazilian literature.


Introduction
According to several studies, 2-5 the disease's multiplication in young people can occur due to biological factors, such as an exposed histological system due to development of the reproductive system, psychological factors, due to impaired personal relations, formation and questions regarding sexuality, which can lead to varying partners, and social aspects, such as lack of knowledge regarding HIV, social inequality, prejudice, socioeconomic status, and functional and structural conditions of the health system.
In view of this, Cabral et al. 6

OSK-HIV-TS item analysis
Participants were classified based on their performance on the instrument using Kelley's 17 suggestion, which is to estimate cut-off points using the 27% of participants with the highest and lowest scores on the instrument. For the objective dimension of the OSK-HIV-TS, comprising 16 items, the cut-off points adopted to select the participants with the best and worst performances were 16 correct answers and ≤ 13 correct answers, respectively. Classical test theory (CTT) was used to assess the quality of OSK-HIV-TS items, using the facility and discrimination indices as parameters. 18 For the facility index, the degree of facility of items is estimated through the proportion of correct answers, by which each item can be classified as "very easy" (proportion of correct answers from 80 to 100%), "easy" (60 to 80%), "medium difficulty" (40-60%), "difficult" (20-40%), or "very difficult" (0-20%). The discrimination index allows researchers to assess how well an item can distinguish between respondents who gave the best and worst responses on the instrument. In other words, the bigger the difference in the number of correct responses between participants with best and worse performance, the greater the item's discrimination power. Discrimination index results from 0 to 30% represent weak discrimination, rates from 30 to 60% indicate moderate discrimination, and indices from 60 to 100% demonstrate strong discrimination. 19 The goal of this analysis is therefore to find easy items with high discriminatory power (i.e., questions that are most likely to be answered correctly).

Discussion
Cross-cultural adaptation of an instrument is performed when there is a need to develop specific measures for countries other than where the scale was originally developed. This process needs rigorous methodology supported by a theoretical framework that can guide the translation, adaptation, and validation steps. 20  Although the original proposal focused on college students, we believe that the version proposed The quality of items of the OSK-HIV-TS for the Brazilian population, according to facility and discrimination indices obtained with CTT, is presented in Table 3.
All items were classified as easy or very easy when applied to the sample of undergraduate students. Only item 16 was classified as having strong discrimination.
here may be suitable for administration to Brazilian populations in different contexts, due to its simple and easy-to-understand language. However, we suggest that pre-tests of comprehensibility and applicability in the target population should always carried out before each application, so that the quality of the data obtained is guaranteed, especially in studies that involve data collection using the self-administered format. In addition, we hope that this scale can motivate further studies on behavior towards HIV/AIDS and associated factors, which are still scarce in the Brazilian literature, despite being urgent and necessary.

Conclusion
The