The use of tests or scales in research on the reception of audiovisual content is widespread. Choosing a tool to measure the construct of interest is often a challenge as it must be based on empirical evidence that the scores can be used for the intended purposes. In recent years, there has been a growing body of research focusing on the representation of LGBTI+ characters in serialized fiction or film. Often, this research focuses either on the extent to which there are enough characters, or the extent to which these characters are stereotyped. With this kind of research, we have a basis for understanding how to work on reducing prejudice towards LGBTI+ people but it is not enough. Having measures that allow us to know the attitudes towards LGBTI+ people and characters in fiction, we can help us to make good diagnoses and educational interventions if necessary. However, there is currently a gap in the availability of tools to effectively measure these constructs. In this paper, we deal specifically with one case study: transphobia. Although several scales have been developed in the last decade (e.g., Genderism and Transphobia Scale, the Transphobia Scale, the Attitudes Toward Transgendered Individuals Scale), the evidence of psychometric quality is not as good as desirable. Not only from a quantitative point of view (e.g., factor analysis, reliability) but also from the point of view of their content: they generally only allow us to discriminate against people with extreme attitudes, not detecting, for example, more subtle forms of transphobia. In this paper we discuss the limitations and challenges based on the empirical results of two studies in order to seek possible solutions to the problems encountered. In the first study, a sample of 829 young Spanish people were administered the TABS scale (Trans Attitudes and Beliefs Scale) and the GTSS-R scale (Genderism and Transphobia Subscale-Revised). The second study was based on the responses of 310 young Spaniards who were also administered the ATTMW (Attitudes toward Trans Men and Women). To this end, firstly, the lack of variability in the responses obtained is discussed. In other words, we found polarized opinions, generally with favorable attitudes towards transgender people. This is not surprising when looking at the content of the items, since unless the person has a very transphobic attitude, it is difficult to disagree (e.g., “Transgender individuals should be treated with the same respect and dignity as any other person”). This finding can be thought as positive, as we might think that people in general are not transphobic. However, it could also mean that there is a problem in the definition of the construct of transphobia, not of people scoring low on the instruments. Another problem we face is that the different tools intended to measure attitudes towards LGBT people do not discriminate between them either. In the case of the TABS and the GTSS-R, which have substantively differently nuanced definitions, we found a very high correlation (0.72), while other instruments like the Modern Homophobia scales (MHS-L/MHS-G) we found more modest correlations (-.50). Although a relationship between the concepts is expected, the scales present potential issues of discriminating between the different concepts they intend to measure. Finally, the ATTMW presents transphobia as conceptually different towards trans men and trans women, thus it provides a unique scale for each. However, the empirical evidence shows a very high correlation between these two scales (0.98), suggesting a common root in these constructs. When relating this scale also to other scales, we also find high correlations with heterosexism (0.75), again suggesting that these constructs have common roots. In this landscape, we propose practical recommendations on how to overcome some of these limitations and challenges. From the proposal of new scales that aim to measure more subtle forms of transphobia, to the improvement of the response process of some of these scales. This way the field could simplify the measurement of the constructs and benefit from more psychometrically robust measures.