Assessing the validity and reliability of questionnaires on the implementation of Indonesian curriculum K-13 in STEM

The study aimed to investigate how well educators of STEM-related subjects understood and implemented the K-13 curriculum in their classrooms. A forum group discussion (FGD) was held in March 2018, attended by 60 educators of STEM-related subjects in Banda Aceh and Aceh Besar Districts. The FGD aimed to investigate the challenges faced by secondary school teachers in implementing K-13 in STEM-related subjects, including Physics, Chemistry, Biology, and Mathematics. Since the K-13 curriculum was implemented in July 2013, there was no survey study to evaluate its implementation in Aceh. Therefore, surveys on the implementation of K-13 in STEM education and on the satisfaction of participants of the FGD were administered at the end of the FGD. The survey instruments were developed to measure participants' understanding and opinions regarding the implementation of K-13 in STEM education and their satisfaction of the FGD. The instruments were validated using classical test theory (CTT) analyses. The CTT analyses involved the estimation of the validity and reliability of the instruments. The validity of an instrument refers to the degree to which it measures what it purports to measure. Face validity, content validity, and construct validity are types of validity that were discussed in the study. Face validity represents the estimation of the clarity of the purpose of an instrument, while content validity represents the estimation of the propriety of content and its presentation. Construct validity represents the measure of the propriety of the constructs in the instrument. The study used the Dillman's Tailored Design Method to create the questionnaire blueprint. The content validity was estimated by asking experts in the content area to review the blueprint and the items in the instrument. The experts were given the list of content areas specified in the test blueprint along with the items. They were asked to indicate whether each item was matched to the contents indicated in the blueprint and whether the items represented the intended construct. The construct validity was calculated using the Pearson's correlation coefficient (PPMCC). The Pearson's correlation coefficient is a measure of the correlation between two variables. In this study, the Pearson's correlation coefficient was used to calculate the convergent validity and discriminant validity of the instruments. The convergent validity represents the correlation between a measure of a construct and other measures that are theoretically related to the construct. The discriminant validity represents the correlation between a measure of a construct and other measures that are theoretically unrelated to the construct. The results of the CTT analyses showed that the questionnaires had good internal consistency reliability and validity. The Cronbach's alpha of the FGD satisfaction responses was 0.838, while the Cronbach's alpha of the implementation of K-13 responses was 0.882. The validity values of the items in the participants' understanding and opinions regarding the implementation of K-13 in STEM education ranged from 0.632 to 0.821. The validity values of the items in the implementation of K-13 responses ranged from 0.584 to 0.821. The study concluded that the questionnaires had good internal consistency reliability and validity. The results of the CTT analyses provided evidence that the questionnaires were valid and reliable instruments for measuring participants' understanding and opinions regarding the implementation of K-13 in STEM education and their satisfaction of the FGD.