(Post last updated June 24, 2022)
Review panel summary
The Derived Chemistry Anxiety Rating Scale (DCARS) is a 36-item instrument that was developed to measure anxiety associated with learning chemistry, being evaluated in chemistry, and handling chemicals. The instrument uses a Likert-type scale that ranges from 1 (“not at all” anxious) to 5 (“extremely” anxious). The DCARS was derived from the Revised Mathematics Anxiety Rating Scale (RMARS) that measures math anxiety. Evidence for test content validity was explored through interviews with eight chemistry students who were selected based on their self-reported high anxiety associated with learning chemistry and handling chemicals [1]. The authors stated that the interview results indicated that the instrument was not capturing all aspects of student anxiety toward chemistry. Therefore, they aligned two items on the DCARS with topics that students discussed in the interviews about their anxiety toward chemistry. In addition, they eliminated items from the instrument based on a “not at all” anxious response from >70% of students [1]. The panel saw this as weak evidence for test content validity. Relation to other variables was explored by comparing total scores between the DCARS and instruments used to measure math and trait anxiety [1]. The authors provided evidence that these three types of anxiety were related but distinct through correlations and analysis of variance overlap. Internal structure was explored through factor analysis to ensure the three-factor structure, however the authors do not report any of the results from the factor analysis [1]. Single-administration reliability was reported through acceptable coefficient alpha estimates for both the total DCARS score and each subscale [1].
Recommendations for use
The DCARS was developed to measure anxiety associated with learning chemistry, being evaluated in chemistry, and handling chemicals. The panel felt that additional evidence for validity and reliability of interpretations were warranted for this instrument. Evidence was provided for the hypothesized internal structure of the three subscales, however, as details of the internal structure evidence was missing from the factor analysis result [1], we encourage future work to support this proposed structure. In addition, there was insufficient internal structure validity evidence to support the use of the DCARS as a total score. Overall, more evidence for validity of the data obtained from the DCARS would provide support for confidently interpreting the data to represent chemistry student’s various anxieties.
Details from panel review
The authors provided some evidence for validity and reliability for data collected by the DCARS [1]. The interviews with students to explore test content only supported the use of two items on the 36-item DCARS. The validity evidence provided through relations with other variables did not have cited literature support for the conclusions presented. The results from the factor analysis were not reported to support the internal structure of the DCARS. Because of the limited evidence presented, the panel recommends caution of the interpretations of data from the DCARS.
References
[1] Eddy, R.M. (2000). Chemophobia in the college classroom: Extent, sources, and student characteristics. Journal of Chemical Education, 77(4), 514-517. https://doi.org/10.1021/ed077p514
[2] Widanski, B.B., & McCarthy, W.C. (2009). Assessment of chemistry anxiety in a two-year college. Journal of Chemical Education, 86(12), 1447-1449. https://doi.org/10.1021/ed086p1447