Out-of-field (OOF) teaching is a widespread international practice, whereby teachers instruct subjects in which they hold no formal education (Price et al., 2019). While it can be regarded as an effective means of overcoming the shortage of (specialist) teachers, there are also critical views regarding the quality of OOF teaching (Hobbs & Porsch, 2021; Porsch & Whannell, 2019). The assumption is that OOF teachers have a lower level of content and pedagogical content knowledge due to a lack of learning opportunities in their formal education. This can adversely impact the quality of instruction, which can negatively impact student outcomes (Baumert et al., 2010; Goldhaber & Brewer, 2000).  

As summarized by Price et al. (2019)​, the proportion of OOF teaching varies significantly between countries, subjects, and school grades. The initial analysis of TIMSS 2023 data revealed substantial variation in the proportion of OOF teaching in mathematics. In Austria, for instance, only 8% of eighth-grade students are taught by teachers without a major in mathematics education, whereas in Finland, this figure is 81%. Similar disparities are observed in science, with 13% OOF teaching in Hungary and 95% in South Africa. These differences reflect the diverse structural, cultural, and economic contexts in which OOF teaching occurs. Considering these complexities, this proposal investigates how variations in student outcomes, both cognitive and non-cognitive, are linked to OOF teaching practices across nations.

Using the most recent TIMSS 2023 data, the analyses address the following research questions:

1. Can country differences in student (cognitive and non-cognitive) mathematics outcomes be explained by variations in the prevalence of OOF teaching between countries?
2. Can country differences in student (cognitive and non-cognitive) science outcomes be explained by variations in the prevalence of OOF teaching between countries?

Theoretical and Educational Significance

OOF teachers lack subject-specific learning opportunities in their formal education, leading to deficiencies in content and pedagogical knowledge (Baumert et al., 2010). This lack of knowledge may impact the quality of teaching and instructional effectiveness, subsequently affecting student performance. However, OOF teaching is not only associated with a lack of specific knowledge but also with deficiencies in factors such as motivational orientation and self-efficacy (Porsch, 2016), which, in turn, may also affect student outcomes via teaching practice (Burić & Kim, 2020).

OOF teachers often rate their teaching quality lower (Porsch & Wilden, 2022)  and there are notable deficiencies in perceptions of personal competence and self-efficacy beliefs in OOF teaching (Porsch, 2016). Moreover, teachers in OOF teaching often lack the ability to bridge complex concepts, connect content to students' prior knowledge, and address diverse learning needs (Du Plessis, 2015).

The challenges associated with OOF teaching can adversely impact instructional quality. Research has demonstrated the significance of teachers' influence on student performance and non-cognitive factors such as motivation and self-efficacy (López-Martín et al., 2023).

However, the relationship between OOF teaching and student outcomes varies significantly across studies (Porsch & Whannell, 2019), calling for nuanced, context-sensitive international research. International comparisons of the effects of OOF teaching are still scarce. Nevertheless, a recent study by Hanfstingl et al. (2023) attempted to address this gap by concluding that country differences in the proportion of OOF teachers is indeed significantly associated with country differences in students' enjoyment of science and scientific literacy.

The present paper aims to provide further international insights and extend the analysis of mathematics and science outcomes, which is crucial for the development of effective strategies to mitigate the negative effects of OOF teaching and enhance educational quality on a global scale.

The present study uses data from 8th graders from the most recent TIMSS 2023 study. The international nature of the dataset is beneficial because it combines achievement results in mathematics and science with questionnaires addressing non-cognitive outcomes and information regarding the class, particularly teacher characteristics. With a total of 44 participating countries and representative samples within countries, the data provides an ideal base for international comparison, enabling a more comprehensive analysis of teaching OOF. The study will utilize the proportion of OOF teaching to explain variations in mathematics and science achievement, encompassing assessments in knowing, applying, and reasoning within specific content areas. Non-cognitive outcomes are represented by students’ intrinsic motivation, measured using nine items on a 4-point Likert scale (e.g., "I enjoy learning mathematics/science"). The inclusion of non-cognitive variables will provide a holistic perspective on the effects of OOF teaching. To address the complexities inherent in international comparisons, this study employs a multilevel modeling approach. This methodology accounts for structural, cultural, and economic differences across countries, ensuring robust and context-sensitive findings. Multilevel modeling is particularly useful in educational research because it accounts for the hierarchical structure of the data, such as students nested within classes and schools (Raudenbush & Bryk, 2002). This methodological framework enables the examination of both the within and between-country effects of OOF teaching on student outcomes.

This research makes a significant contribution to the expanding body of literature on teacher competence and student outcomes by offering a thorough analysis of OOF teaching on an international scale. Using TIMSS 2023 data and advanced methods, this study will provide nuanced insights into the influence of OOF teaching on both cognitive and non-cognitive aspects of student learning. The findings have substantial implications for educational policy and practice, particularly in addressing teacher shortages and enhancing the quality of instruction worldwide.

Baumert, J., Kunter, M., Blum, W., Brunner, M., Voss, T., Jordan, A., Klusmann, U., Krauss, S., Neubrand, M. & Tsai, Y.‑M. (2010). Teachers’ Mathematical Knowledge, Cognitive Activation in the Classroom, and Student Progress. American Educational Research Journal, 47(1), 133–180. https://doi.org/10.3102/0002831209345157 Burić, I. & Kim, L. E. (2020). Teacher self-efficacy, instructional quality, and student motivational beliefs: An analysis using multilevel structural equation modeling. Learning and Instruction, 66, 101302. https://doi.org/10.1016/j.learninstruc.2019.101302 Goldhaber, D. D. & Brewer, D. J. (2000). Does Teacher Certification Matter? High School Teacher Certification Status and Student Achievement. Educational Evaluation and Policy Analysis, 22(2), 129–145. https://doi.org/10.2307/1164392 Hanfstingl, B., Gnambs, T., Porsch, R. & Jude, N. (2023). Exploring the association between non-specialised science teacher rates and student science literacy: an analysis of PISA data across 18 nations. International Journal of Science Education, 1–19. https://doi.org/10.1080/09500693.2023.2262729 Hobbs, L. & Porsch, R. (2021). Teaching out-of-field: challenges for teacher education. European Journal of Teacher Education, 44(5), 601–610. https://doi.org/10.1080/02619768.2021.1985280 López-Martín, E., Gutiérrez-de-Rozas, B., González-Benito, A. M. & Expósito-Casas, E. (2023). Why Do Teachers Matter? A Meta-Analytic Review of how Teacher Characteristics and Competencies Affect Students’ Academic Achievement. International Journal of Educational Research, 120, 102199. https://doi.org/10.1016/j.ijer.2023.102199 Porsch, R. (2016). Fachfremd unterrichten in Deutschland. Definition - Verbreitung - Auswirkungen [Out-of-field Teaching in Germany Definition – Frequency – Consequences]. Die deutsche Schule, 108, 9–32. https://doi.org/10.25656/01:25943 Porsch, R. & Whannell, R. (2019). Out-of-Field Teaching Affecting Students and Learning: What Is Known and Unknown. In L. Hobbs & G. Törner (Hrsg.), SpringerLink Bücher. Examining the Phenomenon of “Teaching Out-of-field”: International Perspectives on Teaching as a Non-specialist (S. 179–191). Springer Singapore. https://doi.org/10.1007/978-981-13-3366-8_7 Porsch, R. & Wilden, E. (2022). Teaching English Out-of-Field in Primary School: Differences in Professional Characteristics and Effects on Self-Assessed Instructional Quality. In L. Hobbs & R. Porsch (Hrsg.), Out-of-Field Teaching Across Teaching Disciplines and Contexts (1st ed. 2022, S. 117–134). University of Limerick. https://doi.org/10.1007/978-981-16-9328-1_6 Price, A., Vale, C., Porsch, R., Rahayu, E., Faulkner, F., Ríordáin, M. N., Crisan, C. & Luft, J. A. (2019). Teaching Out-of-Field Internationally. In L. Hobbs & G. Törner (Hrsg.), SpringerLink Bücher. Examining the Phenomenon of “Teaching Out-of-field”: International Perspectives on Teaching as a Non-specialist (S. 53–83). Springer Singapore. https://doi.org/10.1007/978-981-13-3366-8_3 Raudenbush, S. W. & Bryk, A. S. (2002). Hierarchical Linear Models: Applications and Data Analysis Methods. SAGE.