The role of the school principal as a central agent in the multi-level school system and the tension between autonomy and accountability are often associated with increased stress and work overload, which can lead to emotional exhaustion (Marsh et al., 2023). “Muddy” school governance and accountability structures can lead to a “field of opaque power relations” (Hangartner & Svaton, 2022, p. 247), further increasing the risk of stress. Furthermore, there are indications that the number of school leaders' working hours is increasing (Reid & Creed, 2023). In addition to the aforementioned complexity, this could (also) be related to the fact that principals have become (even) more available through digital tools, thus increasing their risk of being even more involved professionally (Creagh et al., 2023). This can have an impact on the work commitment and motivation to quit (Skaalvik, 2023). Compared to the research landscape from English-speaking countries and Scandinavia, school leadership research is still an emerging field in German-speaking countries. To date, there have been no studies from Switzerland that consider aspects of stress, self-efficacy and commitment among school leaders. This contribution addresses this desideratum. The Job Demands Resources model (JD-R model, Bakker & Demerouti, 2007) serves as a framework for investigating possible relationships between the extension of working hours, work overload and school commitment. According to this model, work demands, e.g. the extension of work, have a positive effect on perceived work overload, which in turn has a negative effect on school commitment. Furthermore, resources have a positive effect on school commitment and negatively moderate the relationship between work demands and work overload (Bakker & Demerouti, 2007). Some studies have already successfully transferred the model to the context of school leadership and workload (Marsh et al., 2022; Skaalvik, 2023). Self-efficacy appears to be an important personal resource (Gugliemi et al., 2012; Ophoff & Pfurtscheller, 2024).

The following hypotheses were formulated based on the research briefly described above:

1. extension of working hours has a significant positive effect on work overload.
2. self-efficacy has a significantly negative effect on work overload.
3. self-efficacy moderates the relationship between extension and work overload.
4. work overload has a significant negative effect on commitment.
5. extension has a significant negative effect on commitment.
6. self-efficacy has a significant positive effect on commitment.

The underlying data was collected using an online questionnaire. 4749 principals throughout Switzerland were contacted by email, after which 2035 took part. As answering all questions was optional, the final sample used for this analysis was N=1055. While the extension of working hours was measured with five items, work overload was operationalized with three items. Self-efficacy was measured with five items. School commitment was operationalized with three items. A structural equation model with mediation and the moderator self-efficacy was calculated.

The results from the structural equation model imply that extension has a significant positive effect on work overload and that work overload in turn is a significant negative predictor of commitment. However, extension has no significant direct effect on commitment. Self-efficacy is a significant negative predictor of work overload and has a significant positive effect on commitment. However, self-efficacy does not significantly moderate the relationship between work overload and commitment. 67.5% of the variance of the work overload factor is explained by the extension of working hours and self-efficacy, while 25.9% of the variance of the commitment factor is explained by all variables in the model. Contrary to the assumptions of the JD-R model and earlier studies from the pedagogical context, self-efficacy could not be identified as a protective factor regarding the experience of stress when working hours are extended.

Only validated items were used for the constructs. Regarding the extension of working hours, principals were asked to indicate on a Likert-scale from one (never) to six (very often) how often they had given up leisure time in favor of work in the past three months. The five items for this construct were adopted from the survey by Krause et al. (2015). The scale has a Cronbach’s alpha of .77. For work overload a three-item scale based on Schulz et al. (2004) was used. Principals were asked to state how often on a scale from one (never) to five (very often) they had experienced stressful situations in the past three months. Reliability analysis showed a Cronbach’s alpha of .83. Self-efficacy was operationalized with items referring to individual and collective self-efficacy of school-management following Schmitz and Schwarzer (2002) with a Cronbach’s alpha of .70. Whereas individual self-efficacy is related to the confidence of the principal to effectively lead the teachers and foster innovation, collective self-efficacy mirrors the confidence to manage school projects and innovation effectively together with the teachers. Finally, for commitment the three-item scale by Greb et al. (2011) was chosen. On a scale ranging from one (totally disagree) to five (totally agree) principals were asked to indicate how much they identified themselves with the school and enjoyed working there. This resulted in a Cronbach’s alpha of .78. For the descriptive statistics, means and standard deviations of all constructs (self-efficacy, extension of working hours, work overload and commitment) were calculated. Regarding inferential statistics all constructs observed in this study were included in a correlation analysis. Since all these constructs were measured with three up to five items, which is ideal for structural equation modeling (SEM), this method was used for further analysis. To test all hypotheses except of hypothesis three, a SEM model was performed with self-efficacy as a predictor, work overload as the mediator and school-related commitment as the dependent variable. To investigate the moderating effect of self-efficacy regarding the relationship between extension of working time and work overload specified in hypothesis three another SEM model was conducted including the moderator. By doing this, self-efficacy and the extension of working hours were double mean centered as centering is required for SEM moderation analysis and Lin et al. (2010) indicated that double mean centering performs superior compared to other centering approaches especially when the assumption of normal distribution is violated.

The results of the study support most of the hypotheses: The extension of working hours has a significant and positive effect on work overload, whereas self-efficacy has a significant and negative impact on work overload. Furthermore, work overload has a significant negative impact on school-related commitment. By contrast, self-efficacy is a significant and positive predictor for commitment. These findings are aligning with previous studies using the JDR-model as a theoretical framework to investigate the work overload and its predictors in the context of school leadership (Marsh et al., 2022; Skaalvik, 2023). However, the extension of working hours has no significant direct effect on commitment. Surprisingly, the moderating effect of self-efficacy on the relationship between the extension of working hours and work overload cannot be supported by the present data. Previous findings highlight the importance of self-efficacy as a personal resource (see Gugliemi et al., 2022; Ophoff & Pfurtscheller, 2024). However, those studies did not investigate the moderating effect of self-efficacy on the relationship between job demands and the experience of work overload. By considering this moderation, the present study also reveals the limits of self-efficacy in the context of job demands and work overload of principals: If principals extensively extend their working hours, self-efficacy cannot serve as protective factor for experiencing work overload. This leads to important implications regarding the stress prevention of principals: It is not only important to strengthen their self-efficacy to avoid work overload, but also to offer classic stress training and possibly a reduction in working hours. Besides developing more confidence in individually and collectively managing school projects efficiently, principals need to observe themselves carefully, be sensitized to the side effects of the extension of working hours and plan enough leisure time to reduce work overload and stay committed to their schools in the long term.

Bakker, A. B., & Demerouti, E. (2007). The job demands‐resources model: State of the art. Journal of managerial psychology, 22(3), 309-328. https://doi.org/10.1108/02683940710733115 Creagh, S., Thompson, G., Mockler, N., Stacey, M., & Hogan, A. (2023). Workload, work intensification and time poverty for teachers and school leaders: A systematic research synthesis. Educational Review, 1-20. https://doi.org/10.1080/00131911.2023.2196607 Greb, K., Poloczek, S., Lipowsky, F., & Faust, G. (2011). Dokumentation der Erhebungsinstrumente des Projekts „Persönlichkeits- und Lernentwicklung von Grundschülern” (PERLE). 1. PERLE-Instrumente: Schüler, Lehrer & Eltern (Messzeitpunkt 1). GFPF, 177 S. - (Materialien zur Bildungsforschung; 23/1). https://doi.org/10.25656/01:3127 Groß Ophoff, J. & Pfurtscheller J. (2024). Schulleitung werden ist nicht schwer, Schulleitung bleiben umso mehr?: Belastungen und Ressourcen von Schulleitungen in Deutschland und Österreich. DDS – Die Deutsche Schule, 116(4), 366-378. https://doi.org/10.31244/dds.2024.04.04 Guglielmi, D., Simbula, S., Schaufeli, W. B., & Depolo, M. (2012). Self‐efficacy and workaholism as initiators of the job demands‐resources model. Career Development International, 17(4), 375-389. Hangartner, J., & Svaton, C. J. (2022). Distributed Leadership, Teacher Autonomy, and Power Relations Between Headteachers and Teachers Under Low-Stakes Accountability Conditions: An Ethnographic Account from Switzerland. Research in Educational Administration and Leadership, 7(2), 247–281. https://doi.org/10.30828/real.1063609 Krause, A., Baeriswyl, S., Berset, M., Deci, N., Dettmers, J., Dorsemagen, C., Meier, W., Schraner, S. Stetter, B. & Straub, L. (2015). Selbstgefährdung als Indikator für Mängel bei der Gestaltung mobil-flexibler Arbeit: Zur Entwicklung keines Erhebungsinstruments. Wirtschaftspsychologie, 4, 49-59. Lin, G. C., Wen, Z., Marsh, H. W., & Lin, H. S. (2010). Structural equation models of latent interactions: Clarification of orthogonalizing and double-mean-centering strategies. Structural Equation Modeling, 17(3), 374-391. https://doi.org/10.1080/10705511.2010.488999 Marsh, H. W., Dicke, T., Riley, P., Parker, P. D., Guo, J., Basarkod, G., & Martin, A. J. (2023). School principals' mental health and well‐being under threat: A longitudinal analysis of workplace demands, resources, burnout, and well‐being. Applied Psychology: Health and Well‐Being, 15(3), 999-1027. https://doi.org/10.1111/aphw.12423 Reid, D. B., & Creed, B. M. (2023). Visible at night: US school principal nontraditional work-hour activities and job satisfaction. Educational Management Administration & Leadership, 51(5), 1123–1140. https://doi.org/10.1177/17411432211027645 Skaalvik, C. (2023). Emotional exhaustion and job satisfaction among Norwegian school principals: Relations with perceived job demands and job resources. International Journal of Leadership in Education, 26(1), 75-99. https://doi.org/10.1080/13603124.2020.1791964 Schmitz, G. & Schwarzer, R. (2002). Individuelle und kollektive Selbstwirksamkeitserwartung von Lehrern. Zeitschrift für Pädagogik, 44, 192–214. https://doi.org/10.25656/01:3936 Schulz, P., Schlotz, W. & Becker, P. (2004). Trier Inventar zum chronischen Stress. Göttingen: Hogrefe Verlag.