Sustainable Development Goal 4 (SDG 4) emphasizes inclusive and equitable quality education for all. Information and communication technologies (ICTs) are considered a promising solution to advance equity, but the risk of exacerbating the digital divide remains. The digital divide is multifaceted, encompassing access to technology (first-order), digital competence (second-order), and the benefits derived from technology use (third-order). Despite improvements in ICT infrastructure, a persistent rural-urban digital divide in education persists, particularly concerning teachers' digital competence. This competence encompasses the skills, knowledge, and attitude required to effectively integrate ICT into teaching. Previous research highlights the positive impact of digital teaching competence on student empowerment but reveals a significant need for improvement, especially among rural teachers. This study addresses the research gap by investigating the factors influencing teachers' digital teaching competence, examining the existence of a rural-urban divide, and determining the relative importance of contributing factors. The study seeks to understand the determinants of this divide to inform policies and strategies for bridging it.

The literature review examines three key constructs: ICT attitude, ICT skills, and data literacy. Regarding ICT attitude, studies show mixed results, with some finding a positive correlation with digital teaching competence and others not. Geographic location is identified as a crucial variable, with urban teachers generally exhibiting more positive attitudes towards ICT. Regarding ICT skills, these are viewed as necessary for effective technology integration in teaching. Studies confirm a significant impact on digital teaching competence, particularly noting the more adequate technical environment in urban schools compared to rural settings. The review highlights the disparity in ICT skills between rural and urban teachers, exacerbated by limited resources in rural areas. Concerning data literacy, the review defines this as the ability to collect, analyze, interpret, and apply data in instructional contexts. While it is recognized as crucial for data-driven teaching decisions, existing research suggests a general lack of data literacy among teachers, particularly in rural areas. Few studies have directly compared rural and urban teachers' data literacy and its impact on digital teaching competence. Finally, the literature reveals a lack of research focusing on the determinants of the rural-urban divide in teachers' digital teaching competence. This study aims to fill these gaps.

This quantitative study employed a large-scale online survey of 11,784 K–12 teachers in Zhejiang province, China (5114 rural, 6670 urban). The survey instrument comprised demographic information and four subscales measuring ICT attitude, ICT skills, data literacy, and digital teaching competence (adopted from Lin et al., 2022). Each subscale used a 5-point Likert scale. The reliability and validity of the instrument were assessed using Cronbach's alpha (all > 0.8), average variance explained (AVE; all > 0.5), and confirmatory factor analysis (CFA). The CFA assessed model fit using various indices (RMSEA, NFI, TLI, CFI, IFI), all of which indicated acceptable model fit. Construct reliability and validity were further supported by evaluating composite reliability (CR) and AVE values. Convergent and discriminant validity were confirmed using factor loadings and square root AVEs. Hypotheses were tested using structural equation modeling (SEM) to explore relationships between the constructs and ANOVA to compare rural and urban teachers' scores. The Blinder-Oaxaca decomposition method was used to analyze the relative contributions of the observed factors (ICT attitude, ICT skills, data literacy, gender, and teaching experience) to the rural-urban divide in digital teaching competence. Bootstrapped standard errors with 500 replications were used to calculate statistical significance.

SEM analysis revealed significant positive correlations between ICT attitude, ICT skills, data literacy, and digital teaching competence (all p < 0.001). Specifically, ICT skills and data literacy showed the strongest effects on digital teaching competence. ANOVA indicated significant differences between rural and urban teachers in ICT attitude, ICT skills, data literacy, and digital teaching competence (all p < 0.001), with urban teachers consistently scoring higher. Blinder-Oaxaca decomposition revealed that 79.3% of the difference in digital teaching competence could be attributed to the differences in the observed characteristics of rural and urban teachers. Data literacy (43.1%) and ICT skills (25.9%) were the most significant factors contributing to the explained portion of the divide. The remaining 20.7% was attributed to unobserved characteristics or association effects.

The findings directly address the research questions. The study confirms that ICT attitude, ICT skills, and data literacy positively influence digital teaching competence, supporting previous research but highlighting the substantial effect of data literacy. The significant rural-urban divide in all four constructs confirms existing concerns about educational inequity. The decomposition analysis identifies data literacy and ICT skills as the most important drivers of the divide. The persistent gap, even in areas with improved ICT infrastructure, emphasizes the limitations of addressing the digital divide solely through technological investment. Improving teachers’ data literacy and ICT skills is crucial, particularly in rural areas, demanding targeted interventions and professional development programs. The study's findings provide critical insights for policymakers, school leaders, and teachers to address the digital divide and advance SDG 4.

This study makes significant contributions by providing empirical evidence on the rural-urban digital divide in teachers' digital teaching competence, identifying data literacy and ICT skills as key determinants. The findings highlight the need for comprehensive interventions that go beyond infrastructure development to focus on enhancing teachers' digital capabilities, specifically data literacy and ICT skills. Future research could investigate the long-term impacts of interventions aimed at bridging this divide, explore the third-order digital divide (outcome differences), and replicate the study in diverse geographical contexts to assess generalizability.

The study is limited to one province in China, potentially affecting generalizability. The findings may be more applicable to regions with relatively well-developed ICT infrastructure. The study focuses on the second-order digital divide and does not directly assess the third-order divide (outcomes). Future research could address these limitations by expanding the geographical scope, exploring contexts with less developed infrastructure, and examining the impact of the digital divide on student learning outcomes.