Researchers examined provincial data for Shandong from 2014 through 2025, with 2020 treated as the reform-period reference point. The policy environment included Shandong’s vocational education innovation and development pilot zone, launched in 2020, amid a broader national restructuring of vocational education that began before the designated intervention year. The central interrupted time-series regression estimated whether the aggregate transition gap changed immediately around 2020 and whether its subsequent trajectory changed. The policy coefficient was −2.397, with p = 0.050, while the post-intervention trend coefficient was −0.053, with p = 0.864.

The study’s measure of educational disengagement was not a direct count of dropouts or an assessment of students’ psychological withdrawal from school. It was calculated as the difference between the number of junior-high graduates reported in Shandong and the combined number entering general senior secondary and secondary vocational schools, divided by the number of graduates. For example, 1.053 million graduates and 855,100 entrants produced a transition gap of 18.79% in 2019. That percentage can also reflect delayed enrollment, migration, cross-regional enrollment, alternative training pathways and differences in reporting conventions.

Across the full period, the measured gap rose from 17.77% in 2014 to a high of 23.74% in 2018, fell to 14.95% in 2020, and then remained near 18% through 2025. The average was 20.55% before the reform reference point and 17.81% after it. The regression therefore suggested a short-term level shift rather than a continuing structural decline. The study describes the reform as associated with improved access to the included upper-secondary pathways, but it does not establish that the policy itself produced the change or that students’ individual engagement improved.

Sensitivity analyses complicated the interpretation of the headline result. When 2018 was used as a placebo intervention year, the policy coefficient was negative but not statistically significant. When 2019 was substituted, however, the coefficient was −2.817 with p < 0.01, indicating that an intervention-like decline was already detectable before the formal 2020 reference point. A leave-one-year-out analysis retained negative coefficients in every tested specification, but significance changed: the estimate was −1.853 with p = 0.091 when 2018 was removed, −1.331 with p = 0.249 when 2020 was removed, and −2.941 with p = 0.017 when 2021 was removed.

The authors said the 2019 placebo result suggests that the transition gap may have begun declining during policy preparation, implementation or other earlier changes, making 2020 better understood as a period of institutional consolidation or intensification than as a clean policy shock. A Durbin–Watson statistic of 2.22 suggested that the baseline residuals did not exhibit substantial first-order positive or negative autocorrelation. Even so, the model’s 12 observations—six before and six after 2020—limited its statistical power and made estimates sensitive to individual years.

Juvenile justice involvement, measured as the annual number of juveniles involved in prosecution procedures, followed a different pattern. The count averaged 2,161 before 2020 and 3,651 afterward, an increase of 40.81%, while the educational transition gap declined by an average of 2.74 percentage points. Justice involvement peaked in 2022, two to three years after the gap reached its minimum in 2020. That timing was descriptively compatible with a possible delayed relationship, but it was not statistical evidence of one or proof of a particular lag.

Exploratory regression models found no significant association between aggregate disengagement and juvenile justice involvement either in the same year or with a one-year lag. The contemporaneous coefficient was 0.227 with p = 0.436, and the lagged coefficient was 0.139 with p = 0.667. The concurrent model had an R² of 0.682, compared with 0.663 for the lagged model, although those values describe the models as a whole rather than a significant education–justice relationship. The study therefore did not support its exploratory question at the provincial annual level.

Several limitations prevent the results from being read as evidence that educational reform reduces offending or that education and justice involvement are unrelated. Juvenile justice counts may reflect not only underlying behavior but also prosecutorial practices, reporting patterns and policies emphasizing reduced use of arrest, cautious prosecution and limited detention. Provincial annual data cannot observe school attachment, peer influence, family conditions, employment expectations or social integration, and they cannot identify which students entered the upper-secondary pathways or whether educational trajectories and justice involvement influenced each other. The findings also come from one province with distinctive policy and socioeconomic conditions, limiting generalization. More frequent and longer time series, comparison regions and individual- or school-level longitudinal data would be needed to determine whether any education–justice relationship emerges over longer periods.

Subject of Research: Exploratory analysis of upper-secondary education reform, educational transition gaps, and juvenile justice involvement in Shandong Province, China.

Article Title: Upper secondary education policy adjustment, educational disengagement and juvenile justice involvement: an interrupted time-series analysis in Shandong province, China, 2014–2025

Article References: Li, B. (2026). Upper secondary education policy adjustment, educational disengagement and juvenile justice involvement: an interrupted time-series analysis in Shandong province, China, 2014–2025. Frontiers in Education, 11, Article 1955861. https://doi.org/10.3389/feduc.2026.1955861

Image Credits: AI Generated

DOI: 10.3389/feduc.2026.1955861

Keywords: Shandong Province, upper-secondary education, vocational education reform, educational disengagement, interrupted time-series, juvenile justice, policy evaluation, China, Upper, secondary, education, policy