Abstract
BACKGROUND: Adolescents’ physical activity is related to characteristics of their neighbourhood environment. Understanding this relationship can help identify ways to promote this important health-related behaviour. The Neighbourhood Environment Walkability Scale for Youth (NEWS-Y) is the most prominent questionnaire to measure subjective perceptions on the neighbourhood environment that might have an influence on their physical activity. This study describes the development of the NEWS-Y for German-speaking adolescents (called NEWS-Y-G) and the evaluation of its reliability and validity. METHODS: The NEWS-Y-G was adapted and validated through a five-step process. First, the original NEWS-Y was translated into German using a back-translation technique. Participatory methods were then used to establish content validity by identifying environmental aspects specifically relevant to the German context. Third, ten cognitive interviews with adolescents were conducted for ensuring understandability before piloting the questionnaire with 587 adolescents. Of these, 249 participants completed the questionnaire twice, allowing for a test-retest reliability evaluation of subscales and individual items by using intraclass correlation coefficients (ICCs). Finally, construct validity was tested through correlations among subscales and associations with self-reported physical activity levels of participants. RESULTS: The NEWS-Y-G showed semantic equivalence with the original version. Five items were removed and twelve items were added, resulting in 74 items across the nine subscales: land use mix-diversity, recreational facilities, residential density, land use mix-access, street connectivity, walking/cycling facilities, aesthetics, traffic- and crime safety. The test-retest reliability of subscales (ICC range = 0.81–0.94) and individual items (ICC range = 0.32– 0.94) in the NEWS-Y-G was moderate to almost perfect. Moderate correlations were observed among several NEWS-Y-G subscales. Only two subscales – recreational facilities and aesthetics – showed statistically significant, albeit very weak, associations with self-reported physical activity (both ρ = 0.13, p < 0.01), while no significant associations were found for the other seven subscales (ρ = -0.08 to 0.03, p > 0.05). CONCLUSION: The NEWS-Y-G questionnaire demonstrated good test-retest reliability and provided preliminary evidence of validity. While this study supports its use in measuring subjective walkability among adolescents, further studies in German-speaking regions are needed to confirm its validity in relation to physical activity, accounting for different mobility types as well as gender and socioeconomic disparities. The NEWS-Y-G is a valuable tool for evaluating the neighbourhood environment’s impact on adolescents, providing results that can inform urban planning and research to promote physical activity. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-026-26590-3.