Relevance & Research Question Digitalization can contribute to the shift towards a sustainable circular economy (CE). Digitalization not only refines business processes but also emphasizes waste curtailment, prolonging product life, and slashing transaction costs. However, fully leveraging this integration presents challenges, with clear gaps hindering the fluid adoption of digital-backed circular business models. Despite its significance, there's a dearth of comprehensive literature on digitalization's potential and challenges. This research aims to explore the main benefits and obstacles of applying digitalization in CE business models in Ukraine, focusing on identifying opportunities and challenges and finding ways to overcome these hurdles.

Methods & Data The study involved interviews with business representatives, researchers, NGOs, and students (a total of 36 participants) during the thematic training course according to the Erasmus+ program in an online format in Ukraine. One of the activities during the training course was finding answers to four questions relevant to the research aim in small groups for 40 minutes for 7-8 participants.

Results I identified challenges related to the integration of circular principles into existing business models, data ownership, data sharing, data integration, collaboration, and competence requirements. The post-war rebuilding and modernizing of industries towards sustainability, visualization, and innovation in product design, enhancement in resource efficiency, and optimization of logistics process collaboration with stakeholders and implementation of digital technologies were noted as main opportunities in adopting business models based on CE in the Ukrainian perspective.

Added Value This research uncovered less recognized or previously unexplored prospects linked to digitalization in the context of transitioning to a CE. One of the new opportunities is virtualization in business models can influence on reduce costs, conserve resources, and provide reliable data. The research underscores the significant role of digitalization in enabling the transition towards a circular economy in Ukraine's business sector. While there are considerable opportunities for innovation and modernization, the challenges of integration, collaboration, data management, and skill gaps cannot be overlooked. Addressing these challenges through targeted educational programs, strategic partnerships, and supportive policies will be pivotal in harnessing the full potential of digitalization in advancing circular economy models.

Relevance & Research Question Due to the overall presence of smartphones and the ease of use of these devices, understanding the impact of device choice on survey data quality is becoming increasingly important. This study delves into the intricacies of a community survey conducted through both a paper flyer in the mail box and face-to-face recruitment by students. The primary objective is to explore the correlation between demographic characteristics and the selection of devices for survey completion. Additionally, the study investigates variations in data quality, measured through completion time and response patterns such as straightlining, acquiescence bias, and midpoint responding.

Methods & Data The target population consisted of all 5475 residents of a neighborhood in Groningen, living in 4035 households. In December 2023, a total of 3500 flyers were distributed to every address that was recognized as a home address with a separate mail box. Subsequently, students visited homes, encouraging residents to participate in the survey. Students referred to the flyer delivered in the mail box, but presented residents with a new flyer in case the flyer got lost. Participants were given the option to engage via a QR code (i.e., completion on a smartphone) or a concise URL (i.e., completion on a pc), with a sweet incentive of a cake as compensation for their contribution.

Results Within two weeks, 605 residents completed the questionnaire, resulting in a response rate of 17%. Notably, the QR code emerged as the preferred method for survey completion, with 85% opting for it, while the URL accounted for 15%. Interestingly, both students and individuals aged over 65 demonstrated a higher likelihood of using the URL. However, no significant associations were uncovered between completion time and the type of device chosen for survey participation.

Added Value This study boasts a unique inclusion of all addresses within a single neighborhood in the recruitment sample, transforming it into a comprehensive population survey. In addition, in this study door-to-door recruitment and use of flyers that respondents use to decide their type of device distinguishes this study from earlier work.