The goal of this observational study is to understand the burden and determinants of tobacco use and air pollution (AP) exposure among mid- to late adolescents in Greece, the Kyrgyz Republic, Pakistan, Romania, and Uganda. This context-specific knowledge will be crucial for selecting, adapting, and implementing preventive interventions in the next phase of the project.

The main questions the investigators aim to answer are:

• What is the perceived burden of tobacco use and AP exposure among adolescents?
• What are the contextual drivers and behavioral determinants contributing to (prevention of) these risk factors?
• How do the dynamics between stakeholders influence prevention efforts?

In this study, data will be collected through interviews, focus group discussions, photovoice, document analysis, observations, personal exposure monitoring, and questionnaires.

Inclusion Criteria:

• Adolescents: mid- to late-adolescents (14 to 21 years) within the target population;
• Family members: relatives in the first or second degree of (not necessarily participating) adolescents;
• Providers: any relevant stakeholder that is connected to adolescents through profession (e.g. school teacher, youth worker) and/or providers of (public) healthcare;
• Stakeholders: any relevant stakeholder with either a specific expertise, in-depth knowledge or overall overview on the subject, and in direct contact with the community (e.g. community member/leader, policy maker). Due to the community- and individual-level focus of this research, individuals associated with the tobacco industry are deliberately not included as stakeholders.

Exclusion Criteria:

- People living outside the target area or not in direct contact with the target population.

This study will be performed in Greece, Romania, the Kyrgyz Republic, Pakistan and Uganda. These countries all have a high NCD burden but differ largely in contextual factors like population size (from 6.7 million in the Kyrgyz Republic to 231 million in Pakistan), population age (median age of 15.9 years in Uganda, up to 44.7 years in Greece), income classification (low in Uganda, low-middle in Pakistan and the Kyrgyz Republic, and high in Greece and Romania) and life expectancy (62.9 years in Uganda to 81.1 years in Greece).

All countries will have an urban area as starting point (for logistical reasons and due to high prevalence of the vast majority of risk factors in urban areas), with either a peri-urban or rural community as second investigation site. Genders will equally be included in the situational analysis.