The goal of this cross-sectional, qualitative study is to investigate whether physiotherapists screen for symptoms of anxiety and depression in patients with chronic musculoskeletal pain and to explore the facilitators and barriers related to these practices. The main questions aim to answer are:

• What are the current practices of physiotherapists in private practice for screening anxiety and depression among patients with chronic musculoskeletal pain?
• What are the facilitators and barriers influencing physiotherapists' screening and referral practices for mental health care?

Participants will:

• Take part in a semi-structured interview (online or in person).
• Be asked about their experiences, attitudes, and practices related to recognizing, screening, managing, and referring patients with anxiety and depression.
• Participants will share perspectives on barriers and facilitators to integrating mental health screening into physiotherapy.

Inclusion Criteria:

- Physiotherapists treating patients with chronic musculoskeletal conditions.

Purposive sampling was used to obtain:

• Varied clinical experience: Less than 5 years of practice and more than 5 years of practice.
• Varied exposure to mental health training: With and without specialized training in mental health.

Exclusion Criteria:

• None

Physiotherapists working in private practice settings in Belgium, with variation in gender, years of clinical experience, and prior mental health training.

Recruitment was conducted through two channels:

• Open-access contact list on the website of Axxon, the official Belgian physiotherapy professional association;
• Direct outreach to physiotherapists who had previously completed mental health-related training and consented to future research contact.