Effectiveness of RMSSD-Based Adaptive Music Therapy (Skitii) in Reducing Treatment-Related Anxiety in Head and Neck Cancer Patients: Protocol for a Randomized Controlled Trial

Background: Head and neck cancer (HNC) patients experience clinically significant anxiety and depression in 65-85% of cases during active treatment. Current supportive care lacks personalized, real-time non-pharmacological interventions. Skitii is a novel HRV-adaptive music therapy system that uses continuous RMSSD (root mean square of successive differences) monitoring via a Polar H10 chest sensor to select music in real-time, targeting parasympathetic recovery (RMSSD >=30ms). Methods: This is a prospective, open-label, randomized controlled trial (1:1 allocation) at Yenepoya Medical College Hospital, Mangalore, India. Adults aged 18-75 years with confirmed head and neck cancer (any subsite