The Pittsburgh Sleep Quality Index (PSQI) is a 19-item self-report questionnaire used to assess sleep quality and disturbances over a one-month time interval. It evaluates seven 'component' scores: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction. Each component is scored from 0 to 3, yielding a global score ranging from 0 to 21. A total global score of greater than 5 is generally used to indicate poor sleep quality. Higher global scores represent poorer sleep quality and more significant sleep disturbances.

The Rheumatoid Arthritis Quality of Life (RAQOL) questionnaire is a disease-specific instrument designed to assess the quality of life in patients with rheumatoid arthritis using a needs-based model. It consists of 30 items with a binary response format (Yes/No). Each 'Yes' response is scored as 1, and each 'No' response is scored as 0. The total score ranges from 0 to 30, with higher scores representing a poorer quality of life and a greater negative impact of the disease on the individual's life. The scale focuses on various domains, including mood, social life, hobbies, everyday tasks, and physical contact.

The Chronic Illness Self-Management (CISM) scale is a 23-item tool designed to assess the self-management behaviors and perceptions of individuals living with chronic conditions. It consists of four subscales: Self-Stigma (7 items), Coping with Stigma (5 items), Healthcare Effectiveness (5 items), and Treatment Adherence (6 items). Each item is evaluated based on the patient's experience, providing a comprehensive measure of how well the individual manages the challenges associated with their illness. Higher scores in specific domains indicate better self-management capabilities and adaptation to the chronic condition.

Quantitative measurement of respiratory function will be performed using a calibrated spirometer in accordance with the ATS/ERS standardization protocols. FVC (expressed in Liters) will be recorded in a seated position to assess the presence and severity of extra-articular pulmonary involvement. The best of at least three acceptable maneuvers will be used for analysis.

Quantitative measurement of respiratory function assessed using a calibrated spirometer in accordance with the ATS/ERS standardization protocols. FEV1 measures the volume of air exhaled in the first second of the forceful exhalation.

The ratio of Forced Expiratory Volume in 1 second to Forced Vital Capacity, calculated from the spirometry maneuver to assess obstructive or restrictive pulmonary patterns.

Quantitative measurement of respiratory function assessed using a calibrated spirometer in accordance with the ATS/ERS standardization protocols. PEF measures the maximum speed of expiration.

Visual reaction time will be measured using the BlazePod device, a portable visual-cognitive technology designed to assess response speed to light stimuli. Simple and selective reaction time tasks will be performed where participants respond by touching or tapping the pod when it illuminates. To ensure reliability, each participant will complete multiple trials (typically 5-10), and the average reaction time in milliseconds will be calculated after excluding outliers. The testing procedure will be standardized regarding lighting conditions, distance, and participant positioning. This measurement serves as a neurocognitive performance indicator to evaluate the systemic and cognitive effects of the intervention.

A partial cost analysis will be conducted from a healthcare system perspective to evaluate the short-term economic impact of the digital intervention. Data on healthcare resource utilization-including the number of planned or unplanned rheumatology/internal medicine outpatient visits, emergency room admissions, and the number and duration of hospitalizations-will be collected retrospectively for the 8-week period using a structured 'Healthcare Utilization Questionnaire'. To calculate the total direct medical cost per patient, these frequency data will be multiplied by official unit costs derived from the current Social Security Institution (SGK) Health Implementation Communiqué (SUT) tariffs and supported by relevant cost-of-illness literature in Turkey. This analysis aims to provide preliminary empirical evidence on the cost-effectiveness of integrating mobile mind-body interventions into the routine management of Rheumatoid Arthritis.

The System Usability Scale will be administered only to participants in the intervention group to evaluate the usability, ease of use, and overall acceptability of the digital system used during the intervention. The SUS is a validated 10-item questionnaire scored on a 5-point Likert scale. Total scores range from 0 to 100, with higher scores indicating better perceived usability and user satisfaction with the system.