Adaptation, Validity, and Reliability of the Respiratory Distress Observation Scale in Adult Palliative Care Patients: A Turkish Version

Any disorder affecting the components of the respiratory system directly impacts respiratory function, while impairments in other systems related to this system indirectly hinder respiratory function. This condition manifests in patients in various ways, including shortness of breath, air hunger, difficulty breathing, a sensation of suffocation, and chest tightness, influenced by physiological, cognitive, behavioral, and sociocultural factors. Under normal conditions, breathing is an unconscious physiological act that goes unnoticed. However, in the presence of the aforementioned disturbances, conscious awareness of the act of breathing emerges. According to the American Thoracic Society (ATS) report, dyspnea is defined as "a subjective experience of breathing discomfort that consists of qualitatively distinct sensations of varying intensity" and is acknowledged as a subjective sensation.

Dyspnea does not result from a single pathophysiological mechanism but may develop due to dysfunctions in multiple systems. Therefore, both identifying the underlying pathophysiology of dyspnea and measuring its presence and severity, given its subjective nature, are of great importance. Dyspnea assessment has been conducted using psychophysical methods and clinical scales. Psychophysical tests measure the perception of respiratory changes in response to externally applied loads, whereas clinical scales aim to determine the magnitude of the work contributing to breathlessness in patients. In addition to identifying the cause of dyspnea and initiating appropriate treatment, accurately measuring dyspnea severity plays a crucial role in planning both medical treatment and pulmonary rehabilitation interventions.

The assessment of dyspnea presence and severity is based on self-reported scales, which are considered partially objective. However, some patients-such as those with cognitive impairment, loss of consciousness, intubation, sedative medication use, or brain injury-are unable to provide self-reports. Monitoring dyspnea in patients unable to self-report has been reported as challenging. In clinical settings, healthcare professionals rely on respiratory rate and oxygen saturation levels to assess dyspnea severity and determine appropriate treatment strategies for such patients.

In Turkey, scales used to assess the presence and severity of dyspnea are based on self-reporting and are therefore not suitable for patients unable to communicate their symptoms. In 2008, Dr. Campbell developed the Respiratory Distress Observation Scale (RDOS) and demonstrated its reliability and validity in patients receiving palliative care-such as those with cancer, chronic obstructive pulmonary disease (COPD), heart failure, and pneumonia-who are unable to self-report their dyspnea. The RDOS consists of eight indicators related to dyspnea and takes less than five minutes to administer. Originally developed in English, the RDOS has been translated into Chinese and Italian. However, a Turkish version of the scale is needed. This study aims to examine the reliability and validity of the Turkish version of the RDOS.