Which of the following observation pain scale should the nurse use when assessing a non-verbal confused adult or a child when considering pain level?

For non-verbal or cognitively impaired patients, behavioral observation scales are the standard of care for pain assessment. The FLACC scale — which evaluates Facial expression, Leg movement, Activity, Crying, and Consolability — is one of the most widely validated tools for this population, including non-verbal confused adults and children. Behavioral indicators such as grimacing, guarding, restlessness, and vocalization provide objective data when the patient cannot self-report. Heart rate and respiratory rate changes can reflect pain but are non-specific and can be influenced by many other physiological factors such as fever, anxiety, or medication effects; they are not a standalone observation pain scale. Distraction techniques are a pain-management intervention, not an assessment tool, and using a patient's response to distraction as a gauge of pain level lacks standardization and reliability. Verbal self-report is considered the gold standard for pain assessment, but it is only applicable in patients who are communicative and cognitively intact — it cannot be used with the population described. Therefore, observing facial expressions, leg movement, activity level, and crying constitutes the appropriate behavioral pain assessment approach for this patient group.