A conceptual model of pain assessment for noncommunicative persons with dementia.

PURPOSE Our objectives are to present a conceptual model of the pain assessment process in persons with dementia and discuss methods for validating our model within this population. DESIGN AND METHODS This conceptual work is based on an integrative review and current pain theory, pain assessment research in demented and nondemented populations, and research on the science of self-report. RESULTS We present a multidimensional model of pain assessment that emphasizes the role of the external rater. Our model posits that a nociceptive stimulus leads to pain sensation, followed by pain perception, followed by the exhibition of external signs of pain by the patient, followed by an external rater's observation and interpretation of those external signs. Further, the model specifies the effects of nociceptive stimulus factors on pain sensation; patient-specific factors on pain perception; method-specific factors on external sign observation; and rater-specific factors on external sign interpretation. IMPLICATIONS Pain assessment in persons with dementia must go beyond a unidimensional model of pain assessment. This multidimensional model also directly addresses the challenges of using external ratings to assess pain in persons with dementia. Finally, we present clinical recommendations for applying the model to pain assessment endeavors and research recommendations for evaluating models of pain in this population.