The Evaluation Indexes Suitable for Nonhuman Primates can be Extracted from Clinical Consciousness Disorder Assessment Scales: A Hypothesis

Abstract

Background: Currently, case studies or clinical trials in different patient populations remain the main resource underlying the understanding of disorder of consciousness (DoC). This provides a low efficacy for the derivation of data and the implementation of associated controlled experimental designs. Preclinical models provide precise controls, reduced variability, rich data output and limited ethical complexity. Nonhuman primates are suitable model animals for disorders of consciousness due to their brain structure being very similar to that of humans. Behavioral tests remain the primary standard for assessing the consciousness status of humans. However, there is currently no behavioral assessment scale available for evaluation of the state of consciousness disorder in nonhuman primates. This presents a significant challenge for the establishment of different models of consciousness disorder. Therefore, there is considerable motivation to focus on the development of a proper tool for assessment of the state of consciousness associated with nonhuman primate models that are based on clinically common consciousness assessment scales.

Methods: It is assumed that the Delphi and level analysis methods based on clinical consciousness disorder assessment scales may provide an effective way to select and include assessment indexes for levels of consciousness in nonhuman primates.

Results: 8 first-level indicators with 41 second-level indexes were selected preliminary as a pool of evaluation entries of state of consciousness of nonhuman primates.

Conclusions: It may be practicable to extract appropriate indicators for non-human primates from the clinical consciousness disorder assessment scales. Besides, a combination of Delphi method, behavioral analysis, electroencephalography, neuroimaging (such as positron emission tomography-computed tomography) and functional magnetic resonance imaging is necessary to test the reliability and validity of the novel scale reported here.

Keywords: animal models; assessment scale; disorders of consciousness; nonhuman primates.