Classification criteria for cervical radiculopathy: an international e-Delphi study

Background: Establishing a set of uniform classification criteria (CC) for cervical radiculopathy (CR) is required to aid future recruitment of homogenous populations to clinical trials. Objectives: To establish expert informed consensus on CC for CR. Design: A pre-defined four round e-Delphi study in accordance with the guidance on Conducting and Reporting Delphi Studies. Methods: Individuals with a background in physiotherapy who had authored two or more peer-reviewed publications on CR were invited to participate. The initial round asked opinions on CC for CR. Content analysis was performed on round one output and a list of discrete items were generated forming the round two survey. In rounds two to four, participants were asked to rate the level of importance of each item on a six-point Likert scale. Data were analysed descriptively using median, interquartile range and percentage agreement. Items reaching pre-defined consensus criteria were carried forward to the next round. Items remaining after the fourth round constituted expert consensus on CC for CR. Results: Twelve participants participated with one drop out. The final round identified one inclusion CC and 12 exclusion CC. The inclusion CC that remained achieved 82% agreement and was a cluster criterion consisting of radicular pain with arm pain worse than neck pain; paraesthesia or numbness and/or weakness and/or altered reflex; MRI confirmed nerve root compression compatible with clinical findings. Conclusions: The CC identified can be used to inform eligibility criteria for future CR trials although caution should be practiced as consensus on measurement tools requires further investigation.