cVEMPs: a systematic review and meta-analysis.

OBJECTIVE A systematic literature review and meta-analysis was performed to determine the effect of stimulus type, SCM muscle activation method, transducer type, and method to control SCM muscle EMG level on response parameter values for 0.1-ms click-evoked and 500-Hz tone burst cVEMPs. A description of normative response values was attempted. DESIGN An electronic systematic literature review was performed to obtain normative cVEMP response data. Subsequently a meta-analysis was conducted to determine significant effects on cVEMP response parameters and to obtain norms. STUDY SAMPLE Scopus was used to identify reports containing normative data. Reports were selected based on inclusion and exclusion criteria determined beforehand. Weighted means were calculated and compared to identify significant effects and normative data. RESULTS Sixty-six reports were included in the systematic review. Stimulus type, SCM muscle activation method, transducer type, and method to control SCM muscle EMG level had significant effects on all response parameters. CONCLUSIONS Optimal stimulus and recording parameters suggested by previous research are confirmed by the current systematic review and meta-analysis and are suggested for clinical use. Response parameter values are influenced by variations in stimulus and recording parameters and normative response values are suggested as guideline for cVEMP interpretation.