Assessment of reliability and validity of the mental chronometry task based on the box and block test in multiple sclerosis patients

Motor imagery (MI) is the visualization of action without its overt performance.One of the measures of explicit MI is mental chronometry whichhas been applied to multiple sclerosis (MS)patients; nonetheless, thereliability and validity of this tool has been never confirmed.

Therefore, the present study aimed to assess the reliability and validity of mental chronometry in MS patients.

A number of 60 MS patients who met the inclusion criteria were included in the present study via the census method.Thereafter, 20 MS patients were tested via mental chronometry based on the box and blocktest, as well as kinesthetic and visual imagery questionnaire-20 (KVIQ-20) in two sessions with a 10-day interval. Intra-classcorrelation coefficients (ICCs) were calculatedto determinethe test-retest reliability of mental chronometry. Pearson’s correlation analysiswas used to evaluate criterionvalidity with the KVIQ-20.

Thetest-retest reliability forthementalchronometry wasgood(ICCs:visual analogue scale=0.88,mean execution andmotor imagery absolutedifference= 0.75,imagery duration=0.91, and execution duration=0.97). Moreover, the concurrent validity between the visual analogue scale of mental chronometry and KVIQ-20 was good.

As evidenced by the results of the present study, the mental chronometry based on box and block is a reliable and valid tool for the assessment of motor imagery inMS patients.