Validity, reliability and responsiveness to change of the French version of the drooling impact scale

Background:work still needs to be done to measure the impact of sialorrhea on quality of life and define the efficacy of different therapies. The Drooling Impact Scale showed good validity and sensitivity to change, especially after botulinum toxin injection. The aim of this study is to present its French translation and to explore its validity, reliability and responsiveness to change in a group of children with Cerebral Palsy. Methods:multicentre study at six rehabilitation centres in France. Children with Cerebral Palsy aged 4-18 years with sialorrhea problems were included (n = 55), either in a control group (n = 33) or in the intervention group (n = 22, with 3 drug treatment and 19 botulinum toxin injections). The French Drooling Impact Scale was administered twice, 1 month apart. Results:The French Drooling Impact Scale total score at inclusion was meanly 53.9 (Standard Deviation 11.9) in the stable control group and 66.0 (16.1) in the intervention group (p = 0.0058). The validity of the scale was established, as well as an adequate internal consistency (Cronbach's alpha = 0.71); correlations between each item and the total score were found between 0.5 and 0.71 except for item 5 (r = 0.38) and item 7 (0.41). The test-retest reliability in stable children was good (Lin coefficient = 0.83, bias correction factor = 0.92 and Pearson correlation coefficient = 0.89). There was a high responsiveness to change, mean change was -40.0 in the intervention group and -3.6 in the stable group (p < 0.0001), with Standard Error of Measurement = 2.6. Conclusion:the French Drooling Impact Scale has shown sufficient clinometric properties to be used now by clinicians or researchers.