EFFICACY STUDIES OF OUR SPASMODIC DYSPHONIA TREATMENT CLINICS
Long Term Followup Clinic Results
August 2005 - November 2011
Does the program work? Preliminary Efficacy Data:
Original efficacy study from August 2005 – June 2007
There were a total of 38 participants seen in the Spasmodic Dysphonia Treatment clinic during this period. At 6 months, follow-up data was requested. 30 responded to the request, with 8 lost to follow-up. Each person completed a Voice Handicap Index (VHI-30) to compare to the initial one they completed before coming to the clinic and a brief questionnaire. Twenty seven of 30 completed the requested paperwork, with the remaining 3 sending brief emails. Three participants reported resuming botulinum toxin injections as their treatment of choice 1-8 months following the clinic. One participant tried botox once more without success before resuming the program. Two were able to tolerate smaller doses and continue voice exercises. In the three cases where botox was used primarily as the treatment of choice, VHI scores and questionnaires were not included in efficacy data. This was so that improvements were attributed to using voice rehabilitation without the possible added benefit of botulinum toxin.
A significant decrease in VHI scores was reported in 81% of participants. A change of 18 points on the VHI-30 has been validated to indicate significant change in perceived level of handicap rendered by voice function in three different areas. Average decrease in VHI was calculated for the July group to be 34 points. When asked to rate their level of voice improvement overall, 88% reported moderately to significantly improved voice production. Two people reported slight improvement and one reported a continued worsening of her voice following the clinic.
The least improvements correlated directly with the degree of compliance to the recommended program. In one case, however, difficulty was attributed to over-effort and subsequent emotional distress. Those who had not complied felt they may need to do so. Clearly, there is a pattern of improvement over time. Followup emails up to two years or more often indicate continued improvement in voice ease and production.
Second efficacy study from July 2007 – August 2008
There were a total of 37 participants seen in the clinic during this period. At 6 months, data was requested and received at 8 months, up to a year later. The Voice Handicap Index -30 was sent, as well as a brief questionnaire, which were the same documents used in the initial study. Twenty eight of the 37 provided feedback, with 12 lost to follow-up completely, and some sending brief email documentation about how they were progressing. Three participants reported resuming botox treatments and one had SLAD/R surgery followed by another vocal fold surgical procedure. I hope to gather data that indicates how the VHI changes with the use of botox and the techniques taught at the clinic combined. As in the first study, those scores were excluded in the efficacy report so that improvement noted here was a result of only use of the techniques learned at the clinic, using our Spasmodic Dysphonia Treatment methods.
A significant decrease in VHI scores was reported by 81%, with a range from 0 to 105 points decrease. The average decrease was 36 points. When asked to rate their level of improvement, 80% reported moderate to significant improvement in voice production. Four indicated no improvement in voice production and two indicated only slightly improved voice production. As was seen in the original study, compliance played a large role in failure to improve, but the percentages of improved voices and decreased level of handicap were comparable in the two groups.
Third efficacy study from January 2010– November 2011
There were a total of 37 participants seen in the clinic during this period. At 9 months, data was requested and received up to a year following the clinic. The Voice Handicap Index -30 was sent, as well as a brief questionnaire, which were the same documents used in the initial study. 34 of the 37 provided some of the requested documents. Four participants reported resuming botox treatments, so their data was excluded. However, several reported that they felt that the strategies they learned were helpful and enhanced their botox treatments.
A significant decrease in VHI-30 scores was reported by 95% of those who provided the scores who did not resume botox (N= 24). The average decrease was 36 points, with 18 points indicating a significant change statistically. When asked to rate their level of improvement, 83% reported moderate to significant improvement in voice production (N=24). Two indicated a worsening in voice production, and 3 indicated only slightly improved voice production. Nine reported moderate improvement (38%), 8 reported significant improvement (33%) and 3 reported normal voice production. The results of this study are similar to the first two studies, now spanning six years. Our Spasmodic Dysphonia treatment clinic is proving to be consistent in positive results.