Social Skills and Cognitive Training to Support Work-Related Skills and Job Placement in a Group of Autistic Adults : Effectiveness of a Neuropsychological and Social Skills Intervention: A Case Series Study on a Pilot Program.

Autistic people may have difficulties in finding and keeping a job. Studies highlight that only 34% of autistic people are employed compared to 54% of people with disability. 58% of people with ASD have never had a job. Social cognition and cognitive strains may also have a significant impact on working life. The primary goal of our project is supporting autistic people through a training program focused on neuropsychological and social skills training to improve participant' job skills. Through an Individual Placement and Support model the project involved various Partners to guide, identify skills and interests, provide cognitive and psychological support for autistic people. Results highlighted neuropsychological training efficacy, especially in inhibitory control and good rate of employment status at the end of the project. Findings are encouraging and underline the importance of a multidisciplinary approach to support autistic people in their work life considering their expectations, needs and inclinations.

Basic clinical features do not predict dopamine transporter binding in idiopathic REM behavior disorder.

REM sleep behavior disorder (RBD) is strongly associated with development of Parkinson's Disease and other α-synuclein-related disorders. Dopamine transporter (DAT) binding deficit predicts conversion to α-synuclein-related disorders in individuals with RBD. In turn, identifying which individuals with RBD have the highest likelihood of having abnormal DAT binding would be useful. The objective of this analysis was to examine if there are basic clinical predictors of DAT deficit in RBD. Participants referred for inclusion in the RBD cohort of the Parkinson Progression Markers Initiative were included. Assessments at the screening visit including DAT SPECT imaging, physical examination, cognitive function screen, and questionnaire-based non-motor assessment. The group with DAT binding deficit (n = 49) was compared to those without (n = 26). There were no significant differences in demographic or clinical features between the two groups. When recruiting RBD cohorts enriched for high risk of neurodegenerative disorders, our data support the need for objective biomarker assessments.

Cognitive performance of GBA mutation carriers with early-onset PD: the CORE-PD study.

OBJECTIVE: To assess the cognitive phenotype of glucocerebrosidase (GBA) mutation carriers with early-onset Parkinson disease (PD). METHODS: We administered a neuropsychological battery and the University of Pennsylvania Smell Identification Test (UPSIT) to participants in the CORE-PD study who were tested for mutations in PARKIN, LRRK2, and GBA. Participants included 33 GBA mutation carriers and 60 noncarriers of any genetic mutation. Primary analyses were performed on 26 GBA heterozygous mutation carriers without additional mutations and 39 age- and PD duration-matched noncarriers. Five cognitive domains, psychomotor speed, attention, memory, visuospatial function, and executive function, were created from transformed z scores of individual neuropsychological tests. Clinical diagnoses (normal, mild cognitive impairment [MCI], dementia) were assigned blind to genotype based on neuropsychological performance and functional impairment as assessed by the Clinical Dementia Rating (CDR) score. The association between GBA mutation status and neuropsychological performance, CDR, and clinical diagnoses was assessed. RESULTS: Demographics, UPSIT, and Unified Parkinson's Disease Rating Scale-III performance did not differ between GBA carriers and noncarriers. GBA mutation carriers performed more poorly than noncarriers on the Mini-Mental State Examination (p = 0.035), and on the memory (p = 0.017) and visuospatial (p = 0.028) domains. The most prominent differences were observed in nonverbal memory performance (p < 0.001). Carriers were more likely to receive scores of 0.5 or higher on the CDR (p < 0.001), and a clinical diagnosis of either MCI or dementia (p = 0.004). CONCLUSION: GBA mutation status may be an independent risk factor for cognitive impairment in patients with PD.

The relation between depression and parkin genotype: the CORE-PD study.

BACKGROUND: Mutations in parkin are a known genetic risk factor for early onset Parkinson's disease (EOPD) but their role in non-motor manifestations is not well established. Genetic factors for depression are similarly not well characterized. We investigate the role of parkin mutations in depression among those with EOPD and their relatives. METHODS: We collected psychiatric information using the Patient Health Questionnaire and Beck Depression Inventory II on 328 genotyped individuals including 88 probands with early onset PD (41 with parkin mutations, 47 without) and 240 first and second-degree relatives without PD. RESULTS: Genotype was not associated with depression risk among probands. Among unaffected relatives of EOPD cases, only compound heterozygotes (n = 4), and not heterozygotes, had significantly increased risk of depressed mood (OR = 14.1; 95% CI 1.2-163.4), moderate to severe depression (OR = 17.8; 95% CI 1.0-332.0), depression (score ≥ 15) on the Beck Depression Inventory II (BDI-II) (OR = 51.9; 95% CI 4.1-657.4), and BDI-II total depression score (ß = 8.4; 95% CI 2.4-11.3) compared to those without parkin mutations. CONCLUSIONS: Relatives of EOPD cases with compound heterozygous mutations and without diagnosed PD may have a higher risk of depression compared to relatives without parkin mutations. These findings support evidence of a genetic contribution to depression and may extend the phenotypic spectrum of parkin mutations to include non-motor manifestations that precede the development of PD.

Olfaction in Parkin heterozygotes and compound heterozygotes: the CORE-PD study.

BACKGROUND: While Parkinson disease (PD) is consistently associated with impaired olfaction, one study reported better olfaction among Parkin mutation carriers than noncarriers. Whether olfaction differs between Parkin mutation heterozygotes and carriers of 2 Parkin mutations (compound heterozygotes) is unknown. OBJECTIVE: To assess the relationship between Parkin genotype and olfaction in PD probands and their unaffected relatives. METHODS: We administered the University of Pennsylvania Smell Identification Test (UPSIT) to 44 probands in the Consortium on Risk for Early-Onset Parkinson Disease study with PD onset ≤50 years (10 Parkin mutation heterozygotes, 9 compound heterozygotes, 25 noncarriers) and 80 of their family members (18 heterozygotes, 2 compound heterozygotes, 60 noncarriers). In the probands, linear regression was used to assess the association between UPSIT score (outcome) and Parkin genotype (predictor), adjusting for covariates. Among family members without PD, we compared UPSIT performance in heterozygotes vs noncarriers using generalized estimating equations, adjusting for family membership, age, gender, and smoking. RESULTS: Among probands with PD, compound heterozygotes had higher UPSIT scores (31.9) than heterozygotes (20.1) or noncarriers (19.9) (p < 0.001). These differences persisted after adjustment for age, gender, disease duration, and smoking. Among relatives without PD, UPSIT performance was similar in heterozygotes (32.5) vs noncarriers (32.4), and better than in heterozygotes with PD (p = 0.001). CONCLUSION: Olfaction is significantly reduced among Parkin mutation heterozygotes with PD but not among their heterozygous relatives without PD. Compound heterozygotes with PD have olfaction within the normal range. Further research is required to assess whether these findings reflect different neuropathology in Parkin mutation heterozygotes and compound heterozygotes.

High-resolution diffusion tensor imaging in the substantia nigra of de novo Parkinson disease.

BACKGROUND: In the midbrain of patients with Parkinson disease (PD), there is a selective loss of dopaminergic neurons in the ventrolateral and caudal substantia nigra (SN). In a mouse model of PD, investigators have administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and found that measures derived using diffusion tensor imaging (DTI) were correlated with the number of dopamine neurons lost following intoxication. METHODS: Twenty-eight subjects (14 with early stage, untreated PD and 14 age- and gender-matched controls) were studied with a high-resolution DTI protocol at 3 Tesla using an eight-channel phase array coil and parallel imaging to study specific segments of degeneration in the SN. Regions of interest were drawn in the rostral, middle, and caudal SN by two blinded and independent raters. RESULTS: Fractional anisotropy (FA) was reduced in the SN of subjects with PD compared with controls (p < 0.001). Post hoc analysis identified that reduced FA for patients with PD was greater in the caudal compared with the rostral region of interest (p < 0.00001). A receiver operator characteristic analysis in the caudal SN revealed that sensitivity and specificity were 100% for distinguishing patients with PD from healthy subjects. Findings were consistent across both raters. CONCLUSIONS: These findings provide evidence that high resolution diffusion tensor imaging in the substantia nigra distinguishes early stage, de novo patients with Parkinson disease (PD) from healthy individuals on a patient by patient basis and has the potential to serve as a noninvasive early biomarker for PD.

Fatigue in levodopa-naive subjects with Parkinson disease.

BACKGROUND: Fatigue is a common complaint in Parkinson disease (PD). We investigated fatigue in a cohort of previously untreated patients with early PD enrolled in the Earlier vs Later Levodopa (ELLDOPA) clinical trial. METHODS: A total of 361 patients were enrolled in the randomized, double-blind, placebo-controlled ELLDOPA trial and assigned to receive placebo or carbidopa-levodopa 37.5/150 mg, 75/300 mg, or 150/600 mg daily for 40 weeks, followed by a 2-week medication washout period. Subjects who scored >4 on the Fatigue Severity Scale were classified as fatigued. PD severity was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn-Yahr scale, and Schwab-England Activities of Daily Living Scale. A subgroup of subjects underwent [(123)I]-beta-CIT SPECT to measure striatal dopamine transporter density. RESULTS: Of the 349 ELLDOPA subjects who completed fatigue measures, 128 were classified as fatigued at baseline. The fatigued group was significantly more impaired neurologically (UPDRS, all subscales and Hoehn and Yahr staging) and functionally (Schwab-England Scale) but no significant differences were observed in beta-CIT measurements between the two groups. Analysis of covariance showed a greater increase in fatigue score from baseline to the end of the 2-week washout in the placebo group (0.75 points) than in the three groups receiving levodopa (increases of 0.30 [150 mg/day], 0.36 [300 mg/day], and 0.33 [600 mg/day]; p = 0.03 for heterogeneity). CONCLUSIONS: Fatigue is a frequent symptom in early, untreated, non-depressed patients with Parkinson disease (PD), affecting over 1/3 of the patients in this cohort at baseline and 50% by week 42. Fatigue was associated with the severity of PD, and progressed less in patients treated with levodopa.

Assessment: Botulinum neurotoxin for the treatment of movement disorders (an evidence-based review): report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology.

OBJECTIVE: To perform an evidence-based review of the safety and efficacy of botulinum neurotoxin (BoNT) in the treatment of movement disorders. METHODS: A literature search was performed including MEDLINE and Current Contents for therapeutic articles relevant to BoNT and selected movement disorders. Authors reviewed, abstracted, and classified articles based on American Academy of Neurology criteria (Class I-IV). RESULTS: The highest quality literature available for the respective indications was as follows: blepharospasm (two Class II studies); hemifacial spasm (one Class II and one Class III study); cervical dystonia (seven Class I studies); focal upper extremity dystonia (one Class I and three Class II studies); focal lower extremity dystonia (one Class II study); laryngeal dystonia (one Class I study); motor tics (one Class II study); and upper extremity essential tremor (two Class II studies). RECOMMENDATIONS: Botulinum neurotoxin should be offered as a treatment option for the treatment of cervical dystonia (Level A), may be offered for blepharospasm, focal upper extremity dystonia, adductor laryngeal dystonia, and upper extremity essential tremor (Level B), and may be considered for hemifacial spasm, focal lower limb dystonia, and motor tics (Level C). While clinicians' practice may suggest stronger recommendations in some of these indications, evidence-based conclusions are limited by the availability of data.

The treatment of cervical dystonia with botulinum toxins.

Botulinum neurotoxin (BoNT) treatment has been used extensively for the treatment of cervical dystonia. There are three established brands and two serotypes of BoNT commercially available in most of the world, and several additional brands are available in selected geographic regions. In most controlled studies, there is significant improvement following treatment for head posture, pain and disability. The common side effects of treatment include dysphagia, dry mouth, and neck weakness. Each brand and serotype is pharmacologically distinct. The dosing of each type differs, and no simple dose equivalency has been established. With repeated treatment, the development of immunoresistance is observed in a percentage of patients. However, it is likely that each brand and serotype may differ in immunogenic potential and occurrence of secondary unresponsiveness, an issue that is currently under active investigation.

Clinico-immunologic aspects of botulinum toxin type B treatment of cervical dystonia.

In this multicenter study of 100 patients with cervical dystonia, we examined the immunogenicity of botulinum toxin type B (BTX-B) and correlated the clinical response with the presence of blocking antibodies (Abs) using a novel mouse protection assay. One-third of the patients who were negative for BTX-B Abs at baseline became positive for BTX-B Abs at last visit. Thus, the high antigenicity of BTX-B limits its long-term efficacy.

Sleep disturbances and excessive daytime sleepiness in Parkinson disease: an overview.

Sleep disturbances are frequent in Parkinson disease. These disorders can be broadly categorized into those that involve nocturnal sleep and excessive daytime sleepiness. The disorders that are often observed during the night in PD include sleep fragmentation that may be due to recurrent PD symptoms, sleep apnea, Restless Leg Syndrome/ periodic limb movements and REM sleep behavior disorder. Excessive daytime sleepiness is also a common occurrence in PD. EDS can arise from several etiologies, and patients may have more than one etiology responsible. The causes of EDS include nocturnal sleep disorder with sleep deprivation and resulting daytime somnolence, the effect of drugs used to treat PD, and possibly neurodegeneration of central sleep/wake areas. Appropriate diagnosis of the sleep disturbance affecting a PD patient can lead to specific treatments that can consolidate nocturnal sleep and enhance daytime alertness.

Treatment of cervical dystonia with botulinum toxins.

Botulinum toxin (BoNT) treatment has been used extensively for the treatment of cervical dystonia. In most studies, there is significant improvement following treatment for head posture and pain. The common side effects following treatment include dysphagia, dry mouth, and neck weakness. There are five brands and two serotypes of BoNT available. The dosing of each serotype and brand differs. Perhaps more importantly, each brand and serotype may differ in immunogenic potential and occurrence of secondary unresponsiveness, an issue that is currently under active investigation. Although many aspects of the technique of injection have not been adequately studied, general guidelines are available.

Comparison of botulinum toxin serotypes A and B for the treatment of cervical dystonia.

OBJECTIVE: To directly compare two serotypes of botulinum toxin (BoNTA and BoNTB) in cervical dystonia (CD) using a randomized, double-blind, parallel-arm study design. METHODS: Subjects with CD who had a previous response from BoNTA were randomly assigned to BoNTA or BoNTB and evaluated in a blinded fashion at baseline, 4 weeks, 8 weeks, and 2-week intervals thereafter until loss of 80% of clinical effect or completion of 20 weeks of observation. CD severity was measured with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), and adverse events were assessed by structured interview. Statistical analysis included Wilcoxon rank sum test, log rank tests, and Kaplan-Meier survival curves for duration of effect. RESULTS: A total of 139 subjects (BoNTA, n = 74; BoNTB, n = 65) were randomized at 19 study sites. Improvement in TWSTRS score was found at 4 weeks after injection and did not differ between serotypes. Dysphagia and dry mouth were more frequent with BoNTB (dysphagia: BoNTA 19% vs BoNTB 48%, p = 0.0005; dry mouth (BoNTA 41% vs BoNTB 80%, p < 0.0001). In clinical responders, BoNT A had a modestly longer duration of benefit (BoNTA 14 weeks, BoNTB 12.1 weeks, p = 0.033). CONCLUSION: Both serotypes of botulinum toxin (BoNTA and BoNTB) had equivalent benefit in subjects with cervical dystonia at 4 weeks. BoNTA had fewer adverse events and a marginally longer duration of effect in subjects showing a clinical response.

Muscle activation patterns in point-to-point and reversal movements in healthy, older subjects and in subjects with Parkinson's disease.

When young, healthy subjects perform rapid point-to-point and reversal movements over a range of distances, the patterns of muscle activation associated with accelerating the limb toward the target are modulated in the same way for both movement tasks. Differences in patterns of muscle activation for these two movement types are not observed until the deceleration phase of the movements. In this study, we first test the hypothesis that healthy, older subjects and subjects with Parkinson's disease will modulate the pattern of muscle activation in the same way during the acceleration phase of point-to-point and reversal elbow movements. Second, we test the hypothesis that healthy, older subjects and subjects with Parkinson's disease exhibit the same relationship in muscle activation patterns between the two movement types that have been observed for the young in the deceleration phase of the movements. Subjects performed point-to-point and reversal movements initiated in the direction of flexion over three distances (36, 54 and 72 degrees) "as fast as possible". Angle, velocity, acceleration and surface EMGs from biceps and triceps were recorded. With respect to the first hypothesis, the EMG, kinetic, and kinematic measures related to the acceleration phase of the movements were modulated in the same way for both movement types in the healthy older subjects. In the Parkinson's disease group, the kinematic and kinetic measures during the acceleration phase of the movements were the same in both movement types; however, the flexor and extensor EMG activation was smaller during reversal movements than during point-to-point movements. With respect to the second hypothesis, in contrast to that found in young subjects, in healthy older subjects, there was no significant difference between the movement types in the flexor EMG activity immediately after the time of peak velocity. This difference between younger and older subjects may be attributed to the fact that older subjects perform both movement types more slowly than do younger subjects. Although subjects with Parkinson's disease also move slowly, the flexor EMG shuts off more abruptly and more completely just after the time of peak velocity during reversal movements than during point-to-point movements. These results show that (1) for healthy subjects, when the task requirements are the same for the two movement types (acceleration phase), muscle activation patterns are modulated in the same way, and (2) both age and disease alter the relationship of muscle activation, kinetics and kinematics between point-to-point and reversal movements.

Longitudinal outcome of Parkinson's disease patients with psychosis.

OBJECTIVES: To examine the long-term outcome of PD patients with psychosis requiring antipsychotic therapy; to explore predictors of mortality, nursing home placement, dementia, and persistent psychosis; and to compare outcomes of those with persistent psychosis vs those whose psychosis resolved. METHODS: Baseline data available from 59 patients enrolled in the PSYCLOPS (PSychosis and CLOzapine in PD Study) trial included age, age at onset of PD, duration of PD and psychosis, character of psychosis, medications, living setting, and scores for Mini-Mental State Examination (MMSE), Unified Parkinson's Disease Rating Scale, Hoehn and Yahr Scale, and Clinical Global Impression Scale. Longitudinal data were collected 26 months later regarding four outcomes: death, nursing home placement, diagnosis of dementia, and persistence of psychosis. Logistic regression was used to explore whether any baseline characteristics were associated with an increased likelihood of one of these outcomes. RESULTS: At baseline, 56% of patients had an MMSE score of <25, 12% were in a nursing home, 95% had hallucinations, and 60% had paranoia. On follow-up, 25% were dead, nursing home placement occurred in 42%, psychosis was persistent in 69%, and dementia was diagnosed in 68%. Select baseline characteristics predicted individual outcomes: Nursing home placement was associated with the presence of paranoia and older age; persistent psychosis was associated with younger age at onset of PD and longer disease duration; dementia was associated with older age at PD onset and lower initial MMSE score; no characteristics predicted death. Whether psychosis persisted or not had no significant effect on the development of the other three outcomes. The prevalence of hallucinations at follow-up was not different between groups currently receiving antipsychotics vs those on no treatment. CONCLUSIONS: Psychosis in PD requiring antipsychotic therapy is frequently associated with death, nursing home placement, development and progression of dementia, and persistence of psychosis. Still, it appears the prognosis has improved with atypical antipsychotic therapy based on the finding that 28% of NH patients died within 2 years compared with 100% in a previous study done prior to availability of this treatment.

Randomized, double-blind trial of glial cell line-derived neurotrophic factor (GDNF) in PD.

OBJECTIVE: To assess the safety, tolerability, and biological activity of glial cell line-derived neurotrophic factor (GDNF) administered by an implanted intracerebroventricular (ICV) catheter and access port in advanced PD. BACKGROUND: GDNF is a peptide that promotes survival of dopamine neurons. It improved 6-OHDA- or MPTP-induced behavioral deficits in rodents and monkeys. METHODS: A multicenter, randomized, double-blind, placebo-controlled, sequential cohort study compared the effects of monthly ICV administration of placebo and 25, 75, 150, 300, and 500 to 4,000 microg of GDNF in 50 subjects with PD for 8 months. An open-label study extended exposure up to an additional 20 months and maximum single doses of up to 4,000 microg in 16 subjects. Laboratory testing, adverse events (AE), and Unified Parkinson's Disease Rating Scale (UPDRS) scoring were obtained at 1- to 4-week intervals throughout the studies. RESULTS: Twelve subjects received placebo and seven or eight subjects were assigned to each of the other GDNF dose groups. "On" and "off" total and motor UPDRS scores were not improved by GDNF at any dose. Nausea, anorexia, and vomiting were common hours to several days after injections of GDNF. Weight loss occurred in the majority of subjects receiving 75 microg or larger doses of GDNF. Paresthesias, often described as electric shocks (Lhermitte sign), were common in GDNF-treated subjects, were not dose related, and resolved on discontinuation of GDNF. Asymptomatic hyponatremia occurred in over half of subjects receiving 75 microg or larger doses of GDNF; it was symptomatic in several subjects. The open-label extension study had similar AE and lack of therapeutic efficacy. CONCLUSIONS: GDNF administered by ICV injection is biologically active as evidenced by the spectrum of AE encountered in this study. GDNF did not improve parkinsonism, possibly because GDNF did not reach the target tissues--putamen and substantia nigra.

Control of movement distance in Parkinson's disease.

Studies of electromyographic (EMG) patterns during movements in Parkinson's disease (PD) have often yielded contradictory results, making it impossible to derive a set of rules to explain how muscles are activated to perform different movement tasks. We sought to clarify the changes in modulation of EMG parameters associated with control of movement distance during fast movements in patients with PD. Specifically, we studied surface EMG activity during rapid elbow flexion movements over a wide range of distances (5-72 degrees) in 14 patients with relatively mild symptoms of PD and 14 control subjects of similar age, sex, height, and weight. The PD group exhibited several changes in EMG modulation including impaired modulation of agonist burst duration; increased number of agonist bursts; reduced scaling of agonist EMG magnitude in the more severely impaired subjects; and increased temporal overlap of the antagonist and agonist signals in the most severely impaired subjects. These findings suggest that progressive motor dysfunction in PD is accompanied by increasing deficits in modulating muscle activation. These results help clarify previous disparate and sometimes contradictory results of EMG patterns in subjects with PD.

A randomized, double masked, controlled trial of botulinum toxin type A in essential hand tremor.

OBJECTIVE: To evaluate the safety and efficacy of botulinum toxin type A injection in essential tremor of the hand. BACKGROUND: Botulinum toxin type A is an effective treatment for dystonia, spasticity, and other movement disorders and has been found to be useful in open-label studies and one double-masked study of essential hand tremor. METHODS: One hundred thirty-three patients with essential tremor were randomized to low-dose (50 U) or high-dose (100 U) botulinum toxin type A (Botox) or vehicle placebo treatment. Injections were made into the wrist flexors and extensors. Patients were followed for 16 weeks. The effect of treatment was assessed by clinical rating scales, measures of motor tasks and functional disability, and global assessment of treatment. Hand strength was evaluated by clinical rating and by a dynamometer. RESULTS: Both doses of botulinum toxin type A significantly reduced postural tremor on the clinical rating scales after 4 to 16 weeks. However, kinetic tremor was significantly reduced only at the 6-week examination. Measures of motor tasks and functional disability were not consistently improved with botulinum toxin type A treatment. Grip strength was reduced for the low- and high-dose botulinum toxin type A groups as compared with the placebo group. Adverse reactions consisted mainly of dose-dependent hand weakness. CONCLUSION: Botulinum toxin type A injections for essential tremor of the hands resulted in significant improvement of postural, but not kinetic, hand tremors and resulted in limited functional efficacy. Hand weakness is a dose-dependent significant side effect of treatment at the doses used in this study.

A teaching videotape for the assessment of essential tremor.

UNLABELLED: Teaching videotapes, developed to aid in the evaluation of several movement disorders, have not been used in essential tremor research. As part of the Washington Heights-Inwood Genetic Study of Essential Tremor (WHIGET), we developed a reliable and valid tremor rating scale. Because this rating scale is currently being used by investigators at other centers, we developed a teaching videotape to aid in the consistent application of this scale. OBJECTIVE: To develop a teaching videotape for a revised version of the WHIGET Tremor Rating Scale and to assess the interrater agreement among raters who used this videotape to rate tremor. METHODS: The revised WHIGET Tremor Rating Scale was used to rate action tremor from 0 to 4 during six tests: arm extension, pouring, drinking, using a spoon, finger-to-nose, and drawing spirals. A 22-minute teaching videotape was developed that includes a 29-item educational section and a self-assessment section consisting of 20 examples of tremor ratings chosen by the two WHIGET study neurologists. Eight raters, including senior movement disorder specialists, movement disorder fellows, general neurologists, and a movement disorder nurse practitioner, independently viewed the videotape and rated tremor during the self-assessment section. Interobserver reliability was assessed with weighted kappa statistics (kappa(w)). RESULTS: Eight raters each rated 20 items (160 ratings total). Total kappa(w) was 0.97 (nearly perfect agreement). Interrater reliability was as follows: kappa(w) = 0.99 (movement disorder specialists), kappa(w) = 0.98 (movement disorder fellows), and kappa(w) = 0.97 (general neurologists); all kappa(w) were nearly perfect. CONCLUSIONS: This teaching videotape may be used to improve the uniform application of the revised WHIGET Tremor Rating Scale by raters with various levels of experience in movement disorders.