NINDS CDE Notice of Copyright
Please email the author for information about obtaining the instrument:
Supplemental: Huntington's Disease (HD)
|Short Description of Instrument||
Summary/Overview of Instrument: For the self-paced tapping task the participant uses either the dominant index finger or alternating thumbs to produce the target pace. An external input device (e.g., computer mouse) connected to a computer is used. Patients are asked to listen to a pacing tone, then begin tapping the specified buttons in time with the tone and to continue tapping at that same rate after the tone stops. The majority of the evidence for using this task in HD populations was collected with paces of 1.8 or 3.0 Hz.
Construct measured: Cognitive and motor timing.
Generic vs. disease specific: Generic.
Intended use of instrument/ purpose of tool (cross-sectional, longitudinal, diagnostic, etc): Assessment of cognitive function in HD cross-sectional and longitudinal studies. Suitable for measuring cross-sectional and longitudinal changes in paced tapping timing abilities.
Means of administration (paper and pencil, computerized): Computerized.
Location of administration (clinic, home, telephone, etc): Clinic.
Intended respondent (patient, caregiver, etc.): Patient.
# of items: N/A.
# of subscales and names of sub-scales: N/A.
Strengths: The task is quick, easy to administer, and among the most sensitive cognitive tasks for use in pre-manifest and early HD.
Weaknesses: Aging may play a significant role in a person's performance of the self- paced timing task and must be matched across groups or considered in interpretation of findings.
Administration Time: One condition (e.g., alternate thumbs at 1.8 Hz) takes about 3 minutes.
Translations available (e.g. Spanish, French, Other languages): Dutch, French and English.
The precision of all taps taken together is directly estimated. Timing precision is calculated as the reciprocal of the standard deviation (SD) of the intertap interval. The reciprocal of SD is preferred because it more closely satisfies statistical modeling assumptions of linear relationships to covariates of interest, approximate normality, and maintains constant variance of the differences between observed and predicted values.
Standardization of scores to a reference population (z scores, T scores, etc): N/A.
If scores have been standardized to a reference population, indicate frame of reference for scoring (general population, HD subjects, other disease groups, etc). N/A.
Test-retest or intra-interview (within rater) reliability (as applicable): N/A
Inter-interview (between-rater) reliability (as applicable): N/A
Internal consistency: N/A
Statistical methods used to assess reliability: Test-retest correlations
Reliability data from the CAB study will be available by end of 2012 for 100 control, 100 pre-manifest, and 50 early HD subjects.
Content validity: N/A.
Construct validity: N/A.
Sensitivity to Change/ Ability to Detect Change (over time or in response to an intervention): In TRACK-HD (unpublished), for both 1.8 and 3.0 Hz conditions, cross- sectional differences from controls were detected in pre-manifest HD and early HD. PREDICT-HD also found cross-sectional differences from controls in the 1.8 Hz condition in pre-manifest HD (Stout et al., 2011).
In TRACK-HD (Stout et al., under review), early HD longitudinal annualized change over 24 months for the 3.0 Hz condition differed from change in controls. However, this was not the case for pre-manifest HD compared to controls.
PREDICT-HD (Rowe et al., 2010) detected annualized longitudinal change over time (7 years) in the 1.8 Hz condition in pre-manifest HD. However, in TRACK-HD, the 1.8 Hz condition did not show different rates of change for either pre-manifest HD or early HD as compared to controls (Stout et al., in submission).
Known Relationships to Other Variables (e.g. gender, education, age, etc): In PREDICT- HD, performance was related to education, age, and gender. In TRACK-HD, performance was related to education but not age or gender; change in performance was related to age but not to gender or education.
Diagnostic Sensitivity and Specificity, if applicable (in general population, HD population- pre-manifest/ manifest, other disease groups).
Rowe KC, et al. Self-paced timing detects and tracks change in prodromal Huntington disease. Neuropsychology 2010; 24(4):435-442.
Stout, J. C., Paulsen, J. S., Queller, S., Solomon, A. C., Whitlock, K. B., Campbell, J. C. et al. (2011). Neurocognitive signs in prodromal Huntington disease. Neuropsychology, 25, 1-14.
Tabrizi SJ, et al. Biological and clinical changes in pre-manifest and early stage Huntington's disease in the TRACK-HD study: the 12-month longitudinal analysis. Lancet Neurology 2011; 10: 31-42.
Stout JC et al. Evaluation of longitudinal 12- and 24-month cognitive outcomes in pre- manifest and early Huntington's disease. In submission 2011.