L. Tesio et al., Short form of the dizziness handicap inventory - Construction and validation through rasch analysis, AM J PHYS M, 78(3), 1999, pp. 233-241
Citations number
23
Categorie Soggetti
Ortopedics, Rehabilitation & Sport Medicine
Journal title
AMERICAN JOURNAL OF PHYSICAL MEDICINE & REHABILITATION
A new item response scale is presented, which measures the severity of self
-reported balance deficits. The scale, DHIsf, is a short form of the Dizzin
ess Handicap Inventory. The scale was constructed and validated by Rasch an
alysis. Rasch analysis was applied to rescore or remove any items misfittin
g, redundant, or off-target, until an optimal instrument was obtained. The
25-item, 3-level Dizziness Handicap Inventory was, thus, reduced to the 13-
item, 2-level DHIsf. The retained items explore the domains of eye/head mov
ements, full body activities, and mood alterations. Data were collected fro
m 55 outpatients (63 +/- 13 yr; 43 females) attending otoneurological rehab
ilitation referral at a general hospital because of complaints of dizziness
or imbalance. They were fully independent in ambulation and showed no evid
ence of major neurological or orthopedic diseases. Objective tests included
brain computed tomography, sovraaorctic Doppler sonography, craniocorpogra
phy, static posturography, and nystagmography. The findings were categorize
d as pathologic, borderline, or normal. At least one examination was border
line or abnormal in 42 patients. The DHIsf was well targeted on this sample
, with a mean score of 5.7/13 (standard deviation, 2.8; median, 5; range, 1
-13). The Rasch statistics showed that the 13 items evenly fitted a hierarc
hy of difficulty within a homogeneous construct. A moderate but significant
variance explanation of DHIsf measures was provided by a two-way analysis
of variance model, with craniocorpography and nystagmography as independent
categorical variables (r(2) = 0.15; P = 0.018). When the clinical tests we
re individually taken into account, their outcome (dichotomized as abnormal
v borderline or normal) could not be predicted by either of the DHIsf meas
ures or raw scores (logistic regression). The DHIsf compares favorably with
the original Dizziness Handicap Inventory, shows some consistency with the
instrumental findings, and provides original information on the severity o
f imbalance syndromes, as it is seen from the patient's perspective.