Federal government websites often end in .gov or .mil. LIS contributed to plan the article and relevant statistical analysis, helped to interpret results, to draft and write the article. after a programme of vestibular rehabilitation therapy), then a change of 18 points in the overall score is needed for the clinician to consider this a true change. The translation followed international guidelines through a process of reviews and modification [28,29]. According to Terwee et al. Zimbelman JL, Stoecker J, Haberkamp TJ. Finch E, Brooks D, Stratford PW, Mayo NE. Five ordinal response categories range from 'never' (score 0) to 'very often (most days)' (score 4), and give a total score ranging from 0 to 60, the VSS-sf-V ranges 0-32, and VSS-sf-A ranges 0-28, higher scores indicating more severe symptoms [32]. The number of 'worsened' (n = 4) was too small to determine minimally important change for deteriorated, and they were therefore excluded from the analysis. Vereeck L, Truijen S, Wuyts F, Heyning PH Van de. Best Practices in Exploratory Factor Analysis: Four Recommmendations for Getting the Most From Your Analysis. to detect self-perceived important change in the construct being measured using an anchor based approach. Practical Assessment, Research and Evaluation. The criterion for improvement was a reduction of 2 or more categories on the Disability Scale. No floor or ceiling effects were demonstrated. The DHI-N demonstrated excellent ability to discriminate between participants with and without 'disability', AUC being 0.89, and the best cut-off point for discrimination was 29 points. Comparison of subjective and objective measurements of balance disorders following traumatic brain injury. The Disability Scale assesses self-perceived disability, has favourable levels of ordinal categories, a change in categories imply important clinical change, and high concurrent correlation with the DHI-N indicates similar functional constructs.

Validity and reliability of patients' self-report of functioning. Measuring Outcome from VestibularRehabilitation, Part II: Refinement and validation of a new self-report measure.International Journal of Audiology, 48 pages 24-37. The DHI-N demonstrated excellent ability to discriminate between self-perceived 'improved' versus 'unchanged' participants, AUC being 0.83. Five items were below minimum loading (items 4, 10, 12, 17, and 20). The scree plot (Figure (Figure1)1) indicated two obvious factors to be retained for rotation. All authors read and approved the final version. The translated version was pilot tested on a few Norwegian speaking patients with dizziness (n = 4), and no particular problems were met regarding answering the questions. Factor II comprised items included in the original physical subscale, in addition to one from the emotional and four from the functional subscales (Table (Table2).2).

Archives of Otolaryngology Head Neck Surgery, 116 pages 424 - 427. Considerations of the area under the ROC curve (AUC) followed guidelines presented by Hosmer and Lemeshow [52]: 0.5 no discrimination; 0.7 ROC < 0.8 acceptable discrimination; 0.8 ROC < 0.9 excellent discrimination; and ROC 0.9 outstanding discrimination. Databehandling og statistisk analyse med SPSS. Understanding the relevance of measured change through studies of responsiveness. Test-retest reliability of the Dutch version of the Dizziness Handicap Inventory. The smallest detectable difference for an individual (SDDind) was accordingly 19.67 points on the DHI-N, while the smallest detectable difference for a group (SDDgroup) was 3.78 points. While the DHI-N items appear to capture the limiting effect of dizziness on performance of activities, the VSS-sf-N items appear to capture severity of symptoms, reflecting impairments of body functions [60]. The association was found to be particularly high between DHI-N total score and the COOP/WONCA chart C. daily activities. The scores of the DHI-N ranged from 4 to 86 DHI points in sample 1, and 11% of the participants had < 20 DHI points and 1% had 80 DHI points. The present study is the first to address and demonstrate this ability in the DHI scale, i.e. The hypothesis of high association between the sum scores of the DHI-N and COOP/WONCA was confirmed, but the association was higher than expected, taking into consideration that the COOP/WONCA is a generic measure. HHS Vulnerability Disclosure, Help Satisfactory reliability of preferred gait speed (meters pr. It is important to note that the scores someone provides on the DHI will not always relate closely with the evidence of peripheral vestibular dysfunction that is indicated by the vestibular test battery.

Tests, scores and examination of validity of the DHI-N (n = 92, sample 1). Sample 1 had a broader recruitment, and also included participants with non vestibular and unknown origin of dizziness, and was thus neither directly comparable to sample 2, nor to the sample used in development of the scale. The anchor based MIC was identified as 11 DHI-N points. Demographics and test data were examined by descriptive statistics. It is scored on a 6-point ordinal scale: 0 = 'no disability; negligible symptoms', 1 = 'no disability; bothersome symptoms', 2 = 'mild disability; performs usual work duties, but symptoms interfere with outside activities', 3 = 'moderate disability; symptoms disrupt performance of both usual work duties and outside activities', 4 = 'recent severe disability; on medical leave or had to change job because of symptoms', and 5 = 'long-term severe disability; unable to work for over 1 year or established permanent disability with compensation payment' [43]. Scree Plot of eigenvalues of DHI-N items by exploratory factor analysis (EFA) (n = 92, sample 1). Liang MH. Item loadings were evaluated in line with proposals from Costello and Osborne [50]: Item loadings < 0.40 suggest that an item is not sufficiently related to the other items in the factor, or indicates an additional factor to be explored; the minimum loading of an item is suggested = 0.32; and loadings 0.32 on two or more factors, indicate cross-loadings. Construct validity of the DHI-N was supported, as the predefined hypotheses of concurrent correlations with other measures, were confirmed. The https:// ensures that you are connecting to the Satisfactory internal consistency of the total scale was found. Johansson M, Akerlund D, Larsen HC, Andersson G. Randomized controlled trial of vestibular rehabilitation combined with cognitive-behavioral therapy for dizziness in older people. Factor II comprised items from the original physical in addition to functional subscales.

It is a very positive step to use these questionnaires alongside the VNG tests to support your diagnosis, guide decision-making and chart progress of patients. Mean scores of the first test were somewhat higher than retest scores, but the difference between ICC(1,1) and ICC(3,1) analysis was minimal, showing little systematic change from the first to the second test.

The handicapping effect of dizziness (DHI-N) and functional health status (COOP/WONCA sum score) may represent related functional problems according to ICF [60]. Fielder H, Denholm SW, Lyons RA, Fielder CP. The correlations between change in DHI-N scores and those of the other self-report measures were high, correlation coefficients (r) ranging 0.50-0.57 (Table (Table4).4). second) has been shown in different patient populations [46], as well as in patients with peripheral vestibular disorders [44]. Factor I comprised almost all items included in the original emotional subscale, in addition to four items in the functional subscale (Table (Table2).2). The use of change in gait speed to validate change in the DHI-N scale may therefore be questioned. The Disability scale was found suitable as an external criterion of change in the construct being measured, r being 0.51 (Table (Table4).4). Satisfactory measurement properties have been reported in different patient populations [35,37,38], also in the Norwegian version [39-42]. The results from participants with multiple origins of dizziness, are thus also in line with previous findings from patients with vestibular disorders [13,61]. [46], change scores of measures at different functional levels (ICF) could be expected to correlate between r = 0.2 - 0.5. Duracinsky M, Mosnier I, Bouccara D, Sterkers O, Chassany O. The highest correlation was found between the DHI-N and VSS-sf-N total (r = 0.69). Later studies of the underlying factor structure of the DHI failed to support the empirically developed sub-domains [9-11], which was also adressed in a recent review article [12]. The answers to the 25 questions are marked to give a total score (from 0 to 100 points), which provides an indication of the handicapping effect of dizziness. Scores are derived from each individual chart (range 1-5), or as a sum score (range 5-25) of 5 charts (excluding chart E: changes in health) [35,36]. Distributions of scores were examined by Q-Q plots and by comparing mean and median of the scales and subscales. The aim of the present study was to examine reliability and validity of a translated Norwegian version (DHI-N), also examining responsiveness to important change in the construct being measured. Following informed consent, consecutive participants in sample 1 received self-administered questionnaires, to be returned by mail prior to the appointment for interview and baseline testing. The sample size for the factor analysis should preferably be 4-10 subjects pr item [27,50]. A cross-sectional design was used to examine the factor structure (exploratory factor analysis), internal consistency (Cronbach's ), concurrent validity (Pearson's product moment correlation r), and discriminate ability (ROC curve analysis). The DHI has been used in previous studies to explore change in general and change in scores due to effect of treatment [7,12,16], thus indicating sensitivity of the DHI, according to the definitions above. The participants in sample 2 were part of a larger study approved by the Regional Committee for Medical Research Ethics West, Norway.

Differences between groups were checked by t-tests and ANOVA. COOP/WONCA is a generic assessment tool measuring perceived functional health status referring to the last two weeks. Knowledge of absolute reliability of an instrument allows identification of change beyond measurement error. In agreement with several authors [27,46,48,62], the ability to discriminate between participant groups that are known to have a trait or condition of interest, and those who do not (i.e. However, patients seen at tertiary referral centres are referred from General Practitioners in primary health care and from other medical specialists. This is the first study that has addressed and demonstrated anchor based responsiveness of the DHI to self-perceived clinically important change, also providing values of SDD, and MIC to help interpret change scores. Before The ability of the DHI to discriminate between change scores in groups of participants with dizziness who were expected to change differently according to the treatment received, has been demonstrated in the original version [18,21,23,24], and also in a translated version [17,25]. A change of 7% in the overall score is needed for the clinician to consider this a true change. The study was performed in accordance with the Helsinki Declaration.

Yardley L, Burgneay J, Andersson G, Owen N, Nazareth I, Luxon LM. Longitudinal designs were used to examine test-retest reliability (intraclass correlation coefficient (ICC) statistics, smallest detectable difference (SDD)), and responsiveness (Pearson's product moment correlation, ROC curve analysis; area under the ROC curve (AUC), and minimally important change (MIC)). ICC values 0.70 are considered satisfactory [27,53]. Vocational disability caused by dizziness and vertigo is an infrequent cause of certified sickness absence, but people with long term sickness-absentees with dizziness/vertigo, have a considerable risk of obtaining disability pension in the future [45]. The factor structure was identified by using the oblique rotation method (Oblimin) with delta = 0 allowing for moderate correlation [49]. We applied exploratory factor analysis (EFA), which is recommended when the factor structure of a measure has not been established [49,50]. Change scores of the DHI-N were explored in ROC curve analyses using this dichotomized scale of 'improved' and 'unchanged' participants as dependent variable. A somewhat higher correlation seen in the original study may be due to short retest interval (same day). Outcome in Vestibular rehabilitation. Within-subject standard deviation (Sw) denotes measurement error, and is expressed in the unit of the measurement tool. In further analysis, only measurement properties for the total scale were thus examined. The scale did not show significant relationship with changes in gait speed.

aItem loadings are presented according to the abbreviated item description of sub domains of the original version of the DHI questionnaire (physical, emotional and functional subscales). Balance Function Test Correlates of the Dizziness Handicap Inventory. Cattaneo D, Jonsdottir J, Zocchi M, Regola A. Exclusion criteria were evidence of central vestibular disorder or progressive vestibular pathology, including Mnire's disease, genetic hearing loss and/or neurological/musculoskeletal/visual/psychiatric disorders.

References and caveatsJacobson, G.P. The original and the back-translated English versions were compared by the three translators, and if discrepancies were found, the Norwegian version was adjusted to optimize conceptual overlap [30]. Kaufman KR, Brey RH, Chou L-S, Rabatin A, Brown AW, Basford JR. 8600 Rockville Pike However, taking into consideration that the DHI-N is a broad self-report measure and gait tests a performance measure that only yields one test result, a moderate correlation is more realistic [48]. Factor structure and item loadings of the DHI-N by exploratory factor analysis (n = 92, sample 1). Whitney SL, Wrisley DM, Brown KE, Furman JM. Skoien AK, Wilhelmsen K, Gjesdal S. Occupational disability caused by dizziness and vertigo: a register-based prospective study. These studies did, however, not address responsiveness as a quality of the DHI questionnaire to detect important and real change in the constructs being measured. Kinnersley P, Peters T, Stott N. Measuring functional health status in primary care using the COOP-WONCA charts: acceptability, range of scores, construct validity, reliability and sensitivity to change. Concurrent correlations between the DHI-N and other related measures were moderate to high, highest with Vertigo Symptom Scale-short form-Norwegian version (r = 0.69), and lowest with preferred gait (r = - 0.36). Intra-individual differences between the DHI-N scores at test and retest plotted against the mean DHI-N change scores (n = 27, sample 2). The scoring provides a percentage scale, where 0% is no deficit compared with the patients own normal state, and 100% is the maximum deficit. Factor III comprised two items from the original emotional and two from the functional subscales. Other relevant external criteria of important change might also be explored in future studies, still realizing the lack of 'a golden standard'. All rights reserved. Previously, the DHI has also shown ability to discriminate between groups of dizzy patients according to frequency of dizziness episodes [1], and levels of functional impairment [13]. No absolute value is recommended, but should preferably be small for instruments to be useful as an outcome measure. The .gov means its official. To acknowledge the ordinal nature of the DHI, correlations were also explored by Spearman's rho, but as similar values of correlation coefficients were found, they are not reported. This is in line with the associations that were found between the scales in cross-sectional analysis. Received 2009 Mar 12; Accepted 2009 Dec 21. Written informed consent was obtained from all participants. and Newman, C.W. Physical Rehabilitation Outcome Measures. to chart progress e.g.

However, the optimal cut-off point of 11 DHI-N points, the anchor based MIC, was within the limits of measurement error at the level of an individual (SDDind 20 DHI-N points), but exceeded the level estimated for groups (SDDgroup 4 DHI-N points). Inclusion criteria were dizziness, age range 20-65 years, ability to read and understand Norwegian language, and living in the Oslo-Akershus region. The DHI scores range from 0 to 100. Degree of linear relationships between variables were quantified by Pearson's correlation coefficient (r), and evaluated in line with guidelines proposed by Cohen [51]: r = 0.10 - 0.29 = small (low correlation); r = 0.30 - 0.49 = medium (moderate correlation); r = 0.50 - 1.0 = large (high correlation) [51]. Statistics notes: Measurement error. Results from the EFA revealed that the items of the DHI-N loaded differently, than the suggested three sub-domains of the original version. Previous findings of correlations between the DHI and subscales of the generic SF-36, ranged from 0.11 to 0.71 [15,16]: Fielder et al. SDDind estimated in sample 2 were in line with the initial findings in the DHI (SDD 18) [1]. (1990) The development of the dizzinesshandicap inventory. Changes of 6% and 9% are needed for the clinician to consider a true change in the Symptoms and Quality of Life halves, respectively. The smallest detectable difference of a group of people (SDDgroup) can be calculated by dividing the SDDind by vn [27,55].

Instrument translation process: a methods review. Items included in the DHI were originally derived from case histories of patients with dizziness, and the measure was further examined in several studies involving patients seen for vestibulometric testing [1]. Measuring Functional Status in a Population Survey.

Absolute agreement (Sw) was 7.1. In the 3-factor solution, factor I comprised items originally included in the emotional and functional subscales (Table (Table2).2).

Perez N, Garmendia I, Garcia-Granero M, Martin E, Garcia-Tapia R. Factor analysis and Correlation Between Dizziness Handicap Inventory and Dizziness Characteristics and Impact on Quality of Life Scales. Yardley L, Donovan-Hall M, Smith H, Wash BM, Mullee M, Bronstein AM. Measurement properties of the DHI-N seemed, accordingly, to be highly satisfactory. The items included in the DHI, were considered relevant and adequate for dizzy patients in the Norwegian culture, which was a prerequisite for translating the measure [29]. The second half assess the impact of dizziness upon quality of life. The site is secure. Translations from American to Norwegian were made separately by two physiotherapists familiar with dizzy patients and knowledgeable in American and English. Test-retest reliability of the DHI-N was satisfactory (ICC 1,1 = 0.90). The hypothesis of acceptable discrimination was confirmed, and construct validity was supported. The highest association between change scores of the DHI-N and the VSS-sf-N indicated similar constructs; a reduction in perceived handicapping effect of dizziness was associated with a reduction in perceived frequency of symptoms of dizziness. Forms with missing values exceeding 7 items (30%) of the DHI-N total or exceeding 30% of the items in a DHI-N sub-domain, were excluded from analysis. The reason for referral is often associated with uncertain aetiologies, thus probably presenting a multitude of origins. The cut-off point for best discrimination was 29 points, correctly classifying 85% of participants with 'disability' and 79% with 'no disability'. Evaluating Measurement Responsiveness. Concurrent correlation between the DHI-N and other measures of related constructs were moderate to high, highest for the VSS-sf-N and lowest for preferred gait speed. Jarlster S, Mattson E. Test of reliability of Dizziness Handicap Inventory and the Activities-specific Balance Confidence Scale for use in Sweden. The Dartmouth Functional Health Assessment Charts/Wonca used in a Epidemiological Study. The ability to detect real change in the concept being measured, or the ability to distinguish between participants who have and have not changed an important amount [26,27], have not been reported. Maneesriwongul W, Dixon JK. Careers. Hall CD, Herdman SJ. The AUC was used as a measure of responsiveness, and AUC > 0.70 is considered adequate [27]. ), and 'overall health' (F. How would you rate your health in general?) Internal consistency, validity and responsiveness of the DHI-N were examined in sample 1. A manual. The form was returned by 28 (88%) patients. Murray K, Carroll S, Hill K. Relationship between change in balance and self-reported handicap after vestibular rehabilitation therapy. An official website of the United States government. Terwee CB, Dekker FW, Wiersinga WM, Prummel MF, Bossuyt PMM. Responsiveness of the DHI-N was also examined by using an anchor-based method [27,57]. The DHI is intended to measure the handicapping effects of dizziness on physical, emotional and functional sub-domains [1]. The charts include 'physical fitness' (A.

The factor analysis revealed a different factor structure than suggested in the original version, resulting in dismissal of subscale scores. Minimally important change determined by a visual method integrating an anchor-based and a distribution-based approach. The DHI-N showed excellent ability to discriminate between participants who reported 'disability' (n = 68) and 'no disability' (n = 24), according to the area under the ROC curve: AUC being 0.89 (95% CI 0.81-0.97), as shown in Figure Figure2.2. Responsiveness of the DHI-N was supported, as the hypotheses of correlations between change scores of the DHI-N versus the VSS-sf-N total, as well as the COOP/WONCA sum, were confirmed. Back-translation was performed by a bilingual person with Norwegian and English at a professional academic level, and with English as a native language. However, the DHI-N is a broader self-report measure, including a multitude of items, while gait tests are performance based and provide separate measures of gait. Krebs DE, Gill-Body KM, Riley PO, Parker SW. Double-blind, placebo-controlled trial of rehabilitation for bilateral vestibular hypofunction: preliminary report. The ability of the DHI to measure meaningful or clinically important change, has scarcely been examined [12], and variable results regarding the ability of the DHI to discriminate between treatment and control groups, have been found in randomized controlled trials [17-25]. However, to be in line with a recently published version [31], the sequence of response categories were changed, as shown in Additional file 1. Correlation between change scores of the DHI-N and those of other self report measures, were high. Translation of the Dizziness Handicap Inventory into chinese, validation of it, and evaluation of the quality of lifw of patients with chronic dizziness. Previous results from principal components analysis (PCA) of the DHI in the original language [9], as well as of other translated versions [10,11], have demonstrated various underlying factor structures. Accessibility The same physiotherapist interviewed and tested all participants on both occasions. Measuring functional health status with the COOP/WONCA Charts. Mruzek M, Nichols DS, Burnett CN, Welling DB. Bethesda, MD 20894, Web Policies In this cross-sectional and longitudinal study of patients with dizziness, measurement properties of a translated and adapted Norwegian version of the Dizziness Handicap Inventory (DHI-N), were examined. Hansson EE, Mansson NO, Ringsberg KAM, Hakansson A. Dizziness among patients with whiplash-associated disorder: a randomized controlled trial. Bruusgaard D, Nessoy I, Rutle I, Furuseth K, Natvig B. Repairing Tom Swift's Electric Factor Analysis Machine. The new PMC design is here! Major loadings for every item 0.32 are bold face. Statistical power analysis for behavioural sciences. After translating the DHI into Norwegian, the aim of the present study was to examine reliability and validity of the translated version, which was to be used as a descriptive and evaluative measure. However, as acceptable sampling adequacy was demonstrated, we considered the sample size (n = 92) acceptable for exploring the factor structure in the present study. The second tool that you mentioned is the VRBQ. The participants in sample 1 were part of a larger study approved by the Regional Committee for Medical Research Ethics, Health Region South, Norway. Yardley L, Kirby S. Evaluation of booklet-based self management of symptoms in Meniere Disease: a randomized controlled trial. It was favourable that the participants in the present study reported a wide range of scores on the DHI-N questionnaire, without showing floor or ceiling effects. The hypothesized strength of correlations between change scores, were as previously defined for construct validity. Features and/or functions may not be available for all countries or all areas and product specifications are subject to change without prior notification. Highest association was found between change in the DHI-N and the condition specific VSS-sf-N (r = 0.57). Wilhelmsen K, Strand LI, Nordahl SHG, Eide GE, Ljunggren AE. Internal consistency and factor analysis of the Dutch version of the Dizziness Handicap Inventory. Therefore, dizziness, rather than the origin of dizziness, should probably be the indication for using the questionnaire. Analyses of the gait tests were based on the mean scores of two trials. Internal consistency of the DHI-N total scale by Cronbach's alpha was above the recommended limits [48], and in line with previous results [1]. Principles and applications. Vereeck L, Truijen S, Wuyts FL, Heyning PH Van de. Health Measurement Scales a practical guide to their development and use. Although the DHI-N subscale scores were abandoned in the present study, the results indicate that the DHI-N includes similar physical and emotional constructs, as the VSS-sf-N. Factor analysis revealed a different factor structure than the original DHI, resulting in dismissal of subscale scores in the DHI-N. To examine construct validity, scores of the DHI-N were correlated with those of condition specific and generic measures. High correlations were shown between the DHI-N and the VSS-sf-N total, the VSS-sf-N sub-scales, the COOP/WONCA and the Disability scale (r ranging 0.50 - 0.69) (Table (Table3).3). Several authorities [55,64,66], define sensitivity to change as the ability of an instrument to detect change in general, while responsiveness is defined as the ability of an instrument to detect a clinically important change, and a real change in the concept being measured. Want to know more about our products or arrange a demonstration? Three items loaded below minimum (items 4, 10, and 12), and four items cross-loaded (item 3, 7, 15 and 22), indicating a possible additional factor (Table (Table2).2). Measurement of health status in patients with vertigo. Missing values in the included forms, were replaced by the mode value of the respective DHI-N sub-domain [47]. We further hypothesized that the DHI-N and gait tests assessed similar physical constructs, because gait is influenced by dizziness, and gait is performed in many daily activities as well as in social situations. Sample 1 also included participants with unknown origin of dizziness and non-vestibular dizziness, the latter mainly represented by anxiety, neck problems and sequelae of head and/or neck trauma. Exclusion criteria were dizziness because of cardio-vascular disease, neurological or other severe system diseases, and not being able to answer the questionnaires or go through physical tests. The results support construct validity of the DHI-N. 98 participants were included. Correlations between change scores of DHI-N and other self-report measures of functional health and symptoms were high (r = 0.50 - 0.57). Enloe LJ, Shields RK. Cohen HS, Kimball KT. Effects of vestibular rehabilitation and social reinforcement on recovery following ablative vestibular surgery.

If the DHI is being used as an outcome measure (i.e.

Potential participants with complaints of dizziness from the Oslo-Akershus region were recruited from General Practice, ENT-specialists and the National Insurance Administration (NIA 2003-2004). Test-retest reliability was examined by intraclass correlation coefficients (ICC) [53]. As there tended to be a systematic change in scores between repeated measurements (Figure (Figure3),3), this should probably also be taken into consideration when judging change scores. The area under the ROC curve indicated excellent discriminate ability according to recommended limits [27].

Maximum likelihood parameter extraction technique and the scree plot were used to determine the numbers of factors to be retained for analysis [49]. A sample size 50 is, however, proposed in test-retest reliability studies [27], while in our study of test-retest reliability, only 27 participants were included. At the time of the second test, sample 1 had 72 participants. A Guide to Enhanced Clinical Decision Making. Permission to translate the DHI into Norwegian was granted by Gary P. Jacobson, one of the test developers [1]. Preacher KJ, MacCallum RC. The mean age and gender of the participants in sample 2, were comparable to the participants included when the original DHI scale was developed and tested [1].

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