SPINE Volume 40, Number 14, pp 1115-1121 ©2015, Wolters Kluwer Health, Inc. All rights reserved.

HEALTH SERVICES RESEARCH

The Neck Disability Index–Russian Language Version (NDI-RU) A Study of Validity and Reliability Maxim A. Bakhtadze, MD, PhD,* Howard Vernon, DC, PhD,† Olga B. Zakharova, MD,‡ Kirill O. Kuzminov, MD, PhD,* and Dmitry A. Bolotov, MD, PhD*

Study Design. Cross-cultural adaptation and psychometric testing. Objective. To perform a validated Russian translation and then to evaluate the validity and reliability of the Russian language version of the Neck Disability Index (NDI-RU). Summary of Background Data. Neck pain is highly prevalent and can greatly affect daily activity. The Neck Disability Index (NDI) is the most frequently used scale for self-rating of disability due to neck pain. Its translated versions are applied in many countries. However, the Russian language version of the NDI has not been developed yet. Methods. Cross-cultural adaptation of the NDI-RU was performed according to established guidelines. Then, the NDI-RU was evaluated for content validity, concurrent criterion validity, internal consistency, test-retest reliability, factor structure, and minimum detectable change. Results. Two hundred thirty-two patients took part in the study in total: 109 in validity (39.5 ± 10 yr), 123 in reliability (38.4 ± 11 yr; 80 in the test-retest phase). A culturally valid translation was achieved. NDI-RU total scores were distributed normally. Floor/ ceiling effects were absent. Good values of Cronbach α were obtained for each item (from 0.80 to 0.84) and for the total NDI-RU (0.83). A 2-factor solution was found for the NDI-RU. The average

From the *Department of Neurology, Neurosurgery and Medical Genetics, Russian National Research Medical University (named after N. I. Pirogov), and Department of Manual Therapy, Center for Manual Therapy, Moscow, Russia; †Canadian Memorial Chiropractic College, Toronto, Ontario, Canada; and ‡Department of Physiotherapy, Moscow City Hospital, Moscow, Russia. Acknowledgment date: February 4, 2014. First revision date: May 1, 2014. Second revision date: August 13, 2014. Third revision date: October 23, 2014. Fourth revision date: January 9, 2015. Fifth revision date: February 9, 2015. Acceptance date: March 9, 2015. The manuscript submitted does not contain information about medical device(s)/drug(s). No funds were received in support of this work. No relevant financial activities outside the submitted work. Address correspondence and reprint requests to Maxim A. Bakhtadze, MD, PhD, Department of Neurology, Neurosurgery, and Medical Genetics, Russian National Research Medical University (named after N.I. Pirogov) Clinical City Hospital No 1. Leninsky prospect, building 8, corpus 8, 117149 Moscow, Russia; E-mail: [email protected] DOI: 10.1097/BRS.0000000000000880 Spine

interitem correlation coefficient was 0.53. Intraclass correlation coefficients for test-retest reliability coefficients ranged from 0.65 to 0.92 for different items and 0.91 for the total NDI-RU. Moderate correlation (Spearman rs = 0.62; P < 0.05) was found between the NDI-RU total score and graphic rating scalepain score. Completion of the NDI-RU takes 3.6 ± 1 minutes. Conclusion. The development of a Russian language version of the Neck Disability Index resulted in a valid, reliable instrument that can be used both in clinical practice and scientific investigations. Key words: content validity, cross-cultural adaptation, health measurement scale, internal consistency, neck pain, Neck Disability Index. Level of Evidence: 1 Spine 2015;40:1115–1121

M

usculoskeletal disorders are highly prevalent in modern societies. Musculoskeletal-related disabilityadjusted life-years account for 6.8% of total disability-adjusted life-years.1 Of this, neck pain accounts for nearly a fifth. Years lived with disability increased for neck pain from 23,866,000 to 33,640, 000 years in 21 global regions from 1990 to 2010.1 To assess the impact of neck pain on daily activities, a reliable, responsive, self-report health measurement scale—the Neck Disability Index (NDI)—was recommended by the Bone and Joint Decade 2000–2010 Task Force on Neck Pain and Its Associated Disorders.2 Developed in 1989 as the first instrument, designed for measurement of self-rated disability in patients with neck pain, it was first published in 1991.3 By the year 2008, it was translated into 22 languages4 and this process is continuing today; new articles on cross-cultural adaptation were published during the last 3 years.5–16 However, the Russian language version of the NDI has not been developed yet. The goals of the present study were to develop a validated Russian translation and then to evaluate the cross-cultural validity and psychometric properties of the Russian language version of the NDI (NDI-RU). This will enable Russian clinicians and researchers to use the NDI in practice and to contribute to the worldwide literature on neck pain–related disability. www.spinejournal.com

1115

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1115

19/06/15 10:19 AM

HEALTH SERVICES RESEARCH MATERIALS AND METHODS Study Sample This study was conducted at the Center for Manual Therapy, established at the Russian National Research Medical University. Patients attending at the Center for Manual Therapy because of acute (≤12 wk) or chronic (≥12 wk) neck pain were recruited (Center for Manual Therapy is a governmental outpatient clinic, where manual therapy, being effective in treatment of mechanical neck pain,17,18 is available to all types of patients). The study was conducted using consecutive patients from September 2012 to April 2013. Patients experiencing both acute and chronic neck pain took part in the investigation. The sample represented predominantly the urban population of Moscow and Moscow region, who speak, read, and write in Russian fluently. To provide matching of the sample to target population, we included patients with grades I–III neck pain.18 Patients with grade IV neck pain (symptoms and signs of major structural pathology) and with psychiatric diseases were excluded. Besides, we excluded those who had already taken medications before the first visit and, also, subjects with acute pain requiring immediate treatment with medication.

Scales The NDI consists of 10 items: neck pain intensity, self-care, lifting, reading, headache, concentration, work, driving, sleeping, and recreation. For each item, there are 6 detractor statements, ordered for gradually increasing of severity from 0 (no problem) to 5 (worst problem). The total NDI score ranges from 0 to 50. Calculation of total score is made by scoring from 50. If 1 item was missed, the score out of 45 was adjusted to be out of 50.4 Two or more missing items invalidated the measurement. To investigate concurrent criterion validity of the NDIRU, we choose the 11-point numerical graphic rating scale (GRSpain), which is well-established instrument for measuring pain, including neck pain.19 In our study, numerical GRS was represented by a horizontal line, divided into 10 equal intervals by 11 vertical bars. Eleven numbers from 0 (corresponded to “no pain”) to 10 (“the worst pain possible”) were placed under each vertical bar. Patients were asked to circle the number corresponding to their pain intensity at the present moment. In some studies, such kind of scale is named just the graphic rating scale (GRS),20 or numerical rating scale.21 Cross-cultural Adaptation: Development and Testing of the Prefinal Version As recommended, cross-cultural adaptation was performed for several consistent stages.22–24 At first, 2 native Russians speakers (MD, PhD, experienced in working with healthrelated scales, and professional translator) performed 2 separate forward translations (T1 and T2) of the original NDI, which were sent to us by the second author (H.V.) with permission for adaptation. Furthermore, 1 common Russian language translation (T1-2) was synthesized by both translators 1116

NDI-RU: Adaptation, Validity, Reliability • Bakhtadze et al

and a recording observer. Then, 2 native English speakers (English language teachers skilled in Russian language) translated this T1-2 version separately back into English. After that, the expert committee (consisted of medical professionals, including the originator of the NDI, translators, and philologist) reviewed all forward and back-translated versions and developed the prefinal version of the NDI-RU. Finally, testing of this prefinal version stimulated us to bring the terminology for some items in agreement with that of the World Health Organization International Classification of Functioning, Disability, and Health.25 The final version was accepted after the expert committee agreed that there was nothing more to improve.

Procedures for the Psychometrics Phase At the first visit, patients completed the NDI-RU and 11-point GRSpain as a part of their routine investigation. To evaluate test-retest reliability, a second visit was appointed within 3 to 4 days. All patients signed written consent for participation in the study, approved by Ethical Committee of the Russian National Research Medical University.

Data Analyses Statistica 8.0 software (StatSoft., Inc., Tulsa, OK) and SPSS 14.0 software (IBM Corporation, White Plains, NY) were used for data analyses of the data from the reliability phase. These packages perform calculations accounting for missing data in the cells. Normality of total score distribution was analyzed using Kolmogorov-Smirnov and Lillieforse tests. Spearmen rank correlation coefficient rs was used for evaluation of correlation of each item to NDI-RU total score and correlation of the NDI-RU total score to 11-point GRSpain score. Cronbach α was used to assess internal consistency. Exploratory factor analysis was performed to identify the underlying relationships between measured variables. Cattel Scree Test was used to identify the number of extracted factors (eigenvalue >1). After varimax rotation had been applied, the items with the factor loading greater than 0.40 were included in the factor. To investigate test-retest reliability of the NDI-RU, we used intraclass correlation coefficient, 2-way random-effects model (ICC; (2,1)26). Floor and ceiling effects were analyzed descriptively and noted if any subject scored in the lowest or highest 10% of scores.26 The minimal detectable change (MDC) was calculated using the standard deviation (SD) of the change scores from the first to second NDI test-retest scores applied to the formula from Stratford 28 as MDC = 1.96 × SEM × , and SEM = , where SEM is standard error of measurement and 1.96 SEM is associated with a 95% confidential interval. Finally, in our case, MDC = 1.96 × SD. Our hypotheses were motivated by findings from previous cross-validation studies of the NDI and included the following: 1. The Cronbach α will be 0.7 or greater. 2. The strength of the relationship of the single item with the total scale will be fair to moderate (0.50 ≤ r ≤ 0.75).

www.spinejournal.com

July 2015

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1116

19/06/15 10:19 AM

HEALTH SERVICES RESEARCH 3. The strength of the relationship with GRSpain will be fair to moderate (0.50 ≤ r ≤ 0.75). 4. The ICC for the test-retest correlation will exceed 0.90.27 5. There will be no floor or ceiling effects in the NDI-RU.

RESULTS In total, 240 patients who applied to the clinic because of chronic or acute neck pain agreed to take part in the investigation. From them, patients with psychiatric diseases (n = 3), metastasis into the cervical spine (n = 2), rheumatoid arthritis (n = 1), acute infection disease (n = 1), and acute neck injury (n = 1) were excluded. From the remained 232 patients, 109 (mean age = 39.5 ± 10 yr) took part in the prefinal version testing, and 123 (mean age = 38.4 ± 11 yr) took part in the internal consistency and interitem correlation testing. Eighty patients from these 123 took part in test-retest reliability investigation. Self-reported duration of neck pain of these 123 patients averaged 5.54 years (from 1 mo to 27 yr).

Cross-cultural Adaptation: Development of the Prefinal Version We found semantic equivalent22–24 for all English words and phrases and named all the sections of the NDI-RU in accordance with the International Classification of Functioning, Disability, and Health25 (Table 1).

Psychometrics Phase One hundred twenty three patients completed the NDI-RU in this phase. The mean age of these subjects was 38.4 ± 11 years (from 20 to 67 yr); female—100 (81%); male—23 (19%). The sample size was considered to be adequate for the analyses as it was 10 times more than the number of items (NDI consists of 10) and greater than 100. Fifty-nine (48%) patients did not complete the section “Driving” because they did not have a driving license or did not use a car for transportation. This resulted in 59 of 1230 of missing data points

NDI-RU: Adaptation, Validity, Reliability • Bakhtadze et al

(4.8 %). This was deemed sufficiently low as to not affect the outcomes of the statistical analyses. We calculated the score of disability for each patient and for the whole sample. The average disability score resulted in 16.5 ± 7.6 (minimum—1; maximum—39 points). The sample came from a population with a normal distribution (Kolmogorov-Smirnov d = 0.08 with P > 0.20; Lillieforse P < 0.10). Descriptive characteristics of the sample are shown in Table 2.

Internal Consistency Table 3 shows the internal consistency of the NDI-RU. As seen from Table 3, acceptably high values26,28 of Cronbach α—from 0.80 to 0.83—were obtained for each item. Summary statistics for the NDI-RU are the following: (1) Cronbach α = 0.83; (2) Spearman interitem correlation coefficient R ranged from low to moderate (0.32 ≤ r ≤ 0.67); and (3) Average interitem correlation r = 0.53. The NDI-RU was quite understandable for the respondents, who completed it on average in 3.6 ± 1 minutes.

Test-Retest Reliability By the time of the first visit, most of the patients, who applied to our clinic for consultation and/or treatment because of neck pain, were examined properly: they have undergone their radiography or magnetic resonance imaging of the cervical spine and blood tests. Eighty-six of them were admitted for treatment in 3 to 4 days according to the clinic’s schedule. They completed the NDI-RU repeatedly at the second visit. These data were collected to investigate test-retest reliability of the NDI-RU. The data of the second completion of the NDI-RU by patients, who took nonsteroidal antiinflammatory drugs in the intervening period (n = 6), were excluded. Consequently, to investigate test-retest reliability of the NDI-RU, the data from 80 patients were calculated. Thirty-seven patients completed their examination, including

TABLE 1. Correspondence of the NDI-RU Items With ICF Categories Items of the NDI-RU

Categories and Domains in the ICF

Code in the ICF

Chapters and/or Domains in the ICF

Sleep functions

b 134

Mental functions

Pain in head and neck

b 28010

Sensory functions and pain

Concentration

d 160

Learning and applying

Reading

d 166

Knowledge (d1)

Lifting and carrying objects

d 430

Driving

Driving

d 475

Self-care

Self-care

d5

Self-care (d 5)

d6

Domestic life (d 6)

d8

Major life areas (d 8)

d 920

Community, social, and civil life (d 9)

Sleeping Neck pain intensity Headache Concentration Reading Lifting objects

Working ability Recreation and leisure

Recreation and leisure

Mobility (d4)

NDI-RU indicates Neck Disability Index–Russian language version; ICF, International Classification of Functioning, Disability, and Health.

Spine

www.spinejournal.com

1117

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1117

19/06/15 10:19 AM

HEALTH SERVICES RESEARCH

NDI-RU: Adaptation, Validity, Reliability • Bakhtadze et al

TABLE 2. Descriptive Characteristics of the

Sample, Means ± SD or N (%)

Characteristics

TABLE 3. Descriptive Data and Distribution of

Responses for Each Item for NDI-RU and Spearman Correlation Between Item Score and Total Score (N = 123)

Patients (%)*

Sex Female

100 (81)

Male

23 (19)

Age (yr)

38.4 ± 11

Educational level High

70 (57)

Mid

53 (43)

Work status Employed

91 (74)

Unemployed

32 (26)

Unemployed Pensioners House keepers Students

6 (5) 18 (14.5) 8 (6.5)

Stage of the disease Acute or exacerbation

38 (31)

Chronic

85 (69)

Signs and symptoms Neck pain Neck pain radiating to the head

38 (31) 51 (41.5)

Neuropathy of the great occipital nerve

12 (10)

Neck radiating to the arm

34 (28)

Discogenic radiculopathy

10 (8)

Numbness in 1 or both hands

64 (52)

Sensation of dizziness, unsteadiness

Sections of the NDI-RU

Item-Total Correlation

α if Deleted

Neck pain intensity

0.54

0.82

Self-care

0.54

0.82

Lifting objects

0.58

0.81

Reading

0.55

0.81

Headache

0.32

0.84

Concentration

0.36

0.83

Working ability

0.55

0.81

Driving

0.63

0.80

Sleeping

0.60

0.80

Recreation and leisure

0.67

0.80

NDI-RU indicates Neck Disability Index–Russian language version.

radiography, magnetic resonance imaging, and blood tests much later than 3 to 4 days. On that reason, these patients did not participate in test-retest phase. High values of the ICC for each item (95% confidential interval from 0.65 to 0.92) and for the whole NDI-RU (0.91) confirm excellent test-retest reliability (see Table 4).

Criterion Concurrent Validity Spearman rank correlation coefficient rs, between the NDIRU total score and GRSpain score, was 0.62, P value of less than 0.05.

123 (100)

TABLE 4. ICC Values for Each Item and the

123 (100)

Sections of the NDI-RU

ICC

95% CI

Neck pain intensity

0.67

0.53–0.78

Whole Scale (N = 80)

Syndromes Myofascial syndrome Headache Headaches total

108 (88)

Self-care

0.70

0.57–0.80

Moderate or severe headache

72 (59)

Lifting objects

0.65

0.50–0.76

Tension-type headache

52 (42)

Reading

0.72

0.60–0.81

Cervicogenic headache

33 (27)

Headache

0.92

0.88–0.95

Migraine

16 (13)

Concentration

0.73

0.61–0.82

Working ability

0.79

0.69–0.86

14 (11)

Driving

0.80

0.70–0.87

6 (5)

Sleeping

0.88

0.82–0.92

Recreation and leisure

0.79

0.69–0.86

Total score

0.91

0.86–0.94

Neck injury in anamnesis Motor vehicle accident Other types of neck injury The GRS score (IQR) The NDI-RU score

4.0 (2.0–5.0) 16.5 ± 7.6

GRS indicates graphical rating scale; IQR, interquartile range; NDI-RU, Neck Disability Index–Russian language version.

1118

NDI-RU indicates Neck Disability Index–Russian language version; ICC, intraclass correlation coefficient; CI, confidential interval.

www.spinejournal.com

July 2015

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1118

19/06/15 10:19 AM

HEALTH SERVICES RESEARCH

NDI-RU: Adaptation, Validity, Reliability • Bakhtadze et al

TABLE 5. Varimax-Rotated Factor Matrix of

the Neck Disability Index–Russian Language Version

Questionnaire

Factor 1 Sensory Factor 2 Sensory Function, Daily and Mental and Social Activity Functions

10. Recreation and leisure

0.76*

0.26

1. Neck pain intensity

0.74*

0.02

8. Driving

0.71*

0.30

2. Self-care

0.70*

0.24

3. Lifting objects

0.68*

0.21

7. Working ability

0.66*

0.30

6. Concentration

0.07

0.84*

9. Sleeping

0.22

0.76*

4. Reading

0.45

0.62*

5. Headache

0.18

0.43*

*The highest loading of each item.

Minimum Detectable Change This was calculated as 5.4 NDI points.

Floor and Ceiling Effect There were no floor or ceiling effects observed in the NDI-RU.

Factor Analyses Factor analyses (Table 5) with varimax rotation showed a 2-factor structure with eigenvalues greater than 1, explaining 55.2% of the total variance. The first factor had an eigenvalue of 4.4, explaining 43.9% of the variance. Cronbach α for the first factor is 0.82. The second factor had an eigenvalue of 1.1, explaining an additional 11.3% of the variance. Cronbach α for the second factor is 0.66. The first factor represents sensory function (neck pain), daily and social activities (driving, lifting objects, self-care, working ability, recreation, and leisure); the second factor represents mental and sensory functions (sleeping and headache), learning, and applying knowledge (concentration, reading).25

DISCUSSION This study describes cross-cultural adaptation and validation of the NDI-RU in patients with acute and chronic neck pain grades I–III.18 We developed an understandable and valid Russian language version of the NDI, following accepted guidelines and recommendations.18,22–24,29–34 NDI-RU took 3.6 ± 1 minutes for completion that is comparable with Italian (4.6 ± 2),7 Spanish (4 min),35 and Turkish (5.5 min)11 versions. The sample was presented by patients predominantly with moderate disability (16.5 ± 7.6). This corresponds to similar studies conducted in outpatient clinics.4,13,16,35,36 Higher Spine

values of disability (21.6 ± 8) have been reported for surgical patients.12 Females predominated in our sample (81%), as in most of the studies.3,6,7,13–15,35,37 The mean age (38.4 ± 11 yr) was found to be about the same with the original,3 Catalan,36 both Turkish and11,37 Spanish, and Dutch14 studies and differed from Greek,38 Iranian,39 Italian,7 Japanese,6 and both Polish12,13 and another Spanish35 studies, where the mean age varied from 45 to 62 years. Internal consistency of the NDI-RU was good (α = 0.83) and in an agreement with the original NDI,3 Dutch,14 Greek,38 Italian,7 Finish,10 Korean,40 and both Polish12,13 versions (0.80–0.85) and lower in comparison with Arabic,5 Catalan,36 Chinese,9 Iranian,39 both Japanese,6,41 both Spanish,16,35 Thai,42 and Turkish11 versions (0.87–0.93). Floor-ceiling effects were absent, as in most of the other studies. Test-retest within average of 3-day interval between completions was excellent (ICC = 0.93) and in agreement with the others. In our study, to investigate concurrent criterion validity of the NDI-RU, we gave to the patients 2 scales at the same time—NDI-RU and GRSpain—and found moderate level of correlation between them. In most of the similar studies, not GRSpain but visual analogue scale (VASpain) was used for the same purposes.7,12,15,16,35,39,43 Correlation between different translated versions of the NDI and VASpain varied from 0.4343 to 0.71.39 We found MDC equal to 5.4 points—close to the results, reported by Stratford et al for patients with neck pain (4.7), Vernon for patients with whiplash-associated disorders (5), Polish (5.96) and Japanese (6.8) versions of the NDI.6,13,44,45 It is higher in comparison with Greek version (1.78) and lower in comparison with results of Pool et al for neck pain group (10.5) and results of Cleland et al for cervical radiculopathy group (10.2).38,46,47 From our point of view, the last 3 studies, in reporting test-retest reliability, which applied the method of comparing first and second NDI scores in subjects who did not respond to treatment, are sufficiently dissimilar to ours as to make comparisons inappropriate. The finding of a 2-factor solution is in accord with 8 other studies,8,10,16,36–38,42,48,49 whereas 8 others have reported a 1factor solution.5–7,13,50–53 At this point in time, it seems that these variations in the factor structure of the NDI, as well as in the items that load onto the various 2-factor solutions, may best be understood as the result of cultural/linguistic differences among the samples studied. As with any cross-cultural validation study, replication of the NDI-RU in both similar and different Russian sociocultural milieus is recommended, especially to confirm and generalize our finding of a 2-factor solution to the NDI-RU. As such, we defer the determination of the constructs within these factors until this factor confirmation has occurred.

Limitations Our study has several limitations. First, representatives were predominantly urban citizens; an analogous study conducted in villagers may show different results. www.spinejournal.com

1119

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1119

19/06/15 10:19 AM

HEALTH SERVICES RESEARCH Sampling was made in a secondary level of medical care in a special center, which provides treatment basically with application of manual therapy, which has its limitations in elderly patients. Therefore, different results could be found in a primary care level. We exclude patients with acute neck trauma, for example, after whiplash injury. However, the characteristics of our sample and psychometric properties of the NDI-RU were found to be the same with those studies in which patients with acute neck trauma were included.3,16 Also, it was found that “patients with self-reported whiplash do not differ from patients with other painful neck complaints regarding pain, function, or prognosis.”54

CONCLUSION The Russian language version of the NDI resulted in a valid, reliable instrument that can be used both in clinical practice and in scientific investigations, including multicultural and multinational research projects.

➢ Key Points ‰ A newly devised Russian language version of the Neck Disability Index (NDI-RU) was applied to a sample of Russian-speaking patients with neck pain grades I–III. ‰ In this sample, it was found as a valid and reliable scale. ‰ Completion of the NDI-RU takes 3 to 4 minutes.

References

1. Murray CJ, Vos T, Lozano R, et al. Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012;380:2197–223. 2. Carroll LJ, Hogg-Johnson S, van der Velde G, et al. Course and prognostic factors for neck pain in the general population: results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders. Spine 2008;33:S75–82. 3. Vernon H, Mior S. The Neck Disability Index: a study of reliability and validity. J Manipulative Physiol Ther 1991;14:409–15. 4. Vernon H. The Neck Disability Index: state-of-the-art, 1991-2008. J Manipulative Physiol Ther 2008;31:491–502. 5. Shaheen AA, Omar MT, Vernon H. Cross-cultural adaptation, reliability, and validity of the Arabic version of neck disability index in patients with neck pain. Spine 2013;38:E609–15. 6. Nakamaru K, Vernon H, Aizawa J, et al. Crosscultural adaptation, reliability, and validity of the Japanese version of the neck disability index. Spine 2012;37:E1343–7. 7. Monticone M, Ferrante S, Vernon H, et al. Development of the Italian Version of the Neck Disability Index: cross-cultural adaptation, factor analysis, reliability, validity, and sensitivity to change. Spine 2012;37:E1038–44. 8. Uthaikhup S, Paungmali A, Pirunsan U. Validation of Thai versions of the Neck Disability Index and Neck Pain and Disability Scale in patients with neck pain. Spine 2011;36:E1415–21. 9. Wu S, Ma C, Mai M, et al. Translation and validation study of Chinese versions of the neck disability index and the neck pain and disability scale. Spine 2010;35:1575–9.

1120

NDI-RU: Adaptation, Validity, Reliability • Bakhtadze et al

10. Salo P, Ylinen J, Kautiainen H, et al. Reliability and validity of the Finnish version of the neck disability index and the modified neck pain and disability scale. Spine 2010;35:552–6. 11. Kesiktas N, Ozcan E, Vernon H. Clinimetric properties of the Turkish translation of a modified neck disability index. BMC Musculoskelet Disord 2012;13:25. 12. Misterska E, Jankowski R, Glowacki M. Cross-cultural adaptation of the Neck Disability Index and Copenhagen Neck Functional Disability Scale for patients with neck pain due to degenerative and discopathic disorders. Psychometric properties of the Polish versions. BMC Musculoskelet Disord 2011;12:84. 13. Guzy G, Vernon H, Polczyk R, et al. Psychometric validation of the authorized Polish version of the Neck Disability Index. Disabil Rehabil 2013;35:2132–7. 14. Jorritsma W, de Vries GE, Geertzen JH, et al. Neck Pain and Disability Scale and the Neck Disability Index: reproducibility of the Dutch Language Versions. Eur Spine J 2010;19: 1695–1701. 15. Jorritsma W, de Vries GE, Dijkstra PU, et al. Neck Pain and Disability Scale and Neck Disability Index: validity of Dutch language versions. Eur Spine J 2012;21:93–100. 16. Andrade Ortega JA, Delgado Martinez AD, Almecija RR. Validation of the Spanish version of the Neck Disability Index. Spine 2010;35:E114–8. 17. Hurwitz EL, Carragee EJ, van den Velde G, et al. Treatment of neck pain: noninvasive interventions: results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders. Spine 2008;33:S123–52. 18. Guzman J, Haldeman S, Carroll LJ, et al. Clinical practice implications of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders: from concepts and findings to recommendations. J Manipulative Physiol Ther 2009;32: S227–43. 19. Main CJ, Sullivan MJL, Watson J. Pain Management: Practical Applications of the Biopsychosocial Perspective. 2nd ed. London, UK: Churchill Livingstone Elsevier; 2008. 20. Ekblom A, Hansson P. Pain intensity measurements in patients with acute pain receiving afferent stimulation. J Neurol Neurosurg Psychiatry 1988;51:481–6. 21. Price DD, Bush FM, Long S, et al. A comparison of pain measurement characteristics of mechanical visual analogue and simple numerical rating scales. Pain 1994;56:217–26. 22. Guillemin F, Bombardier C, Beaton D. Cross-cultural adaptation of health-related quality of life measures: literature review and proposed guidelines. J Clin Epidemiol 1993;46:1417–32. 23. Beaton DE, Bombardier C, Guillemin F, et al. Guidelines for the process of cross-cultural adaptation of self-report measures. Spine 2000;25:3186–91. 24. Streiner DL, Norman GR. Health Measurement Scales. A Practical Guide to Their Development and Use. 3rd ed. New York, NY: Oxford University Press; 2003. 25. Headache Classification Subcommittee of the International Headache Society. The international classification of headache disorders: 2nd edition. Cephalalgia 2003;1:9–160. 26. Weir JP. Quantifying test-retest reliability using the intraclass correlation coefficient and the SEM. J Strength Cond Res 2005;19: 231–40. 27. Andresen EM. Criteria for assessing the tools of disability outcomes research. Arch Phys Med Rehabil 2000;81:S15–20. 28. Stratford PW. Getting more from the literature: estimating the standard error of measurement from reliability studies. Physiother Can 2004;56:27–30. 29. Terwee CB, Bot SD, de Boer MR, et al. Quality criteria were proposed for measurement properties of health status questionnaires. J Clin Epidemiol 2007;60:34–42. 30. Mokkink LB, Terwee CB, Patrick DL, et al. The COSMIN study reached international consensus on taxonomy, terminology, and definitions of measurement properties for health-related patientreported outcomes. J Clin Epidemiol 2010;63:737–45. 31. Mokkink LB, Terwee CB, Knol DL, et al. The COSMIN checklist for evaluating the methodological quality of studies on measurement

www.spinejournal.com

July 2015

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1120

19/06/15 10:19 AM

HEALTH SERVICES RESEARCH

32.

33. 34.

35. 36. 37. 38. 39.

40.

41. 42.

properties: a clarification of its content. BMC Med Res Methodol 2010;10:22. Mokkink LB, Terwee CB, Patrick DL, et al. The COSMIN checklist for assessing the methodological quality of studies on measurement properties of health status measurement instruments: an international Delphi study. Qual Life Res 2010;19:539–49. Schellingerhout JM, Heymans MW, Verhagen AP, et al. Measurement properties of translated versions of neck-specific questionnaires: a systematic review. BMC Med Res Methodol 2011;11:87. Schellingerhout JM, Verhagen AP, Heymans MW, et al. Measurement properties of disease-specific questionnaires in patients with neck pain: a systematic review. Qual Life Res 2012;21: 659–70. Kovacs FM, Bago J, Royuela A, et al. Psychometric characteristics of the Spanish version of instruments to measure neck pain disability. BMC Musculoskelet Disord 2008;9:42. Nieto R, Miro J, Huguet A. Disability in subacute whiplash patients: usefulness of the neck disability index. Spine 2008;33:E630–5. Telci EA, Karaduman A, Yakut Y, et al. The cultural adaptation, reliability, and validity of neck disability index in patients with neck pain: a Turkish version study. Spine 2009;34:1732–5. Trouli MN, Vernon HT, Kakavelakis KN, et al. Translation of the Neck Disability Index and validation of the Greek version in a sample of neck pain patients. BMC Musculoskelet Disord 2008;9:106. Mousavi SJ, Parnianpour M, Montazeri A, et al. Translation and validation study of the Iranian versions of the Neck Disability Index and the Neck Pain and Disability Scale. Spine 2007;32: E825–31. Yu L, Song Y, Yang X, et al. Systematic review and meta-analysis of randomized controlled trials: comparison of total disk replacement with anterior cervical decompression and fusion. Orthopedics 2011;34:e651–8. Takeshita K, Hosono N, Kawaguchi Y, et al. Validity, reliability and responsiveness of the Japanese version of the Neck Disability Index. J Orthop Sci 2012;18:14–21. Luksanapruksa P, Wathana-apisit T, Wanasinthop S, et al. Reliability and validity study of a Thai version of the Neck Disability Index in patients with neck pain. J Med Assoc Thai 2012;95:681–8.

Spine

NDI-RU: Adaptation, Validity, Reliability • Bakhtadze et al

43. Jorritsma W, Dijkstra PU, de Vries GE, et al. Detecting relevant changes and responsiveness of Neck Pain and Disability Scale and Neck Disability Index. Eur Spine J 2012;21:2550–7. 44. Stratford PW, Riddle DL, Binkley JM. Using the Neck Disability Index to make decisions concerning individual patients. Physiother Canada 1999;51:107–112. 45. Vernon H. Assessment of self-rated disability, impairment, and sincerity of effort in whiplash-associated disorders. J Musculoscelet Pain 2000;8:155–67. 46. Pool JJ, Ostelo RW, Hoving JL, et al. Minimal clinically important change of the Neck Disability Index and the Numerical Rating Scale for patients with neck pain. Spine 2007;32:3047–51. 47. Cleland JA, Fritz JM, Whitman JM, et al. The reliability and construct validity of the Neck Disability Index and patient specific functional scale in patients with cervical radiculopathy. Spine 2006;31:598–602. 48. Wlodyka-Demaille S, Poiraudeau S, Catanzariti JF, et al. French translation and validation of 3 functional disability scales for neck pain. Arch Phys Med Rehabil 2002;83:376–82. 49. Young SB, Aprill C, Braswell J, et al. Psychological factors and domains of neck pain disability. Pain Med 2009;10:310–8. 50. Cook C, Richardson JK, Braga L, et al. Cross-cultural adaptation and validation of the Brazilian Portuguese version of the Neck Disability Index and Neck Pain and Disability Scale. Spine 2006;31:1621–7. 51. Hains F, Waalen J, Mior S. Psychometric properties of the neck disability index. J Manipulative Physiol Ther 1998;21:75–80. 52. Pickering PM, Osmotherly PG, Attia JR, et al. An examination of outcome measures for pain and dysfunction in the cervical spine: a factor analysis. Spine 2011;36:581–8. 53. Gabel CP, Cuesta-Vargas AI, Osborne JW, et al. Confirmatory factory analysis of the Neck Disability Index in a general problematic neck population indicates a one-factor model. Spine J 2014;14:1410–16. 54. Verhagen AP, Lewis M, Schellingerhout JM, et al. Do whiplash patients differ from other patients with non-specific neck pain regarding pain, function or prognosis? Manual Ther 2011;16: 456–62.

www.spinejournal.com

1121

Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE140195_LR 1121

19/06/15 10:19 AM

The Neck Disability Index-Russian Language Version (NDI-RU): A Study of Validity and Reliability.

Cross-cultural adaptation and psychometric testing...
192KB Sizes 0 Downloads 11 Views