Validity of the Neck Disability Index and Neck Pain and Disability Scale for measuring disability associated with chronic, non-traumatic neck pain

The purpose of this study was to evaluate the construct and content validity of the Neck Disability Index (NDI) and the Neck Pain and Disability Scale (NPAD) in patients with chronic, non-traumatic neck pain. Twenty patients (mean age=64.5 years) completed a patient-specific questionnaire, the Problem Elicitation Technique (PET), followed by the NDI and NPAD. Content validity was assessed by comparing the items of the NDI and NPAD with problems identified from the PET. Construct validity of the fixed-item questionnaires was examined by establishing the correlation with each other, and with the PET score. Eleven common problems were identified by patients through the PET, of which six were included in the NDI and seven included in the NPAD. The NDI and NPAD scores were strongly correlated (r=0.86, p<0.01), while the correlation between the PET and the fixed-item questionnaires was moderate (NDI: r=0.62, p<0.01; NPAD: r=0.71, p<0.01). Both the NDI and the NPAD include most of the functional problems common to this patient group, and display good content validity. The PET is better able to evaluate the problems specific to the individual patient and is therefore measuring a somewhat different construct to the fixed-item questionnaires.     

The neck pain and disability scale: test-retest reliability and construct validity

OBJECTIVE: This research established test-retest reliability and construct validity for the Neck Pain and Disability Scale (NPAD). METHODS: Two groups of patients with neck pain completed the NPAD. The first group filled out the scale twice before treatment, whereas the second completed it with a number of other outcome measures once a month for 4 months, for evaluation of treatment with injections. RESULTS: The reliability coefficient (r2 = 0.93) calculated from the data for the first group of patients indicated high test-retest reliability. Construct validity was demonstrated with the second group when the NPAD was compared with a number of other pain measures and found to have a larger treatment effect. The Neck Pain and Disability Scale factor scores also indicated that treatment effects varied across the four factors. CONCLUSIONS: The NPAD is a stable and responsive measure for patients with neck pain. The Neck Pain and Disability Scale factor scores are useful in identifying treatment effects on the specific dimensions involved in the pain experience.     

A comparison of four disability scales for Turkish patients with neck pain.

OBJECTIVE: The Neck Disability Index, the Northwick Park Pain Questionnaire, the Copenhagen Neck Functional Disability Scale and the Neck Pain and Disability Scale are widely used scales for assessing neck pain or disability. The aim of this study was to determine the most suitable scale for Turkish patients with neck pain. METHODS: All scales were translated into Turkish, administered to 102 patients with neck pain, then compared with regard to their construct validity, reliability, responsiveness, acceptability and usefulness. RESULTS: The scales were similar in their high validity, reliability standards and sensitivity to change, but differed in their acceptability and usefulness. The item about driving in the Neck Disability Index and the Northwick Park Pain Questionnaire was omitted by 69.6% of patients for reasons other than a neck problem. CONCLUSION: All scales were reliable, valid and sensitive instruments, with similar psychometric properties. The scale that most adequately reflects the patient should be chosen.     

Confirmatory Factor Analysis,Reliability, and Validity of the Persian Version of the Coping Strategies Questionnaire for Iranian People With Nonspecific Chronic Neck Pain

ObjectiveThe purpose of this study was to assess the reliability and construct validity of, and perform confirmatory factor analysis of, the Persian version of the Coping Strategies Questionnaire (CSQ) for Iranian people with nonspecific chronic neck pain.MethodsWe performed psychometric testing of the Persian version of the Coping Strategies Questionnaire. Participants were 123 native Persian speakers with chronic neck pain lasting at least 3 months. They were between 18 and 55 years old. The CSQ was administered by self-report. After 5 to 7 days, 94 participants completed the questionnaire in the retest session. Confirmatory factor analysis was done to assess the model fit (χ² test, comparative fit index, and root-mean-square error of approximation) of the 7-factor solution of the Persian version of the CSQ. The Cronbach α was used for internal consistency; intraclass correlation coefficient, standard error of measurement, and minimal detectable change for reliability; and nonparametric tests of group differences and correlations for construct validity. To assess the construct validity, we examined the ability of the CSQ to discriminate people based on sex, level of education, and physical activity. Correlations with the Short Form Health Survey (SF-12), Tampa Scale for Kinesiophobia, visual analog scale, Fear-Avoidance Beliefs Questionnaire, Pain Catastrophizing Scale, and Neck Disability Index were also determined to test the validity.ResultsConfirmatory factor analysis measures—χ² test, comparative fit index, and root-mean-square error of approximation—were 1.72, 0.76, and 0.07, respectively. Internal consistency was excellent (0.85). All intraclass correlation coefficients were above the acceptable level of 0.70, with the highest reliability obtained for the Praying subscale in both test and retest sessions. The standard error of measurement for the CSQ total score was 2.26, and the minimal detectable change was 6.25. The Cronbach α for the total score and for the subscales ranged from 0.75 to 0.93. Scores of the subscales of the CSQ and other questionnaires showed low correlation except for the physical component of the SF-12. The Catastrophizing subscale had a positive correlation with the Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Fear-Avoidance Beliefs Questionnaire, and Neck Disability Index, and a negative correlation with the SF-12.ConclusionThe CSQ has acceptable and good measurement properties to assess coping strategies in Iranian people with nonspecific chronic neck pain. It is a reliable measure, though, for validity only The Catastrophizing subscale showed significant correlation with other scales, but the findings should be interpreted with caution because of the limitations of the study.     

Reliability and validity of the Hindi version of the Neck Pain and Disability Scale in cervical radiculopathy patients

PURPOSE: To assess the reliability and validity of the Neck Pain and Disability Scale (NPAD) translated into Hindi. METHOD: Following a pilot study to ascertain uncertainties with existing terminology in the NPAD scale, a cervical radiculopathy patient cohort (n = 63) was assessed with the translated NPAD. Reliability was assessed by regression analysis for test-retest and by item-factor and factor-total score correlations. Face validity was compared in a cross-sectional design study with an asymptomatic group (n = 38). Convergent and divergent validity were investigated by correlating the NPAD scores with the Numerical Pain Rating Scale (NPRS) for neck and arm pain, and 10 cm long VAS Activity and VAS Depression scales. RESULTS: ICC values for test-retest NPAD total and factor scores were >0.92 and R2 values >0.912. Pearson product moment correlation of item vs. factor scores varied from 0.17 - 0.91 and for factor vs. total scores 0.72 - 0.91. Differences in NPAD scores between the patient and the asymptomatic group were significant (t = 30.90, p < 0.05). Convergent validity was explained when Factor 2 (minus item 20) was correlated (r = 0.67) with NPRS maximum value scores. Divergent validity was illustrated by low correlation with VAS Activity (r = 0.15) and negative correlation with VAS Depression (r = -0.80) scores. CONCLUSION: Based on the results of this study, the Hindi version of the NPAD is a reliable and valid instrument for the assessment of pain and disability in cervical radiculopathy patients.     

Transcultural adaptation and validation of Hindi version of Quebec Back Pain Disability Scale

Abstract

Purpose: To transculturally adapt the Quebec Back Pain Disability Scale for Hindi-speaking population and examine its psychometric properties in patients with low back pain.

Materials and methods: The Quebec Back Pain Disability Scale was translated and cross-culturally adapted into Hindi following international guidelines. Hindi version of the scale was completed by 120 patients with low back pain and 60 healthy controls. Patients with low back pain were also administered the Hindi-Roland Morris Disability Questionnaire and Visual Analog Scale. Psychometric evaluation included test–retest reliability, convergent and discriminative validity. Exploratory factor analysis was carried out to determine the factor structure.

Results: The factorial analysis revealed a four-factor solution (bending/carrying, ambulation/reach, prolonged postures and rest). Convergent validity was confirmed by high correlation of Hindi Quebec Back Pain Disability Scale to the Hindi version of Roland Morris Disability Questionnaire (r?=?0.77 and p?<?0.001) as well as Visual Analog Scale (r?=?0.682 and p?<?0.001) scores. Discriminative validity was established by significantly different scores for patients with low back pain and the healthy controls (35.36?±?18.6 vs. 9.13?±?6.08 and p?<?0.001). The translated version of the scale showed remarkable internal consistency (Cronbach α?=?0.98) and the intraclass correlation coefficient of test–retest reliability was excellent (ICC_2,1=0.96). MDC₉₅ and SEM scores obtained were 10.28 and 3.71, respectively.

Conclusion: The Hindi version of Quebec Back Pain Disability Scale has good test–retest reliability, discriminative and convergent validity and is appropriate for clinical and research use in Hindi-speaking low back pain patients.

• Implications for rehabilitation

• Linguistically and culturally adapted questionnaires help researchers make adequate inferences about instruments measuring health and quality of life.

• The translated version would serve as a valid research tool allowing comparability of data across cultures thus, providing opportunities for large multicenter, multicountry trials.

• A Hindi Quebec Back Pain Disability Scale version will help to improve the quality and efficacy of assessment of low back pain by developing in patients, a better understanding of the items which can be easily correlated with the activities of daily living.

     

Assessment of pain and disability in patients with chronic neck pain: reliability and construct validity of the Turkish version of the neck pain and disability scale

OBJECTIVES: The objective of this study was to test whether a Turkish version of the Neck Pain and Disability Scale retains its reliability and validity of the original English version. METHODS: Sixty-one patients with chronic neck pain were enrolled in the study. The Neck Pain and Disability Scale (NPDS), the Pain Disability Index (PDI) and The Hospital Anxiety and Depression Scale (HADS) were filled by all subjects. Reliability was determined by internal consistency. Internal consistency was measured by calculating Cronbach's alpha and item-total correlation. Validity was examined by correlating the NPDS scores to the Visual Analogue Scale (VAS), PDI and HADS scores. RESULTS: Cronbach's alpha value for NPDS was found to be 0.86 and this was statistically significant (p<0.0001). The item-total correlations of NPDS varied between 0.08 and 0.69. The cross-sectional construct validity coefficients were 0.51 for PDI, 0.45 for VAS, 0.35 and 0.33 for Hospital Anxiety and Depression Scales. CONCLUSION: Despite its major limitations, our results seem to support previous findings of the English and French versions of the Neck Pain and Disability Scale, indicating that this functional scale is valid and reliable.     

The Nordic Musculoskeletal Questionnaire: cross-cultural adaptation into Turkish assessing its psychometric properties

Purpose: The purpose of this study was to linguistically and culturally adapt the Nordic Musculoskeletal Questionnaire (NMQ) for use in Turkey, and to examine the psychometric properties of this adapted version.

Method: The cross-cultural adaptation was achieved by translating the items from the original version, with back-translation performed by independent mother-tongue translators, followed by committee review. Reliability (internal consistency and test–retest) was examined for 198 participants who completed the NMQ twice (with a 1 week interval). Construct validity was examined with data from 126 participants from the same population, who completed further four questionnaires related to the body regions described in the NMQ.

Results: The internal consistency was excellent (Cronbach’s alpha?=?0.896). The test–retest reliability was examined with the prevalence-adjusted bias-adjusted kappa (PABAK) and all items showed moderate to almost perfect reliability (PABAK?=?0.57–0.90). Participants with a musculoskeletal problem in a related region had significantly more disability/pain, as assessed by the relevant questionnaires (p?Conclusions: This study provided considerable evidence that the Turkish version of the NMQ has appropriate psychometric properties, including good test–retest reliability, internal consistency and construct validity. It can be used for screening and epidemiological investigations of musculoskeletal symptoms.

• Implications for Rehabilitation

• The Nordic Musculoskeletal Questionnaire (NMQ) can be used for the screening of musculoskeletal problems.

• The NMQ allows comparison of musculoskeletal problems in different body regions in epidemiological studies with large numbers of participants.

• The Turkish version of the NMQ can be used for rehabilitation due to its appropriate psychometric properties, including good test–retest reliability, internal consistency and construct validity.

     

Prospective Cohort Study of Patients With Neck Pain in a Manual Therapy Setting: Design and Baseline Measures

ObjectivesThe purpose of this study was to describe the design and baseline measurements of a prospective multicenter cohort study in patients with neck pain treated by Dutch manual therapists. Objectives of the study were to determine which patients seek help from a manual therapist, to describe usual care manual therapy in patients with neck pain, to examine the occurrence of nonserious adverse events after treatment, to describe predictors of adverse events, and to determine whether the occurrence of nonserious adverse events affect outcome after manual therapy care.MethodsDuring a 3-month inclusion period, consecutive patients aged between 18 and 80 years presenting with neck pain in manual therapy practices in The Netherlands were included in the study. Baseline questionnaires included the Numeric Rating Scale, Neck Disability Index (NDI), Neck Bournemouth Questionnaire, Fear Avoidance Beliefs Questionnaire (FABQ), and Patient Expectancy List. Within the treatment episode, manual therapist clinical reasoning and applied interventions were registered and patients reported on adverse events. At the end of the treatment episode and at 12-month follow-up, pain intensity (Numeric Rating Scale), functional outcomes (NDI, Neck Bournemouth Questionnaire), personal factors (FABQ), and global perceived effect were measured.ResultsDuring the 3-month inclusion period, 263 participating manual therapists collected data on 1193 patients with neck pain. Most patients (69.4%) were female. The mean age was 44.7 (±13.7) years. The NDI showed overall mild disability (mean score 26%). Mean scores in pain intensity were moderate (4.8), and there was low risk of prolonged disability owing to personal factors (FABQ).ConclusionThis study provides information on baseline characteristics of patients visiting manual therapists for neck pain. In The Netherlands, patients seeking care of manual therapists are comparable to patients in other countries regarding demographics and neck pain characteristics.     

Development of a short version of the Neck Pain and Disability Scale

Previous evaluations of the 20‐item Neck Pain and Disability Scale (NPAD) were indicative of excessive redundancy of the measure. The aim of this study was to develop a shortened version of the NPAD (sf‐NPAD) based on results of item‐to‐total‐score correlations and factor analysis as published by the developers of the original NPAD. Two items with the highest item‐to‐total score correlation were selected per factor subscale with the exception of one factor consisting of only one item. This resulted in the selection of 9 items for the sf‐NPAD. The sf‐NPAD was validated in a separate sample of 448 neck pain patients from 15 general practices in the area of Göttingen/Germany. Participants completed the 20‐item NPAD German version and gave additional sociodemographic and clinical information. Psychometric properties of the sf‐NPAD were evaluated using Cronbach's alpha, item‐to‐total‐score correlation, and unrestricted principal factor analysis. Construct validity was evaluated by Pearson's r with clinical characteristics. Discriminative validity was examined by comparing differences between subgroups stratified by psychosocial characteristics using t‐tests for mean scores. Cronbach's alpha of the sf‐NPAD was 0.88. Item‐to‐total‐scale correlations ranged between 0.628 and 0.815, and sf‐NPAD items homogeneously loaded on a single factor. Correlation analysis showed high correlations with criterion variables. The sf‐NPAD scores of patient subgroups were significantly different showing good discriminative validity. In conclusion, the sf‐NPAD demonstrated good validity and internal consistency in this general practice setting. The abbreviated version may facilitate applicability of the scale in clinical and research settings.     

Reliability and Responsiveness of Patient-Reported Outcome Measures of Neck Disability to Physical Therapy: Comparison of the Copenhagen,Northwick Park,and Neck Bournemouth Questionnaires and the Neck Disability Index

ObjectiveThe purpose of this study was to identify the external and internal reliability and responsiveness of the validated patient-reported outcome measures (PROMs) of neck pain to a standardized regimen of physiotherapy administered acutely after mild whiplash injury using the clinically significant improvement components of the Patient Global Impression of Change (PGIC) as the outcome measure.MethodsEighty-six patients with neck pain alone were referred for physiotherapy within 2 weeks of whiplash injury. They completed the Copenhagen, Northwick Park (NP), and Neck Bournemouth (NBQ) questionnaires and the Neck Disability Index (NDI) before starting and after treatment when they also completed the PGIC. Treatment comprised deep soft tissue massage, myofascial releases, muscle energy techniques, joint articulation and manipulation techniques, and a home exercise program. The duration of treatment was between 3 and 6 weeks. A PGIC of 6 or 7 was considered to be clinically significant improvement.ResultsThe external reliability of the PROMs was >0.7 and internal >0.87. All components of the PROMs contributed to the final score except headache in the Copenhagen and upper-limb dysesthesia in the NP. The most reliable questionnaire was the NBQ, which was significantly more responsive than the Copenhagen (P = .008). The NBQ was slightly more responsive than the NDI and NP. The NBQ and NDI were successfully completed more frequently than the NP and Copenhagen.ConclusionThe NP, NDI, and NBQ are all reliable and responsive measures of change after physiotherapy for neck pain after acute whiplash injury.     

Reliability and validity of the Hindi version of the Neck Pain and Disability Scale in cervical radiculopathy patients

Purpose. To assess the reliability and validity of the Neck Pain and Disability Scale (NPAD) translated into Hindi.

Method. Following a pilot study to ascertain uncertainties with existing terminology in the NPAD scale, a cervical radiculopathy patient cohort (n = 63) was assessed with the translated NPAD. Reliability was assessed by regression analysis for test-retest and by item-factor and factor-total score correlations. Face validity was compared in a cross-sectional design study with an asymptomatic group (n = 38). Convergent and divergent validity were investigated by correlating the NPAD scores with the Numerical Pain Rating Scale (NPRS) for neck and arm pain, and 10 cm long VAS Activity and VAS Depression scales.

Results. ICC values for test-retest NPAD total and factor scores were >0.92 and R² values >0.912. Pearson product moment correlation of item vs. factor scores varied from 0.17 – 0.91 and for factor vs. total scores 0.72 – 0.91. Differences in NPAD scores between the patient and the asymptomatic group were significant (t = 30.90, p < 0.05). Convergent validity was explained when Factor 2 (minus item 20) was correlated (r = 0.67) with NPRS maximum value scores. Divergent validity was illustrated by low correlation with VAS Activity (r = 0.15) and negative correlation with VAS Depression (r = ?0.80) scores.

Conclusion. Based on the results of this study, the Hindi version of the NPAD is a reliable and valid instrument for the assessment of pain and disability in cervical radiculopathy patients.     

Management of acute neck pain: A case series describing immediate and short term clinical outcomes following use of the Multifidus Isometric Technique

BackgroundAcute facet capsular entrapment results in sudden onset of pain and reduced ability to perform active cervical motions. The Multifidus Isometric Technique (MIT) is a type of manual therapy intervention theorized to target the entrapped facet capsule and pull the entrapped synovial folds from the facet joint resulting in decreased pain and increased function.PurposeTo describe immediate MIT clinical outcomes for patients with acute neck pain.MethodsConsecutive patients (n = 30; 70% female) with sudden onset of neck pain received MIT within 48 hours of symptom onset. Clinical outcome measures included: 1) 11-point Numeric Pain Rating Scale (NPRS); 2) cervical AROM, and 3) the Neck Disability Index (NDI). Paired-sample t-testing was used to assess for within and between-session changes in outcome measure scores.ResultsWithin-session NPRS improvements were observed during all cervical AROM movements (p < .01), with initial treatment associated with greater improvements on average (M = 2.4 ± 1.6 points) compared to the second treatment (M = 0.6 ± 0.9 points). Similarly, most within-session AROM measures improved during both sessions (p < .01) with greater average improvements observed following the initial treatment session and for cervical rotation to the symptomatic side (M = 26.5 ± 9.6 vs. 8.0 ± 9.7°). Between-session NDI scores improved (M = 15.3 ± 9.8, p < .01) with approximately 60% of patients achieving a minimally clinically important difference of 14 percentage points.DiscussionThe MIT is a potentially beneficial intervention for patients with acute neck pain. Future studies consisting of longer follow-up time points and comparison treatment groups are needed to test MIT effectiveness.     

Assessment of pain and disability in patients with chronic neck pain: reliability and construct validity of the Turkish version of the neck pain and disability scale

Objectives:?The objective of this study was to test whether a Turkish version of the Neck Pain and Disability Scale retains its reliability and validity of the original English version.

Methods:?Sixty-one patients with chronic neck pain were enrolled in the study. The Neck Pain and Disability Scale (NPDS), the Pain Disability Index (PDI) and The Hospital Anxiety and Depression Scale (HADS) were filled by all subjects. Reliability was determined by internal consistency. Internal consistency was measured by calculating Cronbach's alpha and item-total correlation. Validity was examined by correlating the NPDS scores to the Visual Analogue Scale (VAS), PDI and HADS scores.

Results:?Cronbach's alpha value for NPDS was found to be 0.86 and this was statistically significant (p?<?0.0001). The item-total correlations of NPDS varied between 0.08 and 0.69. The cross-sectional construct validity coefficients were 0.51 for PDI, 0.45 for VAS, 0.35 and 0.33 for Hospital Anxiety and Depression Scales.

Conclusion:?Despite its major limitations, our results seem to support previous findings of the English and French versions of the Neck Pain and Disability Scale, indicating that this functional scale is valid and reliable.     

Cranio-cervical flexor muscle impairment at maximal, moderate, and low loads is a feature of neck pain

Impairment of the cranio-cervical flexor (CCF) muscles is a feature of painful cervical spine disorders. The aim of this study was to investigate if CCF muscle impairment is present over a range of contraction intensities (maximal, moderate, low) in neck pain sufferers compared to individuals with no history of neck pain. Isometric CCF muscle strength (isometric maximal voluntary contraction (MVC)), and endurance at moderate (50% of MVC), and low (20% of MVC) loads was compared in 46 participants with neck pain (Neck Disability Index (NDI): mean+/-SD; 22.8+/-5.2) and 47 control participants (NDI: 2.6+/-2.6). Compared to the control group, the neck pain group had a significant deficit (15.9%, P=0.037) in their MVC peak torque recordings, as well as a significantly reduced capacity to sustain isometric CCF muscle contractions to task failure at 20% of MVC (35% deficit, P=0.03) and 50% of MVC (27% deficit, P=0.002). Neck pain participants also demonstrated poorer accuracy in maintaining their MVC(20) contraction at the nominated isometric CCF torque amplitude (P=0.02), compared to control participants. It would appear that impairment in isometric CCF muscle performance exists over a range of contraction intensities in neck pain sufferers, which may benefit from specific therapeutic intervention.     

The ProFitMap-neck – reliability and validity of a questionnaire for measuring symptoms and functional limitations in neck pain

Purpose: To assess overall reliability and validity of a neck-specific questionnaire, the Profile Fitness Mapping neck questionnaire (ProFitMap-neck), on three chronic neck pain groups. Method: Participating groups were as follows: whiplash associated disorders, inpatient care (IP-WAD, n?=?127); nonspecific neck pain, inpatient care (IP-NS, n?=?83) and nonspecific neck pain subjects (non-IP-NS, n?=?104). All groups answered the ProFitMap-neck and the SF-36, whereas non-IP-NS also answered the Neck Disability Index (NDI) and the Functional Self-Efficacy Scale (SES). Internal consistency, test–retest reliability and components of convergent construct, face and content validity were determined for the ProFitMap-neck. Results: The ProFitMap-neck showed good internal consistency in all three groups, and ICC test–retest reliability (0.80–0.91). Good correlation (0.66–0.78) and highest agreement was reached with NDI. According to the International Classification of Functioning, Disability and Health, the symptom scale of the ProFitMap-neck was mainly classified to the domain of impairments–body functions, and the functional limitation scale to the activity limitation domain. Conclusion: The results indicate that the ProFitMap-neck is valid for measuring symptoms and functional limitations in people with chronic neck pain. The combination of a composite total score of symptoms and function as well as separate scores of each domain makes ProFitMap-neck suitable for research as well as in clinical practice.

Implications for Rehabilitation

• The ProFitMap-neck can be used as a valid self-assessment tool for measuring symptoms and functional limitations in people belonging to the most prevalent categories of neck pain.

• The combination of the symptom and functional limitation questionnaire scores in a total score can be used for an overall clinical judgment.

     

French translation and validation of 3 functional disability scales for neck pain

OBJECTIVE: To translate and assess the reliability and the construct validity of 3 functional disability scales for neck pain. DESIGN: Reliability and validity study. SETTING: Tertiary care teaching hospital and outpatient clinic. PARTICIPANTS: One hundred one patients (mean age, 49 y). INTERVENTION: French translations were obtained by using the "translation-backward translation" method. Adaptations were made after a pilot study. MAIN OUTCOME MEASURES: Impairment outcome measures (visual analog scale [VAS] pain, neck range of motion, morning stiffness, score of neck sensitivity, radiologic score of Kellgren) and patients' perceived handicap (VAS) were recorded at the baseline visit. Three functional disability scales (Neck Disability Index [NDI], Neck Pain and Disability Scale [NPDS], Northwick Park Neck Pain Questionnaire [NPQ]) were recorded twice, at baseline visit and 24 hours later. Reliability was assessed by using the intraclass correlation coefficient (ICC) and the Bland and Altman method. Construct (convergent and divergent) validity was investigated by using the Spearman rank correlation coefficient and a factor analysis was performed. RESULTS: Test-retest was excellent for the NPDS and NDI (ICC =.91,.93, respectively) and good for the NPQ (ICC =.84). The Bland and Altman method showed no systematic trend. Expected convergent and divergent validity were observed only for the NPDS; 3 main factors were extracted by factor analysis and explained 78% of the cumulative variance. CONCLUSION: The 3 translated scales are valid, but the NPDS seems to have the best construct validity.     

The validity and reliability of the Turkish version of short‐form McGill Pain Questionnaire in patients with leukemia

Aims and objectives. To assess reliability and validity of the Turkish version of the Short‐form McGill Pain Questionnaire. Background. Pain is one of the most frequent and significant problems encountered by nurses practice across the world. The Short‐form McGill Pain Questionnaire was widely translated and used to assess the pain experience of several types of patients because it combines the properties of the standard McGill Pain Questionnaire but takes substantially less time to administer. Design. The study used psychometric testing to establish reliability and validity of the Turkish version of Short‐form McGill Pain Questionnaire. Methods. A convenience sample of 160 patients with leukaemia in Turkey was used to collect data regarding pain evaluation. The original version of the Short‐form McGill Pain Questionnaire, adapted into Turkish, was tested for internal consistency, content validity, construct validity and concurrent validity. Results. Internal consistency was found adequate at both assessments with Cronbach’s α 0·88 for test and 0·91 for retest. For reliability of the total, sensory, affective and evaluative total pain intensity, high intraclass correlations were demonstrated (0·85, 0·84, 0·82 and 0·70, respectively). Correlation of total, sensory and affective score with the numerical rating scale was tested for construct validity demonstrating r = 0·61 (p < 0·01) for test and r = 0·68 (p < 0·01) for retest. Correlation with blood pressure values for concurrent validity was found to be r = 0·78 (p < 0·001) for test and r = 0·73 (p < 0·001) for retest. Conclusion. Turkish version of the Short‐form McGill Pain Questionnaire has shown statistically acceptable levels of reliability and validity for pain evaluation in patients with leukaemia. Relevance to clinical practice. This study provided evidence that the Turkish version of the Short‐form McGill Pain Questionnaire is a reliable and valid instrument for assessing pain. This scale can be used to assess nursing interventions aimed at decreasing pain and efficacy of the treatment.     

Psychometric properties of the neck disability index amongst patients with chronic neck pain using item response theory

Objective: The Neck Disability Index (NDI) is commonly used for clinical and research assessment for chronic neck pain, yet the original version of this tool has not undergone significant validity testing, and in particular, there has been minimal assessment using Item Response Theory. The goal of the present study was to investigate the psychometric properties of the original version of the NDI in a large sample of individuals with chronic neck pain by defining its internal consistency, construct structure and validity, and its ability to discriminate between different degrees of functional limitation.

Methods: This is a cross-sectional cohort study of 585 consecutive patients with chronic neck pain seen in a university hospital rehabilitation clinic. Internal consistency was evaluated using Cronbach’s alpha, construct structure was evaluated by exploratory factor analysis, and discrimination ability was determined by Item Response Theory.

Results: The NDI demonstrated good internal consistency assessed by Cronbach’s alpha (0.87). The exploratory factor analysis identified only one factor with eigenvalue considered significant (cutoff 1.0). When analyzed by Item Response Theory, eight out of 10 items demonstrated almost ideal difficulty parameter estimates. In addition, eight out of 10 items showed high to perfect estimates of discrimination ability (overall range 0.8 to 2.9).

Conclusions: Amongst patients with chronic neck pain, the NDI was found to have good internal consistency, have unidimensional properties, and an excellent ability to distinguish patients with different levels of perceived disability.

• Implications for Rehabilitation

• The Neck Disability Index has good internal consistency, unidimensional properties, and an excellent ability to distinguish patients with different levels of perceived disability.

• The Neck Disability Index is recommended for use when selecting patients for rehabilitation, setting rehabilitation goals, and measuring the outcome of intervention.

     

Psychometric properties of the Neck Disability Index and Numeric Pain Rating Scale in patients with mechanical neck pain

Cleland JA, Childs JD, Whitman JM. Psychometric properties of the Neck Disability Index and numeric pain rating scale in patients with mechanical neck pain.

Objective

To examine the psychometric properties including test-retest reliability, construct validity, and minimum levels of detectable and clinically important change for the Neck Disability Index (NDI) and the numeric rating scale (NRS) for pain in a cohort of patients with neck pain.

Design

Single-group repeated-measures design.

Setting

Outpatient physical therapy (PT) clinics.

Participants

Patients (N=137) presenting to PT with a primary report of neck pain.

Interventions

Not applicable.

Main Outcome Measures

All patients completed the NDI and the NRS at the baseline examination and at a follow-up. At the time of the follow-up, all patients also completed the global rating of change, which was used to dichotomize patients as improved or stable. Baseline and follow-up scores were used to determine the test-retest reliability, construct validity, and minimal levels of detectable and clinically important change for both the NDI and NRS.

Results

Test-retest reliability was calculated using an intraclass correlation coefficient (ICC) (NDI ICC=.50; 95% confidence interval [CI], .25-.67; NRS ICC=.76; 95% CI, .51-.87). The area under the curve was .83 (95% CI, .75-.90) for the NDI score and .85 (95% CI, .78-.93) for the NRS score for determining between stable and improved patients. Thresholds for the minimum clinically important difference (MCID) for the NDI were 19-percentage points and 1.3 for the NRS.

Conclusions

Both the NDI and NRS exhibit fair to moderate test-retest reliability in patients with mechanical neck pain. Both instruments also showed adequate responsiveness in this patient population. However, the MCID required to be certain that the change in scores has surpassed a level that could be contributed to measurement error for the NDI was twice that which has previously been reported. Therefore the ongoing analyses of the properties of the NDI in a patient population with neck pain are warranted.