Translation and validation of the Persian version of ...

Manual Therapy 20 (2015) 850e854

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Original article

Translation and validation of the Persian version of the STarT Back Screening Tool in patients with nonspecific low back pain Mohsen Abedi a, Farideh Dehghan Manshadi a, *, Minoo Khalkhali a, Seyed Javad Mousavi b, Alireza Akbarzadeh Baghban c, Ali Montazeri d, Mohamad Parnianpour e a

Physiotherapy Department, School of Rehabilitation Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran Arthritis and Musculoskeletal Research Group, Faculty of Health Sciences, The University of Sydney, Sydney, Australia Proteomics Research Center, School of Rehabilitation Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran d Department of Mental Health, Iranian Institute for Health Sciences Research, Tehran, Iran e Department of Industrial Engineering & Manufacturing, University of Wisconsin Milwaukee, WI, USA b c

a r t i c l e i n f o

a b s t r a c t

Article history: Received 3 November 2014 Received in revised form 30 March 2015 Accepted 7 April 2015

Objective: To translate the STarT Back Screening Tool (SBT) into Persian and to investigate the psychometric properties of the new version in a group of patients with Non-Specific Low Back Pain (NSLBP). Background: The STarT is a validated questionnaire used for subgrouping LBP patients at three levels of low-, medium-, and high-risk, based on the risk of chronicity. It has previously been translated and validated in different languages. Methods: The translation and validation of the original questionnaire were carried out in accordance with the standard guidelines. To approve the construct validity, 295 patients with NSLBP completed a questionnaire package. The package comprised of the STarT, RolandeMorris Disability questionnaire (RMDQ), Tampa Scale for Kinesiophobia (TSK), Coping Strategies Questionnaire (CSQ), and Hospital Anxiety and Depression Scale (HADS). To evaluate test-retest reliability, 35 randomly selected NSLBP patients completed the STarT questionnaire within min. 24-hour interval. Results: Factor analysis confirmed two subscales of the STarT. The Cronbach a was .83 and .81 for the STarT and the subscale, respectively. This questionnaire showed excellent test-retest reliability (ICC ¼ .85) (p < 0.01). The correlations between the STarT and RMDQ, CSQ, TSK, and the two subscales of HADS were estimated to be .81, .70, .71, .74, and .71, respectively. The Area under the Curve was also calculated for 6 items and the range was between .734 and .860. Conclusions: The Persian version of the STarT is reliable and valid, and consistent with the original questionaire. Therefore, clinicians to subgroup Persian-speaking NSLBP patients can use it. © 2015 Elsevier Ltd. All rights reserved.

Keywords: Validation STarT Back Screening Tool Nonspecific low back pain

1. Introduction The existing guidelines suggest a diagnostic classification for subgrouping patients with low back pain into three groups: first, low back pain, caused by red flags such as tumor, infection, or serious medical diseases (2%), second, nerve root compression (10%), and third, non-specific low back pain (85%e90%) (Liebenson, 2007).

* Corresponding author. E-mail address: [email protected] (F.D. Manshadi).

Non Specific Low Back Pain (NSLBP) is a major health problem in both developed and developing countries (Fairbank et al., 2011). Iran, as a developing country, currently witnesses the prevalence of LBP in general population, working population, school children, and pregnant women ranging from 14.4% to 84.1% (Mousavi et al., 2006). The majority of LBP patients are categorized as NSLBP, yet this large group is not homogenous and includes patients with various signs and symptoms (Kent & Keating, 2005; Hall et al., 2009). Thus, it seems necessary to classify NSLBP patients into subgroups to improve the outcomes of the treatment (Kent et al., 2010). So far, a number of tools have been developed for classifying and subgrouping the NSLBP patients. The proposes of these systems, as reported, are diagnosis, prognosis, or treatment of patients with

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M. Abedi et al. / Manual Therapy 20 (2015) 850e854

LBP, but many of them are so complex that it is utterly difficult, if not impossible, to use them in physiotherapy clinics (Kamper et al., 2010). In 2008, Hill et al. developed a very simple and practical questionnaire (Hill et al., 2008). The STarT Back Screening Tool (STarT) is a nine-item questionnaire to subgroup LBP patients into three levels: low, medium, and high risk. This classification is based on mechanical and psychological factors that are detectable all through the questions. Low risk patients are those who have very little physical and psychological factors. The only recommendation for the patients of this group is giving advice. Patients who are at medium risk level and have some physical and psychological risk factors are referred to physiotherapy. Eventually, patients at high risk level suffer from very poor prognosis and need physiotherapy and cognitive behavior therapy. The results of a study demonstrated that subgrouping LBP patients with STarT questionnaire had considerably better outcomes compared to those of the current treatments (Hill et al., 2011). Many studies have stated that this tool is very useful and simple for clinical application, especially in physiotherapy clinics, and comparatively, it is more efficient than other tools (Fritz et al., 2011; Hill et al., 2010; Wideman et al., 2012). In one study, 214 LBP patients were referred to physiotherapy and were subgrouped into three levels in initial evaluation making use of STarT questionnaire. Clinical outcomes such as pain intensity and disability were collected at each physiotherapy session. The results showed that such classification provided better prognostic information for the physiotherapists and positively influenced the outcomes (Fritz et al., 2011). In another study, subgrouping of LBP patients by STarT questionnaire was compared with that of clinical experts. The results revealed that there was inconsistency in clinical experts' classification. In classification with STarT, a formal and systematic method for subgrouping was used which led to consistency in procedure and thus findings, whereas clinical experts only used intuition to classify their patients (Hill et al., 2010). Yet, in another study, STarT tool was administered to 300 patients along with some other questionnaires in the first session and also 4 months later. The results showed that the STarT could predict treatment-related changes. So, reduction in STarT scores predicted meaningful improvement on all dependent variables. The findings suggested that STarT questionnaire can be used as a more efficient tool to measure recovery from back pain compared with the other questionnaires (Wideman et al., 2012). All in all, the related literature suggest the significance of the questionnaire in the field of Physiotherapy leading the researchers to carrying out a study to translate the English version of the StarT questionnaire into Persian language and to investigate its psychometric properties in a sample of NSLBP patients. This version will be known as STarT-PE when the validation is accomplished. 2. Methods 2.1. Translation and cultural validation The translation and cultural adaptation processes were carried out according to the standard guidelines (Beaton et al., 2000; Plichta et al., 2012). First, contacts were made with the developers and permission to translate the questionnaire was obtained. To follow the guidelines, two independent professional translators were invited to translate STarT from English into Persian. One translator had knowledge of the STarT concepts and the other did not. The two translations were then compared and contrasted by the two translators resulting in a single consent version of the questionnaire. Next, two other professional translators who were

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totally blind to the original version, were asked to translate the new Persian questionnaire back into English. Finally, an expert committee consisting of the translators, the researchers, one clinical physiotherapist, and one methodologist reviewed all the translation and cultural adaptation processes. When consensus was reached, a prefinal version of the questionnaire was obtained. To achieve a final version of the questionnaire, face validity procedure was carried out with 35 NSLBP patients who referred to physiotherapy clinics. In the presence of one of the researchers, the prefinal version of the questionnaire was completed by the patients. The purpose was to make sure the Persian version of the questionnaire could be understood and to ascertain the questions measured what they were intended to measure. The patients were encouraged to ask about and discuss any item that seemed confusing. The findings were assessed by the researchers and then the final version of Persian questionnaire was developed. 2.2. Psychometric validation 2.2.1. Patients A total of 295 Persian-speaking patients with NSLBP who were referred to the physiotherapy clinics of three hospitals in Tehran over a period of six months were included in the study. Only the patients who had LBP with non-defined pathology and whose pain continued for a minimum of three months were considered as final participants (Fritz et al., 2007). The patients were 20 years or older and could read and understand Persian. Patients with severe back radiculopathy or other conditions such as tumors, fractures, pregnancy, spondylolisthesis, and a history of spine surgery were excluded. The Ethics committee of Shahid Beheshti University of Medical Sciences, Tehran, Iran approved the study and, in addition, the patients were asked for their permission to participate in the study by signing a consent form. Validation process included several steps of factor analysis, reliability analysis, construct validation, and discriminative validation. 2.2.2. Factor analysis Factor analysis is applied to predict the dimensions of the items on the questionnaire. In this study, the factor structure of STarT was analyzed using principal component factor analysis with Varimax Rotation. Item loadings on each factor equal to or greater than .4 was considered satisfactory. 2.2.3. Reliability analysis Two common types of reliability are internal consistency and test-retest reliability. The internal consistency of a scale relates to its homogeneity and is assessed with the Cronbach's a that range from 0 to 1. The higher the value, the higher the reliability. Testretest reliability measures stability over time by administering the same test to the same subjects on two occasions. To carry out the test-retest reliability, a total of 35 patients, randomly selected from the primary group, filled out the questionnaire after 24 h. 2.2.4. Construct or convergent validity In order to test the external validity, the correlation between the STarT questionnaire and four validated questionnaires was measured. These four questionnaires are considered as reference standards (Hill et al., 2008). The reference standards were the Roland Morris Disability questionnaire (activity limitation), Coping Strategies questionnaire (catastrophising), Tampa Scale for Kinesiophobia (fear of movement), and Hospital Anxiety and Depression Scale (anxiety and depression). All these questionnaires are available in their Persian versions (Jafari et al., 2010; Montazeri et al., 2003; Mousavi et al., 2006).


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The RMDQ is a 24-item disability questionnaire most commonly used as an outcome measure in patients with LBP (Mousavi et al., 2006). The scoring ranges from 0 to 24 and higher scores mean more disability. The CSQ is a 44-item questionnaire of coping strategies. It has a 6-item subscale for assessment of catastrophizing (Hill et al., 2008). The TSK questionnaire has 17 items. It is used for measuring fear avoidance beliefs. The higher the scores on the questionnaire, the higher fear avoidance of movement (Jafari et al., 2010). The HADS questionnaire has 14 items for assessing depression and anxiety. It has two subscales, one for measuring depression and another for gauging anxiety (Montazeri et al., 2003).

3.1. Factor analysis

2.2.5. Discriminative validity For discriminative validity, Area Under the Curve (AUC) was used. The AUC was calculated for the six items in the STarT-PE according to the reference standards. In this section, the RMDQ was used for items 3 and 4. These items are about disability in daily activity and the RMDQ is a related tool because this questionnaire measures disability, as well. The TSK was used for item 5 because both are about fear avoidance. The HADS was used for items 6 and 8 in order to measure the anxiety and depression, and finally the CSQ was utilized for item 7 for catastrophizing. An AUC of 1.0 is perfect discrimination and an AUC of .5 is discrimination no better than chance.

3.2. Reliability

2.2.6. Statistical analysis All the analyses were performed using SPSS (version 19.0). The clinical characteristics of patients were described by means and standard deviations. The level of significant was set at p < .05. 3. Results A summary of demographic and characteristics of the population is given in Table 1. The duration of the participants' back pain ranged from 3 months to 20 years. Male and female participants were almost of the same proportion. In the STarT subgroups, the number of persons in the low risk group is more than that in the other two groups. Table 1 Clinical characteristics of the study population (n ¼ 295). Variable Gender Male Female Age(year) Pain duration(month) 12 STarT groups(0e9) Low Medium High RMDQ(0e24) TSK(17e68) HADS anxiety(0e21) HADS depression(0e21) CSQ(0e36)

295

295

295 295 295 295 295

Cronbach a ranges from zero to 1 and values .7 indicate adequate internal consistency. The test-retest reliability was assessed using intraclass correlation coefficient that varies from zero to 1 and values above .80 are considered as evidence of excellent reliability (Plichta et al., 2012). Cronbach a was found to be .83 and .81 for STarT and the subscale, respectively. It was significant to observe very little change in Chronbach a by removing each item. The Intraclass Correlation Coefficient value of test-retest was .85. The results showed excellent test-retest reliability for the STarT. 3.3. Construct or convergent validity To test validity, correlations among the Persian versions of RMDQ, TSK, HADS, and CSQ were measured with the pearson correlation coefficient. Correlation values above .40 were considered satisfactory (Hill et al., 2008). Statistical analysis of the correlations between the STarT and the RMDQ, TSK, CSQ, and two subscales of HADS was performed. The correlation between the STarT and the RMD was excellent and the other correlations ranged from good to very good. Each of the STarT items has a score of zero or 1 and higher total scores indicate worse health or more disability. Thus, positive correlations were found between the STarT and RMD, TSK, HADS, and CSQ. Table 3 summarizes the correlations between STarT and the reference standards. 3.4. Discriminative validity

N Mean

SD

Min

Max

149(50.5%) 146(49.5%) 43.03

12.7

20

70

0 120(40.7%) 175(59.3%) 4.12 123(41.7%) 92(31.7%) 80(26.6%) 10.89 43.46 9.01 8.17 14.13

Primarily, to measure sampling adequacy, as the assumption for PCA, Kaiser-Meyer-Olkin was run and revealed an index of .7, that is a sound and acceptable index. Factor analysis with varimax rotation was performed and a 2factor structure extracted with eigenvalues greater than 1 that jointly accounted for 62% of the total variance. The first factor represented psychosocial aspect of STarT (items 5, 6, 7, 8 and 9) that explained 43% of the total variance. The second factor represented biological aspect of STarT (items 1, 2, 3, and 4) accounting for 19% of the total variance. The results of the rotated component matrix are given in Table 2.

AUC was calculated for six items in the STarT that ranged from .734 to .860. The results in Table 4 showed that all these items had proper sensitivities in ROC Curve. 4. Discussion

2.8

0

9

6.6 14.9 6.04 5.8 9.7

0 17 0 0 0

24 68 19 20 36

RMDQ Roland Morris Disability Questionnaire, TSK Tampa Scale of Kinesophobia, HADS Hospital Anxiety and Depression Scale, CSQ Coping Strategy Questionnaire (catastrophisation domain). SD Standard Deviation. Higher scores on STarT indicate worse conditions. Higher scores on RWDQ, TSK, HADS and CSQ indicate worse conditions.

The aim of the present study was to translate the STarT Back Screening Tool (SBT) into Persian and to test the psychometric properties of this new version in NSLBP patients. The STarT was originally in English and it was later translated into other languages such as French, Spanish, and Danish (Bruyere et al., 2012; Gusi et al., 2011; Morso et al., 2011). Currently, there is an Iranian version of this questionnaire provided by another group of researchers who validated it studying with a sample of patients with spinal stenosis (Azimi et al., 2014). The researchers of the present study are the first group who contacted the developers and now our translated version is uploaded in the website of the original questionnaire. (www.keele.ac.uk/startback). Initially, this questionnaire was developed for nonspecific LBP patients and not for those with specific diagnosis (Hill et al., 2008). So, validation of STarT for



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Table 2 Factor Analysis of the Persian e StarT with Very max Rotation. Items

Factor1:Psychosocial

1)My back pain has spread down my legs at some time in the last 2 weeks 2)I have had pain in the shoulder or neck at some time In the last 2 weeks 3)I have only walked short distances because of my back pain 4)In the last two weeks, I have dressed more slowly than usual because of back pain 5)It is not really safe for a person with a condition like mine to be physically active 6)worrying thoughts have been going through my mind a lot of the time 7)I feel that my back pain is terrible and it is never going to get any better 8)In general I have not enjoyed all the things I used to enjoy 9)overall, how bothersome has your back pain been in the last two weeks Item loadings of .4 were shown

Factor2: Biological .806 .855 .780 .708

.563 .900 .684 .890 .615

Table 3 The Pearson correlation coefficient of the STarT with 4 reference standards. STarT STarT

Pearson Correlation Sig. (2-tailed) N Pearson Correlation Sig. (2-tailed) N Pearson Correlation Sig. (2-tailed) N Pearson Correlation Sig. (2-tailed) N Pearson Correlation Sig. (2-tailed) N Pearson Correlation Sig. (2-tailed) N

Anxiety

Depression

RMD

TSK

CSQ

Anxiety

1

.747 .000

295 .747 .000 295

295 1

295

295

295

295

295 .682 .000

295 .708 .000 295

patients with NSLBP was a priority. These two versions have their own differences, as well. Our sample was from NSLBP but in the other version, groups with spinal stenosis were surveyed. Moreover, statistical analyses, i.e. factor analysis and AUC, were analyzed in our investigation but not in other study. Although the STarT questionnaire is a valid, simple, and useful tool for subgrouping low back pain patients, it has its own considerations, as well. For example, targeted treatment based on STarT is not explicit. Medium risk patients refer to physiotherapy, however it is not clear what kind of physiotherapy methods are useful for such patients. It seems that further clinical research are needed to shed light on these uncertainties (Fritz et al., 2011). 4.1. Factor analysis Factor analysis showed that the major loading of STarT-PE was toward psychosocial aspects, which is consistent with the original questionnaire(Hill et al., 2008). To the best of our knowledge, there was not any information about the factor structure of the STarT tool provided in other translations.

295

295

.635 .000 295

.668 .000

.665 .000 295

.683 .000 .683 .000

.665 .000

295

295

295

295

.708 .000

.682 .000 295

295 1

.668 .000

.635 .000

295

.665 .000 .665 .000

CSQ .715 .000

.677 .000 295

295

295 .715 .000

295

295 1

.677 .000

TSK

.811 .000

.867 .000 .867 .000

.811 .000

RMD

.718 .000 295

295 .718 .000

295

Depression

295 1

295 .611 .000

295 .654 .000

295

.654 .000

.611 .000 295

295 1 295

4.2. Reliability The Cronbach a of the Persian STarT was .83 and .81 for the total score and the subscale, respectively. This was similar to the results previously reported by Azimi in the Iranian version (Azimi et al., 2014). The reliability index for the current study is higher than those of Danish and French versions (Morso et al., 2011; Bruyere et al., 2014). ICC was .85, which was lower than that in the French version. Generally, the Persian version of STarT had excellent reliability compared with the original and other versions. 4.3. Discriminative validity The Persian STarT showed significant validity, as compared with the reference questionnaires. The results related to validity were similar to that of the other versions. As shown in Table 3, the highest correlation is between STarT and RMD (.811) and the lowest correlation between STarT and CSQ (.708). As the RMD is a common tool for measuring disability, this excellent correlation shows that STarT can well predict disability in low back pain

Table 4 Area under curve for some items in STarT questionnaire compared with their reference standards. Question on STarT

References

3)I have only walked short distances because of my back pain 4)In the last two weeks,I have dressed more slowly than usual because of back pain 5)It is not really safe for a person with a condition like mine to be physically active 6)worrying thoughts have been going through my mind a lot of the time 7)I feel that my back pain is terrible and it is never going to get any better 8)In general I have not enjoyed all the things I used to enjoy

RMDQ .850(.807e.892) RMDQ .824(.777e.871) TSK .739(.684e.794) Anxiety .791(.741e.842) CSQ .860(.814e.905) Depression .734(.678e.790)


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patients. Also, AUC was used for discriminating validity. To our knowledge, this value was assessed in the original and Danish versions too (Hill et al., 2008; Morso et al., 2011). The Area Under the Curve in Persian version ranged from .73 to .86, which was similar to that of Danish version and a little lower than that in the original version. 4.4. Limitation In the present study, responsiveness of the STarT was not tested. Additional clinical studies are required to confirm this assumption. 5. Conclusion The results of this validation study indicate that the STarT-PE is a valid and reliable instrument for screening in NSLBP patients.

Key points The STarT was translated into Persian and was culturally adapted for Persian-speaking NSLBP patients. Patients who referred to physiotherapy clinics were participants of the study and completed the questionnaire. The STarT has proper internal consistency and reliability and is a valid instrument for assessing and screening NSLBP patients in the Persian-speaking population.

Contribution Mohsen Abedi: Design of the study, Acquisition of data, and preparation of the first draft; Farideh Dehghan Manshadi: Interpretation of data and final approval of the article for submission; Minoo Khalkhali: Interpretation of data, Seyed Javad Mousavi: revision of the Article, Alireza Akbarzadeh Baghban: Analysis of data, Ali Montazeri: Translation and cultural adaptation check of the Questionnaire, Mohamad Parnianpour: Conception and design of the study as well as revision of the article. Acknowledgment The present research was supported by Shahid Beheshti University of Medical Sciences, Tehran, Iran. The authors would like to thank Mrs. Karimi and the honorable staff at Physiotherapy Clinic of Milad Hospital for their great help in data collection.

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