213
Journal of Back and Musculoskeletal Rehabilitation 27 (2014) 213–221 DOI 10.3233/BMR-130439 IOS Press
Validation of the Persian version of the fear avoidance belief questionnaire in patients with low back pain Mohsen Rostamia,b , Negin Nooriana , Mohammad Ali Mansourniac, Elham Sharafia, Amir Eslami Shahr Babakia and Ramin Kordia,b,∗ a
Sports Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran Spine Division, Noorafshar Rehabilitation and Sports Medicine Hospital, Tehran, Iran c Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Science, Tehran, Iran b
Abstract. OBJECTIVES: Fear of pain or re-injury and avoidance attitudes have a great impact on maintenance of chronic low back pain (CLBP) and disability. Fear-Avoidance Beliefs Questionnaire (FABQ) is developed to assess these psychosocial factors. The aim of this study was to provide a translated and validated version of the FABQ for Persian speaking population. METHODS: Forward and backward translation techniques were carried out for translation and cultural adaptation of the questionnaire into Persian. Internal consistency and test-retest reliability were used to assess the reliability of the Persian questionnaire. Construct validity of the scale was assessed by divergent validity (using Spearman correlation coefficient) and exploratory factor analysis. Principle component analysis with varimax rotation method was applied for assessment of factor analysis. RESULTS: The test-retest reliability was excellent with the Intra-class Correlation (ICC) value of 0.802 and 0.808 for the physical activity and work subscales of the questionnaire, respectively. The Chronbach’s alpha coefficient value of 0.89, demonstrated adequate internal consistency of the questionnaire. Factor analysis revealed two factors which could explain 57.9% of the total variance. Items 7, 10 and 11 of the questionnaire were used in both major factors of the final Persian version. Regarding the divergent validity of the questionnaire, data demonstrated no correlation (r < 0.3) between factor 2 (which is about physical activity) and measured clinical variables (pain intensity and level of dysfunction), while factor 1 (which is about work) was fairly correlated with both pain intensity and disability level of the subjects. CONCLUSION: The provided Persian version of FABQ is a reliable and valid measurement and further research into its use as a diagnostic and prognostic tool is warranted. Development of this questionnaire will be useful for comparability between Persian and English language studies and facilitates an international collaboration in this field. Keywords: Low back pain, questionnaire, validation, fear avoidance belief
1. Introduction Low Back Pain (LBP) is a significant health care issue which has a great impact on active population ∗ Corresponding author: Ramin Kordi, Sports Medicine Research Center, Tehran University of Medical Sciences, No 7, Al-e-Ahmad Highway, Tehran, P.O. Box: 14395-578, IR, Iran. Tel.: +98 21 88630227 8; E-mail: [email protected].
and is reported as the most common cause of people missing work [1]. The prevalence of LBP in general population is over 50% and the life time prevalence of at least one episode of pain is estimated about 70% [2]. Due to high prevalence and economic burden of LBP [3], many efforts for treatment of LBP patients have been made. However, there are still many dark points in the etiology, risk factors and therapeutic interventions of LBP. For example, in less than 3%
c 2014 – IOS Press and the authors. All rights reserved ISSN 1053-8127/14/$27.50
214
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
of LBP patients a definite etiology or serious underlying disease can be found [4]. Most of the abnormalities are associated with non-specific LBP which is a benign syndrome ascertained by the exclusion of other spinal disorders [5,6]. The LBP will improve in most of the cases within 12 weeks. However in 5–10% of the cases, the chronic LBP as a multidimensional state will develop [7]. A clinical condition which is highly correlated with great economic load, disability and work loss [3,5]. The mechanisms of chronicity are poorly understood. Despite the abnormality in lumbar muscle activation patterns in patients with CLBP, the isolated biomedical evaluation and pain severity assessments, are not sufficient for a holistic approach to these patients [5,8]. Therefore, parallel to the biomedical factors the researchers have recently put more emphasis on psychosocial factors which also play a pivotal role in the prognosis of patients with CLBP. Several psychosocial models have been developed to explain progression of musculoskeletal pain to chronic pain syndrome. The main concept of all these models which are known as fear-avoidance models is fear of pain or re-injury [8–10]. Reaction to this fear, might comprise two behaviors: confrontation and avoidance. Confrontation with physical activities in non-specific LBP as an adaptive response may reduce fear and lead to recovery. In contrast avoidance of painful experience or activity may contribute to maintenance of CLBP and increase the fear which eventually augments the disability [8]. Reduction in physical activity may lead to decreased muscle flexibility and strength which can exacerbate pain and avoidance vicious cycle [9,11]. On this basis, Waddell et al., developed the Fear Avoidance Beliefs Questionnaire (FABQ), a 16-item self-reporting questionnaire evaluating patients attitude and belief toward the effect of physical activity and work on their LBP [12]. The FABQ is divided into two subscales: FABQ1, which is designed to assess beliefs about work and FABQ2, for assessment of beliefs about physical activity. In addition, this questionnaire is able to predict work loss and impairments in daily living, outcomes of the treatment as well as level of performance in behavioral tests [12–14]. Due to cardinal differences in cultural and psychological characteristics between the countries, there is an increasing need for internationally standardized questionnaires to measure the psychosocial status of patients with LBP in a manner that allows comparison across cultures and countries. The translated and validated version of FABQ is available in French, German, Brazilian, Spanish, Greek, Chinese and Turkish
populations [1,15–20]. To our knowledge psychometric characteristics of FABQ has not been prepared for Persian-speaking patients with LBP. Considering the high prevalence of LBP in different groups of Iranian population [21–23], the purpose of this study was to translate the questionnaire into Persian and assess psychometric properties of the scale.
2. Method 2.1. The scale (Fear-Avoidance Beliefs Questionnaire) The FABQ is used to evaluate patients’ beliefs with regard to the effect of physical activity and work on their LBP. This self reported questionnaire is consisted of 16 items which are divided into two subscales. The first subscale (FABQ1) which evaluates the pain related fear avoidance beliefs about work is scored by items 6, 7, 9, 10, 11, 12, 15 of the questionnaire. The other subscale (FABQ2) assesses the pain related fear avoidance beliefs of LBP patients about physical activity and is issued by items 2 through 5. The five remaining items are ineffective and delusive and will not be included in final scoring of the patients. The agreement of patients with each item will be scored by a 7-point Likert scale, ranging from 0 (completely disagree) to 6 (completely agree). Higher FABQ scores indicate higher fear avoidance beliefs. The score for each subscale is counted and used independently [12]. 2.2. Instruments for evaluation In all participants, evaluation at the baseline and after two weeks was performed using the following tools: 1) VAS was used for assessment of pain intensity indirectly. This tool is a 100 mm continuous horizontal line which indicates the level of pain ranging between two end points [24]. 2) The validated Persian version of Roland Morris Disability Questionnaire (RMDQ) [25], was used to infer the level of LBP induced disability in the patients. 3) The fear avoidance beliefs of the patients were evaluated by the provided FABQ. 2.3. Translation and cultural adaptation of the scale Forward and backward translation was carried out to translate the original English version of fear-avoidance-beliefs questionnaire (FABQ) into Persian. Two independent translators with no medical knowledge, who
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
their mother tongue was Persian and were not familiar with the questionnaire and the purpose of study, translated the scale into Persian separately. The translations were instructed to be conceptual rather than word-for-word translation. The two translations were then reviewed for any discrepancies. After reaching a consensus, a single Persian translation was produced. Then, two professional translators who their mother tongue was English, back translated the Persian version of the questionnaire into English. This process was performed to assure that the items contents of the original version were preserved in the translated version. Finally, the group of translators, the investigators of this study, a methodologist and five specialists in rheumatology, orthopedic surgery, physiotherapy, physical medicine and rehabilitation and sport medicine as the expert committee reviewed all forward and backward translations as well as cultural adaptation process. The aim of this process was to consolidate all the versions and provide a pre-final version of the scale (the Persian FABQ).
215
40 patients who were randomly selected from the total study population. Patients were visited at the baseline and after two weeks and at both visits the VAS scale, previously validated Persian version of Roland Morris disability Questionnaire (RMDQ) as well as the prefinal version of Persian FABQ were provided to them separately. The patients were interviewed individually by one of the authors and the concept which the patients perceived with regard to each item of the FABQ as well as the need for any changes in the items was asked. The scale was re-evaluated by the authors based on suggestions and comments of the patients. Consequently, the final Persian version of FABQ was prepared for further testing. 2.5. Testing the questionnaire Finally, 136 recruited patients were evaluated using the Persian version of FABQ, VAS scale as well as validated Persian version of RMDQ. The collected data were used for statistical analysis to test the validation of the provided Persian version of the FABQ.
2.4. Study population 2.6. Statistical analysis The participants of this study were recruited from patients who were known case of CLBP (more than 12 weeks history of LBP over the past year) who referred to spine clinics of two hospitals which are affiliated with the Tehran University of Medical Sciences. Inclusion criteria were current episode of LBP during the past month, ability to read and understand the Persian language and having active occupational status. Exclusion criteria were pregnancy, unemployment, serious medical disease including: infection, tumor, inflammatory and cardiovascular disease, severe spinal disorders (direct trauma to the spine, vertebral fracture, stenosis), musculoskeletal disorders or injuries, Central Nervous System disturbance, severe neurologic disorders, history of previous back surgery during the last year and psychiatric problems. According to these criteria 150 eligible patients were recruited in the study between March 2010–February 2011. At the baseline a comprehensive evaluation composed of history taking and physical examination was carried out in all participants and the demographic information as well as clinical data were obtained. All the patients were separately interviewed by one of the researchers and the informed consent which was approved by the Ethics Committee of our institution was obtained. Face validity as well as Test-retest reliability were performed in a pilot group. This group was consisted of
2.6.1. Reliability To measure the questionnaire homogeneity and reproducibility the internal consistency and the testretest reliability of the questionnaire were measured respectively. Internal consistency was assessed with the Cronbach’s alpha coefficient. Test–retest reliability was measured using Intra-class Correlation Coefficient (ICC, one-way random-effects model). In this regard, the minimum adequate value for Cronbach’s alpha was considered as 0.70 [26] while for ICC, values more than 0.8 were considered as excellent [27]. 2.6.2. Construct validity In this study construct validity of the questionnaire was assessed by factor analysis and divergent validity. Exploratory factor analysis was used to examine the underlying association between the 16 items of the questionnaire. Initial factors were extracted using principal components analysis and then rotated using the varimax rotation method. A factor loading of more than 0.5 was considered as high. Also, to measure the divergent validity of the questionnaire, we aimed to show that the concept which is measured by FABQ is different from those which can be measured by RMDQ and VAS. In this regard, using the spearman’s correlation coefficient, the correlation between the FABQ
216
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire Table 1 Demographic and clinical characteristics of patients participated in the study Variables Age (year) Pain duration (Months) Pain intensity (VAS) Disability (RMDQ) FABQ-Physical activity FABQ-work
Mean 48.70 5.16 51.45 11.03 21.35 28.80
Range 23–76 1–17 0–100 0–24 0–30 0–66
Standard deviation (SD) 13.13 3.41 26.29 6.66 6.88 16.72
VAS: Visual Analogue Scale; RMDQ: Roland Morris Disability Questionnaire; FABQ: Fear Avoidance Belief Questionnaire. Table 2 Intraclass Correlation Coefficient for each item and related subscales at 15 days intervals Subscales Physical activity
Work
Items 1 2 3 4 5
ICC (r) 0.844 0.787 0.746 0.767 0.755
95% CI 0.722 to 0.916 0.628 to 0.883 0.564 to 0.859 0.598 to 0.872 0.579 to 0.864
ICC Values for subscales (95% CI) 0.802 (0.652 to 0.891)
6 7 9 10 11 12 13 14 15 16
0.848 0.772 0.855 0.747 0.733 0.649 0.725 0.605 0.685 0.613
0.728 to 0.918 0.606 to 0.875 0.738 to 0.922 0.566 to 0.859 0.545 to 0.852 0.422 to 0.800 0.530 to 0.848 0.352 to 0.776 0.466 to 0.826 0.366 to 0.779
0.808 (0.645 to 0.901)
Total (FABQ)
0.805 (0.640 to 0.900)
ICC: Intra-Class Correlation Coefficient; CI: Confidence Interval.
total and subscale scores and the results of the subjects from RMDQ and VAS were calculated. The values of the test were categorized as excellent correlation (> 0.91), good (0.90–0.71), moderate (0.70–0.51), fair (0.50–0.31) and no correlation (< 0.30) [28]. 3. Result 3.1. Demographic findings Of all 150 LBP patients which were eligible for recruitment in the study, 14 patients were excluded from analysis due to personal issues (n = 8) and meeting one of the exclusion criteria (n = 6). Data of the remained 136 patients were considered in the final analysis. Demographic characteristics of the patients and the data resulted from RMDQ and FABQ as well as VAS scale, are provided in Table 1. 3.2. Testing the scale 3.2.1. Translation and adaptation Evaluating the results obtained from 136 patients, it was found that no cultural adaptation is needed
for the most of questionnaire items except some minor changes in the word choice of the sentences (Appendix). However, data obtained with regard to the item 8 of the questionnaire showed extensive skewness and approximately 82% of the answers were related to “0” or “Completely disagree”. Furthermore, while there is no compensation for LBP in most of the work places in Iran, item 8 was irrelevant and inappropriate for the Persian version and was removed from analysis. 3.2.2. Reliability The Chronbach’s alpha coefficient for the questionnaire was calculated as 0.89 with α = 0.80 for FABQphysical and α = 0.89 for FABQ-Work. The mentioned values demonstrated adequate internal consistency of the questionnaire. The Test-Retest Reliability was tested on 40 patients. As it is shown in Table 2, the Intraclass Correlation Coefficient (ICC) for physical activity and work subscales were 0.802 and 0.808 respectively. Furthermore the Coefficient of r = 0.805 was estimated for the total questionnaire as an indicator of excellent reliability of the Persian FABQ.
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
217
Table 3 Principal factor analysis of the questionnaires’ items, using Varimax rotation method Principle factors Factor 1 (Variance explained: 45.72%, Eigenvalue: 6.86)
Items 7 9 10 11 12 13 14 15 16
Loading∗ 0.507 0.682 0.629 0.637 0.796 0.772 0.783 0.595 0.678
Mean (SD) 3.72 (1.92) 2.34 (2.05) 3.54 (1.92) 3.40 (1.92) 2.88 (2.19) 2.94 (2.27) 2.73 (2.31) 1.71 (3.49) 0.97 (1.61)
Factor 2 (Variance explained: 12.19%, Eigenvalue: 1.83)
1 2 3 4 5 6 7 10 11
0.707 0.763 0.756 0.735 0.537 0.558 0.599 0.502 0.571
3.93 (1.97) 4.36 (1.80) 4.14 (1.83) 4.73 (1.69) 4.08 (1.87) 3.39 (2.12) 3.72 (1.92) 3.54 (1.92) 3.40 (1.92)
∗ The
items related to each factor were confirmed to be stable if they were loaded above 0.5.
Table 4 Spearman’s rank correlation coefficient of subscales of the FABQ to pain and disability Variable Pain intensity (VAS) LBP induced disability (RMDQ) ∗ Presented
Physical activity∗ 0.260 0.292
Work∗ 0.494 0.418
FABQ (Total)∗ 0.483 0.435
“rho” correlation values are significant at the level of 0.01.
3.2.3. Construct validity Exploratory Factor Analysis (EFA) was carried out on results obtained from 136 patients in order to explore the factor structure of the scale. The analysis determined two factor structures which could explain 57.9% of the total variance (Table 3). These two factors were confirmed using scree-plot method. Comparable to the original version, factor 1 was focused mainly on the fear avoidance beliefs about work. Items 7 through 16 (except item 8 which was excluded) were loaded above 0.5 on this factor with 45.72% of the total variance. Factor 2 which was able to show the relation between fear avoidance beliefs with regard to patients’ physical activity, accounted for 12.19% of the explained total variance. In this factor, items 1 through 6 and 7, 10 and 11 were loaded above 0.5. In this regard, we found that item 6 of the provided Persian FABQ was more compatible with the second factor unlike the original version [12]. Data of the present study also showed that items 7, 10 and 11 which represent the beliefs of the patients about works’ effect on aggregation of the pain, were strongly associated with both factors however their value of loading was higher on the first factor, compared with the second one (Table 3). This result, could explain their higher associa-
tions with the items related to the work subscale. The results of inter-item correlation showed that items 10 and 11 as well as 12 and 13 were strongly correlated (with r = 0.85 and 0.88 respectively). Although, this level of correlation was close to redundancy value [29], these items were preserved unchanged in the analysis. Correlation of the FABQs’ subscales with other clinical variables was carried out to investigate the divergent construct validity of the survey. The FABQ2 (Fear and Avoidance Beliefs about physical activity) showed little or no relationship with VAS (ρ = 0.26, P < 0.001) and RMDQ for measuring disability related to LBP (ρ = 0.29, P < 0.001). The FABQ1 (Fear and Avoidance Beliefs about work) as well as the total questionnaire demonstrated fair relationship to both VAS and RMDQ (Table 4). These findings suggest an acceptable divergent validity of the provided questionnaire.
4. Discussion Fear of pain which leads to avoidance behaviors is much more debilitating than pain severity [14]. Recognition of these behavioral and psychosocial factors
218
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
which are suggested as the main predictors of chronicity, might be helpful to more effectively treat LBP patients and decrease the enormous burden of the disease [12,19,30]. Lack of a standard tool for measurement of these factors could be considered as a major obstacle in the management of LBP patient. While FABQ is known as a reliable and valid tool for evaluation of behavioral and psychosocial affects of LBP on work and physical activity of patients, to our knowledge no validated Persian version of the questionnaire has been still developed. In this study forward and backward translation was performed to translate the original questionnaire into Persian. Conceptual instead of word-for-word translation was aimed to store the meaning of each item and the perception of the whole questionnaire. Although such adaptations may lead to decline disagreements as well as missing data [16], our findings showed that the validated Persian version of FABQ has appropriate psychometric properties. Therefore it is easy to use for assessing fear of pain and avoidance behaviors of Iranian LBP patients as a part of complete evaluation of patients prior to the treatment. In addition, using this standard and validated questionnaire, comparison of the results obtained from Iranian population with international studies as well as meta analysis will be possible [18,31]. 4.1. Reliability In this investigation, the Persian FABQ provided the same values when it was applied repeatedly to the same patient. The test-retest reliability was excellent with an ICC of 0.802 and 0.808 for the items related to physical activity and work domains, respectively. The coefficient of 0.805 was estimated for all items of the questionnaire together. The ICC was comparable to the original study by Waddell et al., (0.74) [12] and other validated versions in French, (ICC: 0.72 for physical activity related subscale and ICC: 0.88 for work related subscale) [18], German (0.87) [19], Spanish (0.96) [1] and Greek (0.86) [20]. The interval between two records of the patients in this study was 15 days. Pfingsten et al. [19] and Kovacs et al. [1], could observe similar satisfactory reliability in their studies which were repeated after 29 days and 14 days of the baseline respectively. According to the current study, the Cronbach’s alpha coefficient of the total questionnaire was 0.89, which demonstrated a high homogeneity of the Persian-FABQ. This result is in consistency with the internal validity of the original (0.82) [12] German (0.91) [19] and Turkish (0.91) [16] versions of the questionnaire.
4.2. Construct validity Construct validity as one of the most important features of a scale, can explain the construct of the developed measure and estimate the correlations. The construct of a scale can be assessed using convergent and divergent validity as well as factor analysis [32]. Due to lack of any previous validated instrument for measurement of fear avoidance beliefs in Iranian population, the convergent validity was not performed in this study. However, divergent validity of the questionnaire was tested to show that the concept concerned in FABQ measure was rather different from what was measured by VAS and RMDQ. In this regard, no correlation between the pain intensity (measured by VAS) and disability (measured by RMDQ) of the LBP patients and their fear avoidance beliefs about physical activity was found. However we found that both the pain intensity and disability of the subjects have fair correlation with the fear avoidance beliefs of the subjects about work. This was in contrast with the results of the original version [12], as well as validated Turkish [16] and French [18] versions of the scale which reported no correlation between two subscales of the questionnaire and pain intensity of subjects. Cultural differences as well as financial support of governmental companies for work absence of employees in Iran, might be the possible explanations of this difference between our results and previous studies. In accordance with the findings of the present study, Waddell et al. [12] reported a significant correlation between the fear avoidance beliefs about work and self-reported disability in performing daily-living activities among LBP patients. It is well documented that pain-related fear might influence the cognition of the patients and lead to hypervigilance of the patients from the possible threats. This fear contributes to augmented psychophysiological awareness to confront with threatening situations [11]. Work related injuries as a threat, might have a profound impact on beliefs and avoidance behaviors of LBP patients about work. In addition, this effect as one of the main predictors of physical performance, may lead to work loss and disability as well as greater perception of pain [11,12]. In this study, to extract the major factors of the questionnaire, the exploratory factor analysis was performed [12,18,19]. The two-factor structure which was extracted from factor analysis of the Persian FABQ, was similar to the original version [12] and studies of Korkmaz et al. [16] and Staerkle et al. [33]. It was rather different from three-factor structure which
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
was reported in validated German and Greek versions. In these two versions, the work subscale known as FABQ1 in our study, was furthermore subdivided into two sections, determined as “Work as a cause” and “Work prognosis” [19,20]. The two-factor structure which was extracted from the provided Persian questionnaire could account for 57.9% of the total variance which was close to the variance explained by Waddell et al. [12] (60.2%). Unlike the original version in which item 1 was excluded due to inconsistent loading, this item had appropriate factor loading in our study and was preserved. Furthermore, items 13, 14 and 16, which were highly correlated items in the original version, had not shown high correlation in the current study and were not excluded [12]. In this investigation, primary approaches in assessment of psychometric properties of the Persian FABQ were performed. There are some points, which are desirable to be evaluated in future surveys. According to the inclusion criteria of the study, the patients with active working status were recruited. This may lead to decline the possibility to generalize the outcomes of the study to some retired, unemployed and house wife patients. As another limitation of the study, we only tested the divergent validity of the Persian FABQ with the pain intensity and disability of the patients. Investigating the correlation between Persian FABQ and other variables including education, occupational status, psychological distress, depression and anxiety should be considered in future studies.
5. Conclusion This study demonstrated that Persian FABQ has adequate reliability and validity. Furthermore, using this questionnaire for assessment of fear avoidance beliefs in Persian LBP patients, as a part of complete evaluation, is really worth considering. Development of this questionnaire will be useful for comparability between Persian and English language studies and facilitates an international collaboration in this field. In addition, development of the Persian version of FABQ will be beneficial for clinical assessment of the subjects with LBP. It is reported by Swinkels-Meewisse et al. [34] that targeting the pain related fear of the subjects with acute stages of LBP is an effective way of preventing the transition of the disease from acute to chronic. Therefore, this questionnaire can help the clinicians to recognize the patients who need psychological interventions for reduction of pain related fear which leads to reduction of the disability of the patients.
219
Ethical approval Before the study, the process and aim of the study were described to the patients. All of the finally enrolled patients signed a written informed consent. Approval of this study was obtained from the Ethical Committee of Tehran University of Medical Sciences.
Funding This study was funded by Tehran University of Medical Sciences.
Conflict of interest There is no conflict of interest.
References [1]
Kovacs, F.M., et al., Psychometric characteristics of the Spanish version of the FAB Questionnaire. Spine, 2006. 31(1): p. 104. [2] Hammill, R.R., J.R. Beazell, and J.M. Hart, Neuromuscular consequences of low back pain and core dysfunction. Clinics in Sports Medicine, 2008. 27(3): p. 449-462. [3] Frymoyer, J. and W. Cats-Baril, An overview of the incidences and costs of low back pain. The Orthopedic Clinics of North America, 1991. 22(2): p. 263. [4] Coste, J., et al., Clinical and psychological diversity of nonspecific low-back pain. A new approach towards the classification of clinical subgroups. Journal of Clinical Epidemiology, 1991. 44(11): p. 1233-1245. [5] Dubois, J.D., et al., Effect of experimental low back pain on neuromuscular control of the trunk in healthy volunteers and patients with chronic low back pain. Journal of electromyography and kinesiology: Official journal of the International Society of Electrophysiological Kinesiology, 2011. [6] Kordi, R. and M. Rostami, Low Back Pain in Children and Adolescents: an Algorithmic Clinical Approach. Iran J Pediatr, 2011. 21(3): p. 259-270. [7] Manchikanti, L., Epidemiology of low back pain. Pain Physician, 2000. 3(2): p. 167-192. [8] Vlaeyen, J.W.S., et al., Fear of movement/(re) injury and muscular reactivity in chronic low back pain patients: an experimental investigation. Pain, 1999. 82(3): p. 297-304. [9] Lethem, J., et al., Outline of a Fear-Avoidance Model of exaggerated pain perception – I. Behaviour Research and Therapy, 1983. 21(4): p. 401-408. [10] Vlaeyen, J.W., et al., Fear of movement/(re)injury in chronic low back pain and its relation to behavioral performance. Pain, 1995. 62(3): p. 363-72. [11] Vlaeyen, J.W.S. and S.J. Linton, Fear-avoidance and its consequences in chronic musculoskeletal pain: a state of the art. Pain, 2000. 85(3): p. 317-332. [12] Waddell, G., et al., A Fear-Avoidance Beliefs Questionnaire (FABQ) and the role of fear-avoidance beliefs in chronic low back pain and disability. Pain, 1993. 52(2): p. 157-168.
220 [13]
[14]
[15]
[16]
[17]
[18] [19]
[20]
[21]
[22]
[23]
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire Klenerman, L., et al., The prediction of chronicity in patients with an acute attack of low back pain in a general practice setting. Spine, 1995. 20(4): p. 478. Crombez, G., et al., Pain-related fear is more disabling than pain itself: evidence on the role of pain-related fear in chronic back pain disability. Pain, 1999. 80(1-2): p. 329-339. de Abreu, A.M., et al., Versão brasileira do Fear Avoidance Beliefs Questionnaire The Brazilian version of the Fear Avoidance Beliefs Questionnaire. Cad. Saúde Pública, 2008. 24(3): p. 615-623. Korkmaz, N., et al., Validation and reliability of the Turkish version of the fear avoidance beliefs questionnaire in patients with low back pain. European Journal of Physical and Rehabilitation Medicine, 2009. 45(4): p. 527. Pei, L., J. Xia, and J. Yan, Cross-cultural Adaptation, Reliability and Validity of the Chinese Version of the Fear Avoidance Beliefs Questionnaire. The Journal of International Medical Research, 2010. 38(6): p. 1985-1996. Chaory, K., et al., Validation of the French version of the fear avoidance belief questionnaire. Spine, 2004. 29(8): p. 908. Pfingsten, M., et al., Validation of the German version of the fear-avoidance beliefs questionnaire (FABQ). European Journal of Pain, 2000. 4(3): p. 259-266. Georgoudis, G., et al., Cognitive assessment of musculoskeletal pain with a newly validated Greek version of the FearAvoidance Beliefs Questionnaire (FABQ). European Journal of Pain, 2007. 11(3): p. 341-351. Mohseni-Bandpei, M.A., et al., Occupational back pain in Iranian nurses: An epidemiological study. Br J Nurs, 2006. 15(17): p. 914-7. Mohseni-Bandpei, M.A., et al., Prevalence and risk factors associated with low back pain in Iranian surgeons. J Manipulative Physiol Ther, 2011. 34(6): p. 362-70. Mousavi, S.J., et al., Low back pain in Iran: A growing need to adapt and implement evidence-based practice in developing countries. Spine (Phila Pa 1976), 2011. 36(10): p. E638-46.
[24]
Wewers, M.E. and N.K. Lowe, A critical review of visual analogue scales in the measurement of clinical phenomena. Research in Nursing & Health, 1990. 13(4): p. 227-236. [25] DeOreo, P.B., Hemodialysis patient-assessed functional health status predicts continued survival, hospitalization, and dialysis-attendance compliance* 1. American Journal of Kidney Diseases, 1997. 30(2): p. 204-212. [26] George, D. and P. Mallery, SPSS for Windows Step-by-Step: A Simple Guide and Reference, 14.0 update (7th Edition). 2006: Allyn & Bacon. [27] Fleiss, J., B. Levin, and M. Paik, Statistical Methods for Rates and Proportions, 3rd Edition. 2003: Wiley. [28] Atkinson, G. and A. Nevill, Comment on the use of concordance correlation to assess the agreement between two variables. 1997, JSTOR. p. 775-777. [29] Tabachnick, B. and L. Fidhi, l 1996. Using multivariate statistics 3rd ed, Harper Collins, New York. [30] Feuerstein, M. and P. Beattie, Biobehavioral factors affecting pain and disability in low back pain: mechanisms and assessment. Physical Therapy, 1995. 75(4): p. 267-280. [31] Guillemin, F., C. Bombardier, and D. Beaton, Cross-cultural adaptation of health-related quality of life measures: literature review and proposed guidelines. Journal of Clinical Epidemiology, 1993. 46(12): p. 1417-1432. [32] Fayers, P.M. and D. Machin, Quality of life: the assessment, analysis and interpretation of patient-reported outcomes. 2007: Wiley. [33] Staerkle, R., et al., Longitudinal validation of the fearavoidance beliefs questionnaire (FABQ) in a Swiss-German sample of low back pain patients. European Spine Journal, 2004. 13(4): p. 332-340. [34] Swinkels-Meewisse, I.E., et al., Fear of movement/(re)injury predicting chronic disabling low back pain: a prospective inception cohort study. Spine (Phila Pa 1976), 2006. 31(6): p. 658-64.
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
Appendix
221
Journal of Back and Musculoskeletal Rehabilitation 27 (2014) 213–221 DOI 10.3233/BMR-130439 IOS Press
Validation of the Persian version of the fear avoidance belief questionnaire in patients with low back pain Mohsen Rostamia,b , Negin Nooriana , Mohammad Ali Mansourniac, Elham Sharafia, Amir Eslami Shahr Babakia and Ramin Kordia,b,∗ a
Sports Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran Spine Division, Noorafshar Rehabilitation and Sports Medicine Hospital, Tehran, Iran c Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Science, Tehran, Iran b
Abstract. OBJECTIVES: Fear of pain or re-injury and avoidance attitudes have a great impact on maintenance of chronic low back pain (CLBP) and disability. Fear-Avoidance Beliefs Questionnaire (FABQ) is developed to assess these psychosocial factors. The aim of this study was to provide a translated and validated version of the FABQ for Persian speaking population. METHODS: Forward and backward translation techniques were carried out for translation and cultural adaptation of the questionnaire into Persian. Internal consistency and test-retest reliability were used to assess the reliability of the Persian questionnaire. Construct validity of the scale was assessed by divergent validity (using Spearman correlation coefficient) and exploratory factor analysis. Principle component analysis with varimax rotation method was applied for assessment of factor analysis. RESULTS: The test-retest reliability was excellent with the Intra-class Correlation (ICC) value of 0.802 and 0.808 for the physical activity and work subscales of the questionnaire, respectively. The Chronbach’s alpha coefficient value of 0.89, demonstrated adequate internal consistency of the questionnaire. Factor analysis revealed two factors which could explain 57.9% of the total variance. Items 7, 10 and 11 of the questionnaire were used in both major factors of the final Persian version. Regarding the divergent validity of the questionnaire, data demonstrated no correlation (r < 0.3) between factor 2 (which is about physical activity) and measured clinical variables (pain intensity and level of dysfunction), while factor 1 (which is about work) was fairly correlated with both pain intensity and disability level of the subjects. CONCLUSION: The provided Persian version of FABQ is a reliable and valid measurement and further research into its use as a diagnostic and prognostic tool is warranted. Development of this questionnaire will be useful for comparability between Persian and English language studies and facilitates an international collaboration in this field. Keywords: Low back pain, questionnaire, validation, fear avoidance belief
1. Introduction Low Back Pain (LBP) is a significant health care issue which has a great impact on active population ∗ Corresponding author: Ramin Kordi, Sports Medicine Research Center, Tehran University of Medical Sciences, No 7, Al-e-Ahmad Highway, Tehran, P.O. Box: 14395-578, IR, Iran. Tel.: +98 21 88630227 8; E-mail: [email protected].
and is reported as the most common cause of people missing work [1]. The prevalence of LBP in general population is over 50% and the life time prevalence of at least one episode of pain is estimated about 70% [2]. Due to high prevalence and economic burden of LBP [3], many efforts for treatment of LBP patients have been made. However, there are still many dark points in the etiology, risk factors and therapeutic interventions of LBP. For example, in less than 3%
c 2014 – IOS Press and the authors. All rights reserved ISSN 1053-8127/14/$27.50
214
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
of LBP patients a definite etiology or serious underlying disease can be found [4]. Most of the abnormalities are associated with non-specific LBP which is a benign syndrome ascertained by the exclusion of other spinal disorders [5,6]. The LBP will improve in most of the cases within 12 weeks. However in 5–10% of the cases, the chronic LBP as a multidimensional state will develop [7]. A clinical condition which is highly correlated with great economic load, disability and work loss [3,5]. The mechanisms of chronicity are poorly understood. Despite the abnormality in lumbar muscle activation patterns in patients with CLBP, the isolated biomedical evaluation and pain severity assessments, are not sufficient for a holistic approach to these patients [5,8]. Therefore, parallel to the biomedical factors the researchers have recently put more emphasis on psychosocial factors which also play a pivotal role in the prognosis of patients with CLBP. Several psychosocial models have been developed to explain progression of musculoskeletal pain to chronic pain syndrome. The main concept of all these models which are known as fear-avoidance models is fear of pain or re-injury [8–10]. Reaction to this fear, might comprise two behaviors: confrontation and avoidance. Confrontation with physical activities in non-specific LBP as an adaptive response may reduce fear and lead to recovery. In contrast avoidance of painful experience or activity may contribute to maintenance of CLBP and increase the fear which eventually augments the disability [8]. Reduction in physical activity may lead to decreased muscle flexibility and strength which can exacerbate pain and avoidance vicious cycle [9,11]. On this basis, Waddell et al., developed the Fear Avoidance Beliefs Questionnaire (FABQ), a 16-item self-reporting questionnaire evaluating patients attitude and belief toward the effect of physical activity and work on their LBP [12]. The FABQ is divided into two subscales: FABQ1, which is designed to assess beliefs about work and FABQ2, for assessment of beliefs about physical activity. In addition, this questionnaire is able to predict work loss and impairments in daily living, outcomes of the treatment as well as level of performance in behavioral tests [12–14]. Due to cardinal differences in cultural and psychological characteristics between the countries, there is an increasing need for internationally standardized questionnaires to measure the psychosocial status of patients with LBP in a manner that allows comparison across cultures and countries. The translated and validated version of FABQ is available in French, German, Brazilian, Spanish, Greek, Chinese and Turkish
populations [1,15–20]. To our knowledge psychometric characteristics of FABQ has not been prepared for Persian-speaking patients with LBP. Considering the high prevalence of LBP in different groups of Iranian population [21–23], the purpose of this study was to translate the questionnaire into Persian and assess psychometric properties of the scale.
2. Method 2.1. The scale (Fear-Avoidance Beliefs Questionnaire) The FABQ is used to evaluate patients’ beliefs with regard to the effect of physical activity and work on their LBP. This self reported questionnaire is consisted of 16 items which are divided into two subscales. The first subscale (FABQ1) which evaluates the pain related fear avoidance beliefs about work is scored by items 6, 7, 9, 10, 11, 12, 15 of the questionnaire. The other subscale (FABQ2) assesses the pain related fear avoidance beliefs of LBP patients about physical activity and is issued by items 2 through 5. The five remaining items are ineffective and delusive and will not be included in final scoring of the patients. The agreement of patients with each item will be scored by a 7-point Likert scale, ranging from 0 (completely disagree) to 6 (completely agree). Higher FABQ scores indicate higher fear avoidance beliefs. The score for each subscale is counted and used independently [12]. 2.2. Instruments for evaluation In all participants, evaluation at the baseline and after two weeks was performed using the following tools: 1) VAS was used for assessment of pain intensity indirectly. This tool is a 100 mm continuous horizontal line which indicates the level of pain ranging between two end points [24]. 2) The validated Persian version of Roland Morris Disability Questionnaire (RMDQ) [25], was used to infer the level of LBP induced disability in the patients. 3) The fear avoidance beliefs of the patients were evaluated by the provided FABQ. 2.3. Translation and cultural adaptation of the scale Forward and backward translation was carried out to translate the original English version of fear-avoidance-beliefs questionnaire (FABQ) into Persian. Two independent translators with no medical knowledge, who
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
their mother tongue was Persian and were not familiar with the questionnaire and the purpose of study, translated the scale into Persian separately. The translations were instructed to be conceptual rather than word-for-word translation. The two translations were then reviewed for any discrepancies. After reaching a consensus, a single Persian translation was produced. Then, two professional translators who their mother tongue was English, back translated the Persian version of the questionnaire into English. This process was performed to assure that the items contents of the original version were preserved in the translated version. Finally, the group of translators, the investigators of this study, a methodologist and five specialists in rheumatology, orthopedic surgery, physiotherapy, physical medicine and rehabilitation and sport medicine as the expert committee reviewed all forward and backward translations as well as cultural adaptation process. The aim of this process was to consolidate all the versions and provide a pre-final version of the scale (the Persian FABQ).
215
40 patients who were randomly selected from the total study population. Patients were visited at the baseline and after two weeks and at both visits the VAS scale, previously validated Persian version of Roland Morris disability Questionnaire (RMDQ) as well as the prefinal version of Persian FABQ were provided to them separately. The patients were interviewed individually by one of the authors and the concept which the patients perceived with regard to each item of the FABQ as well as the need for any changes in the items was asked. The scale was re-evaluated by the authors based on suggestions and comments of the patients. Consequently, the final Persian version of FABQ was prepared for further testing. 2.5. Testing the questionnaire Finally, 136 recruited patients were evaluated using the Persian version of FABQ, VAS scale as well as validated Persian version of RMDQ. The collected data were used for statistical analysis to test the validation of the provided Persian version of the FABQ.
2.4. Study population 2.6. Statistical analysis The participants of this study were recruited from patients who were known case of CLBP (more than 12 weeks history of LBP over the past year) who referred to spine clinics of two hospitals which are affiliated with the Tehran University of Medical Sciences. Inclusion criteria were current episode of LBP during the past month, ability to read and understand the Persian language and having active occupational status. Exclusion criteria were pregnancy, unemployment, serious medical disease including: infection, tumor, inflammatory and cardiovascular disease, severe spinal disorders (direct trauma to the spine, vertebral fracture, stenosis), musculoskeletal disorders or injuries, Central Nervous System disturbance, severe neurologic disorders, history of previous back surgery during the last year and psychiatric problems. According to these criteria 150 eligible patients were recruited in the study between March 2010–February 2011. At the baseline a comprehensive evaluation composed of history taking and physical examination was carried out in all participants and the demographic information as well as clinical data were obtained. All the patients were separately interviewed by one of the researchers and the informed consent which was approved by the Ethics Committee of our institution was obtained. Face validity as well as Test-retest reliability were performed in a pilot group. This group was consisted of
2.6.1. Reliability To measure the questionnaire homogeneity and reproducibility the internal consistency and the testretest reliability of the questionnaire were measured respectively. Internal consistency was assessed with the Cronbach’s alpha coefficient. Test–retest reliability was measured using Intra-class Correlation Coefficient (ICC, one-way random-effects model). In this regard, the minimum adequate value for Cronbach’s alpha was considered as 0.70 [26] while for ICC, values more than 0.8 were considered as excellent [27]. 2.6.2. Construct validity In this study construct validity of the questionnaire was assessed by factor analysis and divergent validity. Exploratory factor analysis was used to examine the underlying association between the 16 items of the questionnaire. Initial factors were extracted using principal components analysis and then rotated using the varimax rotation method. A factor loading of more than 0.5 was considered as high. Also, to measure the divergent validity of the questionnaire, we aimed to show that the concept which is measured by FABQ is different from those which can be measured by RMDQ and VAS. In this regard, using the spearman’s correlation coefficient, the correlation between the FABQ
216
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire Table 1 Demographic and clinical characteristics of patients participated in the study Variables Age (year) Pain duration (Months) Pain intensity (VAS) Disability (RMDQ) FABQ-Physical activity FABQ-work
Mean 48.70 5.16 51.45 11.03 21.35 28.80
Range 23–76 1–17 0–100 0–24 0–30 0–66
Standard deviation (SD) 13.13 3.41 26.29 6.66 6.88 16.72
VAS: Visual Analogue Scale; RMDQ: Roland Morris Disability Questionnaire; FABQ: Fear Avoidance Belief Questionnaire. Table 2 Intraclass Correlation Coefficient for each item and related subscales at 15 days intervals Subscales Physical activity
Work
Items 1 2 3 4 5
ICC (r) 0.844 0.787 0.746 0.767 0.755
95% CI 0.722 to 0.916 0.628 to 0.883 0.564 to 0.859 0.598 to 0.872 0.579 to 0.864
ICC Values for subscales (95% CI) 0.802 (0.652 to 0.891)
6 7 9 10 11 12 13 14 15 16
0.848 0.772 0.855 0.747 0.733 0.649 0.725 0.605 0.685 0.613
0.728 to 0.918 0.606 to 0.875 0.738 to 0.922 0.566 to 0.859 0.545 to 0.852 0.422 to 0.800 0.530 to 0.848 0.352 to 0.776 0.466 to 0.826 0.366 to 0.779
0.808 (0.645 to 0.901)
Total (FABQ)
0.805 (0.640 to 0.900)
ICC: Intra-Class Correlation Coefficient; CI: Confidence Interval.
total and subscale scores and the results of the subjects from RMDQ and VAS were calculated. The values of the test were categorized as excellent correlation (> 0.91), good (0.90–0.71), moderate (0.70–0.51), fair (0.50–0.31) and no correlation (< 0.30) [28]. 3. Result 3.1. Demographic findings Of all 150 LBP patients which were eligible for recruitment in the study, 14 patients were excluded from analysis due to personal issues (n = 8) and meeting one of the exclusion criteria (n = 6). Data of the remained 136 patients were considered in the final analysis. Demographic characteristics of the patients and the data resulted from RMDQ and FABQ as well as VAS scale, are provided in Table 1. 3.2. Testing the scale 3.2.1. Translation and adaptation Evaluating the results obtained from 136 patients, it was found that no cultural adaptation is needed
for the most of questionnaire items except some minor changes in the word choice of the sentences (Appendix). However, data obtained with regard to the item 8 of the questionnaire showed extensive skewness and approximately 82% of the answers were related to “0” or “Completely disagree”. Furthermore, while there is no compensation for LBP in most of the work places in Iran, item 8 was irrelevant and inappropriate for the Persian version and was removed from analysis. 3.2.2. Reliability The Chronbach’s alpha coefficient for the questionnaire was calculated as 0.89 with α = 0.80 for FABQphysical and α = 0.89 for FABQ-Work. The mentioned values demonstrated adequate internal consistency of the questionnaire. The Test-Retest Reliability was tested on 40 patients. As it is shown in Table 2, the Intraclass Correlation Coefficient (ICC) for physical activity and work subscales were 0.802 and 0.808 respectively. Furthermore the Coefficient of r = 0.805 was estimated for the total questionnaire as an indicator of excellent reliability of the Persian FABQ.
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
217
Table 3 Principal factor analysis of the questionnaires’ items, using Varimax rotation method Principle factors Factor 1 (Variance explained: 45.72%, Eigenvalue: 6.86)
Items 7 9 10 11 12 13 14 15 16
Loading∗ 0.507 0.682 0.629 0.637 0.796 0.772 0.783 0.595 0.678
Mean (SD) 3.72 (1.92) 2.34 (2.05) 3.54 (1.92) 3.40 (1.92) 2.88 (2.19) 2.94 (2.27) 2.73 (2.31) 1.71 (3.49) 0.97 (1.61)
Factor 2 (Variance explained: 12.19%, Eigenvalue: 1.83)
1 2 3 4 5 6 7 10 11
0.707 0.763 0.756 0.735 0.537 0.558 0.599 0.502 0.571
3.93 (1.97) 4.36 (1.80) 4.14 (1.83) 4.73 (1.69) 4.08 (1.87) 3.39 (2.12) 3.72 (1.92) 3.54 (1.92) 3.40 (1.92)
∗ The
items related to each factor were confirmed to be stable if they were loaded above 0.5.
Table 4 Spearman’s rank correlation coefficient of subscales of the FABQ to pain and disability Variable Pain intensity (VAS) LBP induced disability (RMDQ) ∗ Presented
Physical activity∗ 0.260 0.292
Work∗ 0.494 0.418
FABQ (Total)∗ 0.483 0.435
“rho” correlation values are significant at the level of 0.01.
3.2.3. Construct validity Exploratory Factor Analysis (EFA) was carried out on results obtained from 136 patients in order to explore the factor structure of the scale. The analysis determined two factor structures which could explain 57.9% of the total variance (Table 3). These two factors were confirmed using scree-plot method. Comparable to the original version, factor 1 was focused mainly on the fear avoidance beliefs about work. Items 7 through 16 (except item 8 which was excluded) were loaded above 0.5 on this factor with 45.72% of the total variance. Factor 2 which was able to show the relation between fear avoidance beliefs with regard to patients’ physical activity, accounted for 12.19% of the explained total variance. In this factor, items 1 through 6 and 7, 10 and 11 were loaded above 0.5. In this regard, we found that item 6 of the provided Persian FABQ was more compatible with the second factor unlike the original version [12]. Data of the present study also showed that items 7, 10 and 11 which represent the beliefs of the patients about works’ effect on aggregation of the pain, were strongly associated with both factors however their value of loading was higher on the first factor, compared with the second one (Table 3). This result, could explain their higher associa-
tions with the items related to the work subscale. The results of inter-item correlation showed that items 10 and 11 as well as 12 and 13 were strongly correlated (with r = 0.85 and 0.88 respectively). Although, this level of correlation was close to redundancy value [29], these items were preserved unchanged in the analysis. Correlation of the FABQs’ subscales with other clinical variables was carried out to investigate the divergent construct validity of the survey. The FABQ2 (Fear and Avoidance Beliefs about physical activity) showed little or no relationship with VAS (ρ = 0.26, P < 0.001) and RMDQ for measuring disability related to LBP (ρ = 0.29, P < 0.001). The FABQ1 (Fear and Avoidance Beliefs about work) as well as the total questionnaire demonstrated fair relationship to both VAS and RMDQ (Table 4). These findings suggest an acceptable divergent validity of the provided questionnaire.
4. Discussion Fear of pain which leads to avoidance behaviors is much more debilitating than pain severity [14]. Recognition of these behavioral and psychosocial factors
218
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
which are suggested as the main predictors of chronicity, might be helpful to more effectively treat LBP patients and decrease the enormous burden of the disease [12,19,30]. Lack of a standard tool for measurement of these factors could be considered as a major obstacle in the management of LBP patient. While FABQ is known as a reliable and valid tool for evaluation of behavioral and psychosocial affects of LBP on work and physical activity of patients, to our knowledge no validated Persian version of the questionnaire has been still developed. In this study forward and backward translation was performed to translate the original questionnaire into Persian. Conceptual instead of word-for-word translation was aimed to store the meaning of each item and the perception of the whole questionnaire. Although such adaptations may lead to decline disagreements as well as missing data [16], our findings showed that the validated Persian version of FABQ has appropriate psychometric properties. Therefore it is easy to use for assessing fear of pain and avoidance behaviors of Iranian LBP patients as a part of complete evaluation of patients prior to the treatment. In addition, using this standard and validated questionnaire, comparison of the results obtained from Iranian population with international studies as well as meta analysis will be possible [18,31]. 4.1. Reliability In this investigation, the Persian FABQ provided the same values when it was applied repeatedly to the same patient. The test-retest reliability was excellent with an ICC of 0.802 and 0.808 for the items related to physical activity and work domains, respectively. The coefficient of 0.805 was estimated for all items of the questionnaire together. The ICC was comparable to the original study by Waddell et al., (0.74) [12] and other validated versions in French, (ICC: 0.72 for physical activity related subscale and ICC: 0.88 for work related subscale) [18], German (0.87) [19], Spanish (0.96) [1] and Greek (0.86) [20]. The interval between two records of the patients in this study was 15 days. Pfingsten et al. [19] and Kovacs et al. [1], could observe similar satisfactory reliability in their studies which were repeated after 29 days and 14 days of the baseline respectively. According to the current study, the Cronbach’s alpha coefficient of the total questionnaire was 0.89, which demonstrated a high homogeneity of the Persian-FABQ. This result is in consistency with the internal validity of the original (0.82) [12] German (0.91) [19] and Turkish (0.91) [16] versions of the questionnaire.
4.2. Construct validity Construct validity as one of the most important features of a scale, can explain the construct of the developed measure and estimate the correlations. The construct of a scale can be assessed using convergent and divergent validity as well as factor analysis [32]. Due to lack of any previous validated instrument for measurement of fear avoidance beliefs in Iranian population, the convergent validity was not performed in this study. However, divergent validity of the questionnaire was tested to show that the concept concerned in FABQ measure was rather different from what was measured by VAS and RMDQ. In this regard, no correlation between the pain intensity (measured by VAS) and disability (measured by RMDQ) of the LBP patients and their fear avoidance beliefs about physical activity was found. However we found that both the pain intensity and disability of the subjects have fair correlation with the fear avoidance beliefs of the subjects about work. This was in contrast with the results of the original version [12], as well as validated Turkish [16] and French [18] versions of the scale which reported no correlation between two subscales of the questionnaire and pain intensity of subjects. Cultural differences as well as financial support of governmental companies for work absence of employees in Iran, might be the possible explanations of this difference between our results and previous studies. In accordance with the findings of the present study, Waddell et al. [12] reported a significant correlation between the fear avoidance beliefs about work and self-reported disability in performing daily-living activities among LBP patients. It is well documented that pain-related fear might influence the cognition of the patients and lead to hypervigilance of the patients from the possible threats. This fear contributes to augmented psychophysiological awareness to confront with threatening situations [11]. Work related injuries as a threat, might have a profound impact on beliefs and avoidance behaviors of LBP patients about work. In addition, this effect as one of the main predictors of physical performance, may lead to work loss and disability as well as greater perception of pain [11,12]. In this study, to extract the major factors of the questionnaire, the exploratory factor analysis was performed [12,18,19]. The two-factor structure which was extracted from factor analysis of the Persian FABQ, was similar to the original version [12] and studies of Korkmaz et al. [16] and Staerkle et al. [33]. It was rather different from three-factor structure which
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
was reported in validated German and Greek versions. In these two versions, the work subscale known as FABQ1 in our study, was furthermore subdivided into two sections, determined as “Work as a cause” and “Work prognosis” [19,20]. The two-factor structure which was extracted from the provided Persian questionnaire could account for 57.9% of the total variance which was close to the variance explained by Waddell et al. [12] (60.2%). Unlike the original version in which item 1 was excluded due to inconsistent loading, this item had appropriate factor loading in our study and was preserved. Furthermore, items 13, 14 and 16, which were highly correlated items in the original version, had not shown high correlation in the current study and were not excluded [12]. In this investigation, primary approaches in assessment of psychometric properties of the Persian FABQ were performed. There are some points, which are desirable to be evaluated in future surveys. According to the inclusion criteria of the study, the patients with active working status were recruited. This may lead to decline the possibility to generalize the outcomes of the study to some retired, unemployed and house wife patients. As another limitation of the study, we only tested the divergent validity of the Persian FABQ with the pain intensity and disability of the patients. Investigating the correlation between Persian FABQ and other variables including education, occupational status, psychological distress, depression and anxiety should be considered in future studies.
5. Conclusion This study demonstrated that Persian FABQ has adequate reliability and validity. Furthermore, using this questionnaire for assessment of fear avoidance beliefs in Persian LBP patients, as a part of complete evaluation, is really worth considering. Development of this questionnaire will be useful for comparability between Persian and English language studies and facilitates an international collaboration in this field. In addition, development of the Persian version of FABQ will be beneficial for clinical assessment of the subjects with LBP. It is reported by Swinkels-Meewisse et al. [34] that targeting the pain related fear of the subjects with acute stages of LBP is an effective way of preventing the transition of the disease from acute to chronic. Therefore, this questionnaire can help the clinicians to recognize the patients who need psychological interventions for reduction of pain related fear which leads to reduction of the disability of the patients.
219
Ethical approval Before the study, the process and aim of the study were described to the patients. All of the finally enrolled patients signed a written informed consent. Approval of this study was obtained from the Ethical Committee of Tehran University of Medical Sciences.
Funding This study was funded by Tehran University of Medical Sciences.
Conflict of interest There is no conflict of interest.
References [1]
Kovacs, F.M., et al., Psychometric characteristics of the Spanish version of the FAB Questionnaire. Spine, 2006. 31(1): p. 104. [2] Hammill, R.R., J.R. Beazell, and J.M. Hart, Neuromuscular consequences of low back pain and core dysfunction. Clinics in Sports Medicine, 2008. 27(3): p. 449-462. [3] Frymoyer, J. and W. Cats-Baril, An overview of the incidences and costs of low back pain. The Orthopedic Clinics of North America, 1991. 22(2): p. 263. [4] Coste, J., et al., Clinical and psychological diversity of nonspecific low-back pain. A new approach towards the classification of clinical subgroups. Journal of Clinical Epidemiology, 1991. 44(11): p. 1233-1245. [5] Dubois, J.D., et al., Effect of experimental low back pain on neuromuscular control of the trunk in healthy volunteers and patients with chronic low back pain. Journal of electromyography and kinesiology: Official journal of the International Society of Electrophysiological Kinesiology, 2011. [6] Kordi, R. and M. Rostami, Low Back Pain in Children and Adolescents: an Algorithmic Clinical Approach. Iran J Pediatr, 2011. 21(3): p. 259-270. [7] Manchikanti, L., Epidemiology of low back pain. Pain Physician, 2000. 3(2): p. 167-192. [8] Vlaeyen, J.W.S., et al., Fear of movement/(re) injury and muscular reactivity in chronic low back pain patients: an experimental investigation. Pain, 1999. 82(3): p. 297-304. [9] Lethem, J., et al., Outline of a Fear-Avoidance Model of exaggerated pain perception – I. Behaviour Research and Therapy, 1983. 21(4): p. 401-408. [10] Vlaeyen, J.W., et al., Fear of movement/(re)injury in chronic low back pain and its relation to behavioral performance. Pain, 1995. 62(3): p. 363-72. [11] Vlaeyen, J.W.S. and S.J. Linton, Fear-avoidance and its consequences in chronic musculoskeletal pain: a state of the art. Pain, 2000. 85(3): p. 317-332. [12] Waddell, G., et al., A Fear-Avoidance Beliefs Questionnaire (FABQ) and the role of fear-avoidance beliefs in chronic low back pain and disability. Pain, 1993. 52(2): p. 157-168.
220 [13]
[14]
[15]
[16]
[17]
[18] [19]
[20]
[21]
[22]
[23]
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire Klenerman, L., et al., The prediction of chronicity in patients with an acute attack of low back pain in a general practice setting. Spine, 1995. 20(4): p. 478. Crombez, G., et al., Pain-related fear is more disabling than pain itself: evidence on the role of pain-related fear in chronic back pain disability. Pain, 1999. 80(1-2): p. 329-339. de Abreu, A.M., et al., Versão brasileira do Fear Avoidance Beliefs Questionnaire The Brazilian version of the Fear Avoidance Beliefs Questionnaire. Cad. Saúde Pública, 2008. 24(3): p. 615-623. Korkmaz, N., et al., Validation and reliability of the Turkish version of the fear avoidance beliefs questionnaire in patients with low back pain. European Journal of Physical and Rehabilitation Medicine, 2009. 45(4): p. 527. Pei, L., J. Xia, and J. Yan, Cross-cultural Adaptation, Reliability and Validity of the Chinese Version of the Fear Avoidance Beliefs Questionnaire. The Journal of International Medical Research, 2010. 38(6): p. 1985-1996. Chaory, K., et al., Validation of the French version of the fear avoidance belief questionnaire. Spine, 2004. 29(8): p. 908. Pfingsten, M., et al., Validation of the German version of the fear-avoidance beliefs questionnaire (FABQ). European Journal of Pain, 2000. 4(3): p. 259-266. Georgoudis, G., et al., Cognitive assessment of musculoskeletal pain with a newly validated Greek version of the FearAvoidance Beliefs Questionnaire (FABQ). European Journal of Pain, 2007. 11(3): p. 341-351. Mohseni-Bandpei, M.A., et al., Occupational back pain in Iranian nurses: An epidemiological study. Br J Nurs, 2006. 15(17): p. 914-7. Mohseni-Bandpei, M.A., et al., Prevalence and risk factors associated with low back pain in Iranian surgeons. J Manipulative Physiol Ther, 2011. 34(6): p. 362-70. Mousavi, S.J., et al., Low back pain in Iran: A growing need to adapt and implement evidence-based practice in developing countries. Spine (Phila Pa 1976), 2011. 36(10): p. E638-46.
[24]
Wewers, M.E. and N.K. Lowe, A critical review of visual analogue scales in the measurement of clinical phenomena. Research in Nursing & Health, 1990. 13(4): p. 227-236. [25] DeOreo, P.B., Hemodialysis patient-assessed functional health status predicts continued survival, hospitalization, and dialysis-attendance compliance* 1. American Journal of Kidney Diseases, 1997. 30(2): p. 204-212. [26] George, D. and P. Mallery, SPSS for Windows Step-by-Step: A Simple Guide and Reference, 14.0 update (7th Edition). 2006: Allyn & Bacon. [27] Fleiss, J., B. Levin, and M. Paik, Statistical Methods for Rates and Proportions, 3rd Edition. 2003: Wiley. [28] Atkinson, G. and A. Nevill, Comment on the use of concordance correlation to assess the agreement between two variables. 1997, JSTOR. p. 775-777. [29] Tabachnick, B. and L. Fidhi, l 1996. Using multivariate statistics 3rd ed, Harper Collins, New York. [30] Feuerstein, M. and P. Beattie, Biobehavioral factors affecting pain and disability in low back pain: mechanisms and assessment. Physical Therapy, 1995. 75(4): p. 267-280. [31] Guillemin, F., C. Bombardier, and D. Beaton, Cross-cultural adaptation of health-related quality of life measures: literature review and proposed guidelines. Journal of Clinical Epidemiology, 1993. 46(12): p. 1417-1432. [32] Fayers, P.M. and D. Machin, Quality of life: the assessment, analysis and interpretation of patient-reported outcomes. 2007: Wiley. [33] Staerkle, R., et al., Longitudinal validation of the fearavoidance beliefs questionnaire (FABQ) in a Swiss-German sample of low back pain patients. European Spine Journal, 2004. 13(4): p. 332-340. [34] Swinkels-Meewisse, I.E., et al., Fear of movement/(re)injury predicting chronic disabling low back pain: a prospective inception cohort study. Spine (Phila Pa 1976), 2006. 31(6): p. 658-64.
M. Rostami et al. / Validation of the Persian version of the fear avoidance belief questionnaire
Appendix
221
