Validation of A Lebanese Arabic Version of the Oswestry Disability Index in Lebanon
Chakib Ayoub1, Elias Elias2, Zeina Nasser3, Rosemary Khoury2 MPH and Ghassan Skaf2
1Department of Anesthesiology, American University of Beirut Medical Center, Lebanon
2Department of Neurosurgery, American University of Beirut Medical Center, Lebanon
3Research Center in Epidemiology, Biostatistics and Clinical Research, Université Libre de Bruxelles, Belgium
Submission: December 12, 2018; Published: March 15, 2019
*Corresponding author: Ghassan Skaf, Division of Neurosurgery, Department of Surgery, American University of Beirut Medical Center, Riad El Solh, 1107-2020, Beirut, Lebanon
How to cite this article: Chakib A, Elias E, Zeina N, Rosemary K MPH, Ghassan S. Validation of A Lebanese Arabic Version of the Oswestry DisabilityIndex in Lebanon . Open Access J Neurol Neurosurg. 2019; 10(2): 555783. DOI: 10.19080/OAJNN.2019.10.555783.
Objective Oswestry Disability Index is the most commonly used score for assessing spinal disorders disabilities. However, no validated Lebanese version of the index was available till the time of initiation of our study. Our aim is to validate and adapt the Saudi Arabia version of the Oswestry Disability Index among the Lebanese population.
Methods: After a cultural adaptation of the Arabic questionnaire, a pilot study was conducted to assess the comprehensibility of the prefinal version. The Lebanese version was tested on 96 patients suffering from low back pain who were assessed by phone call twice within 2 weeks. Internal consistency, test-retest reliability, convergent and discriminant validity were investigated.
Result: The Cronbach’s alfa for the Oswestry Disability Index was 0.87. Factor analysis revealed the presence of one component with eigenvalue exceeding 1, explaining 68% of the variance. The correlation of the Oswestry Disability Index with the Quebec Back Pain Disability Scale and the Roland–Morris Disability questionnaire was 0.97, 0.95 respectively (P<0.001). The Oswestry Disability Index showed excellent test-retest reliability.
Conclusion: The Lebanese Version of the Oswestry Disability Index is reliable and valid tool to assess the functional ability among the Lebanese-speaking population with Low Back Pain.
Keywords: Oswestry Disability Index; Roland Morris Disability; Questionnaire; Quebec back pain; Disability Scale; Low Back Pain; Lebanese population; Validation
Abbrevations: LBP: Low Back Pain; RMQ: Roland Morris Disability Questionnaire; ODI: Oswestry Disability Index; QMS: Quebec back pain Disability Scale; RMDQ: Roland-Morris Low Back Pain Disability; SPSS: Statistical Package for Social Sciences; ICC: Intra-Class Correlation
Low Back Pain (LBP) is one of the most common causes of work absenteeism [1,2]. Its prevalence reaches 15% to 30% among adult population . Self-reported questionnaires are usually applied to evaluate the pain condition, effects on daily life activities and as a measuring tool for outcome whenever subjects undergo medical or surgical intervention. Most popular and widely used assessment tools are the Oswestry Disability Index (ODI) [4-6], Roland Morris Disability Questionnaire (RMQ) and the Quebec back pain Disability Scale (QMS) [7,8]. Largely, these questionnaires were established to survey English speaking populations.
The surge of multicultural research studies precipitated the need to adapt health status measures for use in languages other than the source language. However, questionnaires cannot
be applied directly from one social environment to another by a simple direct translation without validation , mainly due to the variability of disease expression between diverse non-English speaking subjects and in order to accomplish a comparable questionnaire that permits resemblance of data. So far, ODI was validated into different versions, such as German, Spanich, Chinese, Italian [10-13]. but no Lebanese version have been validated till this date. Our aim is to validate and adapt the Saudi Arabia version of the ODI among the Lebanese population.
The study was conducted on 96 adult patients suffering from low back pain who presented to the American University of Beirut between Jan 2012 and Jan 2014. The number of participants met
the preferred sample size of 5-10 times patients per item for
performing exploratory factor analysis . Participants eligible
for the study had to satisfy the following inclusion criteria: age
must be 18 years or older of either gender, could speak and read
the Arabic language, and suffering from low back pain. Exclusion
criteria were psychiatric diseases, pregnant women, nursing
mothers and subjects who are unable to provide informed
consent. Local Ethics Committees approval was obtained from
the institutional review board of the American University in
The ODI is a tool designed and used by clinicians to assess
and quantify disabilities associated with low back pain. It was
published by Fairbank et al. . This index is composed of 10
items, each inclosing six questions scored from a scale of zero to
five. Main categories of the 10 items are classified from 1 to 10 in
the following way: Pain intensity, personal care, lifting, walking,
sitting, standing, sleeping, sexual life, social life and travelling.
Calculation is done in terms of percentage by dividing the total by
50 and multiplying it by 100 once the score is obtained. It ranges
from a zero percent (which refers to no disability) reaching 100
% (which refers to total disability). Scores from 0 to 20% are
categorized under minimal disability; Scores from 20 to 40%
signify moderate disability; Scores from 40 to 60% means severe
disability; Scores from 60 to 80% refer to crippling low back
pain and scores beyond 80% denote an excessive incapacity.
Items of the ODI scale has been translated and adapted to the
Arabic language in Saudi Arabia . A review committee
(two Neuro-surgeons and two epidemiologists) compared the
validated Arabic version with the original English version to
detect misinterpretations and nuances that might have been
missed. This committee discussed translation procedure until
a consensus was reached on discrepancies. The Lebanese
dialect is slightly different from the Saudi and Tunisian one, so
the term referring to pain in Arabic “aalaam” was substituted
with “wagaa” after consensus between committee members.
The prefinal version of the ODI questionnaire was then pilot
tested in a sample of 30 patients (15 males and 15 females) to
check the clarity and readability of all items. Each patient was
asked to identify any words that were difficult to understand. In
addition, the investigator was asked to document any problems
that occurred during the administration of the questionnaire.
Most of the 30 patients considered section 8 (Sex life) in the ODI
translated score as a social taboo, so we decided to omit this
question in the final Lebanese version.
Ninety-six eligible patients provided an informed consent.
One investigator extracted data regarding socio-demographic
characteristics (age, gender, marital status, level of education and
smoking status), body weight and height, clinical data (presence
of chronic disease) and the 9-item ODI questionnaire. In addition,
the Roland-Morris Low Back Pain Disability (RMDQ) and the
score of the Quebec Back Pain Disability Scale (QDS) were used
for convergent validation. The 9-items ODI questionnaire were
read loud and repeated but not modified by the investigator. On
average, the questionnaire was completed by participants within
approximately 4 minutes. To assess test-retest reliability of the
scale, all the participants answered the questionnaire two times.
The time between test and re-test reproducibility examination
averaged approximately 2 weeks.
The Roland-Morris Low Back Pain Disability (RMQ): The
RMQ consists of 24 items related to normal activities of daily
living. Each answer is scaled simply 0 or 1, allotting a range of
scores of 0 to 24, a higher score indicating higher disability .
The Quebec Back Pain Disability Scale (QDS): The QDS
is a 20-item questionnaire where the subject is told to answer
each question on a scale, for each activity there is a scale of 0
to 5. The final outcome is obtained by the sum of the scoring
of the degree of difficulty in performing the 20 daily activities.
These outcomes score within the range of 0 and 100, with higher
numbers representing greater levels of disability .
Data entry and analysis were performed using Statistical
Package for Social Sciences (SPSS) version 22. Descriptive
statistics mainly means were used for continuous variables
while percentages were presented for categorical variables.
Cronbach’s alpha test was used to assess the internal consistency
of the total scale. A coefficient > 0.7 indicated a good internal
consistency. Test-retest reliability was assessed through the
Intra-Class Correlation coefficient (ICC; average measure) item
per item and for the global scale. A good reproducibility was
noted when ICC > 0.7. Prior to an exploratory factor analysis,
the suitability of data was assessed by the Kaiser-Meyer-Olkin
statistic of sampling adequacy and Bartlett’s sphericity test.
Factor analysis was performed using the principal components
analysis to extract factors. The retained factor had eigenvalues
of over 1. Independent factors were obtained using the
varimax rotation method. Convergent validity was assessed by
Spearman’s rank correlations to evaluate whether total OSD
scale were associated with the score of the Roland-Morris Low
Back Pain Disability (RMDQ) and the score of the Quebec Back
Pain Disability Scale (QDS). The results were interpreted as
follows: excellent relationship r > 0.91, good 0.71 - 0.9, moderate
0.51 -0.7, poor 0.31 - 0.5, very poor or null r <0.3. A P-value (twotailed)
of <0.05 was considered statistically significant.
The study included 96 patients, 51% male and 49% female.
The mean age was 67.03 ±11.13 years. The majority of our
patients was married (92.7%) and educated at school for more than 12 years (82.3%). Additional socio-demographic
characteristics of the enrolled population are described in Table
Mean values are presented with their Standard Deviation (SD), and
frequencies in numbers (n) and percentage (%) † Single, widowed and
Exploratory factor analysis was performed including the
9 items of the ODI scale. The Kaiser-Meyer-Olkin statistic of
sampling adequacy exceeded 0.5 (KMO= 0.91) and Bartlett’s
sphericity test was statistically significant (χ²= 721.9, df = 36,
p-value < 0.001) indicating that the samples met the criteria for
factor analysis. Principal component factor analysis revealed
the presence of one component with eigenvalue exceeding 1,
explaining 68% of the variance. The reliability analysis showed a
high Cronbach alpha of 0.87. Table 2 displays the factor loadings
and communality for each item.
The results of the test-retest reliability assessment
demonstrated strong reproducibility of the ODI scales [Intraclass
correlation (95 % CI): overall scale, ICC = 0.975 (0.964-
0.981), P-value <0.001. Item per item reproducibility showed
an excellent correlation coefficient ranging from 0.893 to 0.974
The correlations of our index with the Quebec Back Pain
Disability Scale (QDS) (r = 0.97, P < 0.001) and the Roland-Morris
Low Back Pain Disability (r = 0.95, P < 0.001) were deemed
excellent. The ODI has a good convergent validity (Figures 1-2).
The aim of our study was to evaluate the psychometric
properties of the Lebanese version of the ODI. Our data
demonstrate that it exhibits good psychometric properties
regarding reliability, internal consistency, and construct validity
which is similar to the results of the Saudi Arabian ODI . The
questionnaire revealed to be highly comprehensible by Lebanese
population, requiring only few minutes to be completed, with
a mean time of 3.8 minutes, a period similar to the mean time
needed to complete the ODI in other languages [15,17]. The sex
life question in section 8 was omitted in our version to avoid low
rate response to the sex life question. This question is part of
social taboo in Lebanon that can’t be discussed freely with the
patients. The same step took place in the final Korean version
where they also omitted the sex life question in section 8 .
The Cronbach’s alpha test of the ODI was 0.87, similar to
values reported in other papers suggesting a good internal
validity [11,13,19,20]. Other findings are indicative of good
test-retest reliability. Our study also provide evidence for the
construct validity of the ODI which reveals statistical significance
and positive associations with similar constructs such as the
Quebec Back Pain Disability Scale (QDS) and the Roland-Morris
Disability questionnaire (RMQ). These results were consistent
with previous study conducted by A.S. Algarni et al in KSA that
used the QDS and RMQ to evaluate the construct validity of the
Saudi Arabian ODI . These findings provide strong evidence
in support of the fact that the ODI is a valid measure that
evaluates the functions of patients with LBP.
The limitations of the current study include a risk of selection
bias, since the sample was not randomly selected. Our samples
included only elderly adults recruited from the American
University of Beirut Medical Center; the validation findings
may not be generalizable to adults in Lebanon of different
socioeconomic or regional backgrounds. Future studies should
examine the psychometric properties of the scale with a more
diverse sample. We have also validated the new scale against a set
of measures that have not been validated in Lebanon. However,
nothing could have been done to overcome this problem since
no validated tools exist in Lebanon. Further research would be
required to discuss the ability of the instrument to detect change
over time as a function of clinical intervention. Despite these
limitations, this article is the first trial to evaluate the functional
limitation in LBP in Lebanon. It should help researchers and
clinicians to measure the outcome before and after the treatment.
The Lebanese version of the ODI proved to be reliable, valid
and adequate tool to assess the disability in Lebanese patients
with low back pain. We recommend the use of this Lebanese
version of ODI in clinical practice and scientific research on
Lebanese speaking patients who present with low back pain.
The authors of the manuscript certify that they have NO
affiliations with or involvement in any organization or entity
with any financial interest or non-financial interest in the subject
matter or materials discussed in this manuscript. The authors
declare no conflict of interest.