Validity and reliability of Persian version of the Arm Function in Multiple Sclerosis Questionnaire

Abstract

Introduction

This study aimed to determine the validity and reliability of the Persian version of the Arm Function in Multiple Sclerosis Questionnaire which is a self-report questionnaire for persons with multiple sclerosis (MS).

Method

This methodological study was performed in the following stages: translation, validity, internal consistency, and test–retest reliability of Persian-AMSQ. The Nine-Hole Peg Test (9HPT), Coin Rotation Task (CRT), and Functional Independence Measure (FIM) for construct validity were used. Psychometric testing was done to ascertain the validity and reliability of the questionnaire.

Results

In this study, 155 people with MS participated. There were no major linguistic or cultural difficulties in the translation of AMSQ. Face and content validity confirmed by experts and people with MS. The internal consistency was high (Cronbach’s α = 0.99). Test–retest reliability, as measured with intra-class coefficient, was 0.98. Correlations with 9HPT (r = 0.54), CRT (r = 0.16), and FIM (r = −0.54) were significant (p < 0.05).

Conclusion

The Persian-AMSQ appears to be a valid and reliable questionnaire for measuring upper extremity dysfunction in MS.

Keywords

Multiple sclerosis questionnaire upper extremity test–retest reliability validity

Introduction

Multiple sclerosis (MS) is one of the most prevalent neurological diseases in young adults that has a degenerative, chronic, and disabling nature (Stys and Tsutsui, 2019). More than half of the people with MS possess difficulties with their upper extremity–related dysfunctions even in those who are moderately affected (Bertoni et al., 2015). Limitations in the upper extremity could result in activity limitations and participation restriction (Kierkegaard et al., 2012) and as a result can lead to the dependency of these people on family or caregivers and diminish the quality of life (Noori et al., 2019). Clinical manifestations and courses of MS are heterogeneous based on different regions involved in the central nervous system (Pouramiri et al., 2019). Therapists should determine the exact functional disability of these people based on their severity. Using valid and reliable outcome measures to monitor and check the changes in the person’s status or impact of intervention strategies is necessary.

Patient-reported outcome measures should be incorporated in clinical practice and research to capture the patients’ perspectives of their condition. In addition, these measures consist of benefits with regard to communication between therapists and patients, patient satisfaction, and therapist decision-making (Chen et al., 2013; Valderas et al., 2008). Compared to performance tests, these tools require relatively a short amount of time to determine patients’ perspectives (Rallon and Chen, 2008). Currently, several questionnaires are available to assess hand function. These questionnaires are different from simple to complex, from quantitative to nonquantitative, and standard to nonstandard and alongside their multidimensional. Examples of these questionnaires consist of The Australian/Canadian Osteoarthritis Hand Index (Bellamy et al., 2002), ABILHAND (Penta et al., 1998), the Functional Status Scale (Levine et al., 1993), and the Disabilities of the Arm, Shoulder, and Hand (Hudak et al., 1996). These questionnaires have limitations such as not being specific when they come to be used for persons with MS. For instance, the Australian/Canadian Osteoarthritis Hand Index has 15 questions that are related to pain, disability, and articular stiffness in hand osteoarthritis; and ABILHAND is appropriate for patients with rheumatoid arthritis. Furthermore, none of these questionnaires are unidimensional. They include gender-specific items, they do not contain questions for using in which upper extremity is used, and they do not cover questions about specific problems that MS individuals face.

Arm Function in Multiple Sclerosis Questionnaire

The Arm Function in Multiple Sclerosis Questionnaire (AMSQ) is a novel patient-reported outcome measure that examines the upper extremities’ function of people with MS specifically. This questionnaire includes 31 questions, is unidimensional, and focuses on activity limitation of the arm and hand in the past 2 weeks (Mokkink et al., 2015). AMSQ can be used as an outcome measure in clinical research as well as an evaluation tool to monitor the effectiveness of interventions in clinical settings (Mokkink et al., 2015). Furthermore, wide information about the hand and upper extremity function collection would help healthcare professionals to determine the service needs of persons with MS. The AMSQ is originally developed in Dutch and has been validated in six languages (Dutch, English, German, Spanish, French, and Italian) (Kalkers et al., 2019). The first Dutch version of AMSQ showed satisfying validity, excellent test–retest reliability (reliability coefficient = 0.96, 95% confidence interval 0.94–0.97), standard error of measurement of 6.3 (6.3% of scale range), and smallest detectable changes of 17.5 (on a scale from 0 to 100). Due to the lack of a specific Persian questionnaire to measure hand function in persons with MS, it was decided to provide the Persian version of AMSQ.

The purpose of this study was to develop a Persian version of AMSQ and to evaluate its validity and reliability for usage in clinical and research settings.

Methods

A methodological and cross-sectional study design was employed to develop the Persian version of AMSQ and to examine its validity and reliability in persons with MS. This study was performed in three steps: (1) translation (forward and backward translation), (2) validity (face, content, and convergent validity), and (3) test–retest reliability.

Translation

In the first step, AMSQ was translated into the Persian language based on the Beaton guideline (Beaton et al., 2000). This step contains two sub-steps: (1) forward translation and (2) backward translation. In sub-step one, translation of the questionnaire to the Persian language is done with two independent translators who were fluent in Persian and English. At the joint meeting, which was attended by researchers and translators, the differences in translation phrases between the two translators are discussed. Because of the simplicity of questions of the questionnaire, both of the translators did not report any substantial difference in this sub-step. At the end of the meeting, the first draft of the Persian version of AMSQ was extracted, and then, in sub-step two, it was translated into English (backward translation) by two English language experts who were familiar with the rehabilitation literature and blinded to the original version. Again at a joint meeting, which was attended by researchers and translators, the differences of translation phrases between the two translators were discussed. The English edition of the backward translation is approved by the AMSQ developer (Mokkink) of the questionnaire resulting in the final Persian version of the questionnaire.

Face, content, and convergent validity

In the second step, five participants with MS and 30 experts (two neuroscientists, one nurse, seven physiotherapists, and 20 occupational therapists) by convenience sampling evaluated face and content validity. “The experts were rated face validity in a Likert scale assessing clarity, understandability, relevance, and necessity from 1 (not important at all) to 4 (highly important). The impact score was computed for each item (impact score = frequency% × importance). Face validity was acceptable for >80% agreement rate and impact score >1.5.”

Content validity ratio (CVR) and content validity index (CVI) for all items were computed (Lawshe, 1975). According to the Lawshe model, experts should comment on the necessity of the questionnaire items in a triple Likert scale from “it is necessary,” “it is useful but not necessary,” and “unnecessary.” Then, the CVR is calculated with the following formula

CVR = \frac{N_{e} - (N / 2)}{N / 2}

Then, the modified questionnaires were returned to the experts to analyze the items about relativity, simplicity, and clarity using a 4-point Likert scale from 1 (the lowest) to 4 (the highest). Afterward, the CVI is computed for each item with the following formula

CVR = \frac{Number of experts who rated the item as 3 or 4}{Number of experts}

Convergent validity of Persian-AMSQ is assessed by the degree to which the sum score of it was consistent with predefined hypotheses regarding correlations between the Persian-AMSQ and Functional Independence Measure (FIM), Nine-Hole Peg Test (9HPT), and Coin Rotation Task (CRT). Moreover, the 3 hypotheses are as follows: (1) A moderate correlation is expected between the Persian-AMSQ and 9HPT because 9HPT focuses on hand function and dexterity and Persian-AMSQ assesses the whole upper extremity, (2) moderate-to-low correlation is expected between the AMSQ and CRT because the CRT focuses more specifically (even more than 9HPT) on the hand and finger dexterity, and (3) moderate-to-low correlation is expected between Persian-AMSQ and FIM because they measure the non-similar construct.

Reliability

At the final step of this research, test–retest reliability and internal consistency were evaluated. Test–retest reliability defines as the extent to which scores on the AMSQ for stable patients who have not changed were the same for repeated measurement. To evaluate the test–retest reliability of AMSQ, 30 participants with MS who had inclusion criteria completed the demographic questionnaire and AMSQ. Inclusion criteria included diagnosis of MS by a neurologist, over 18 years of age, reporting of hand dysfunction, and understanding Persian language. Exclusion criteria included not being in the acute phase of the disease and having no cognitive impairment that is determined by a neurologist. Convenience sampling was used for recruiting MS participants. In this study, 2-week interval was used to evaluate the test–retest reliability of AMSQ. The internal consistency of Persian-AMSQ was assessed using Cronbach’s alpha.

Measures

The demographic questionnaire was used to collect information about age, gender, types of MS, and Expanded Disability Status Scale (EDSS) scores between 0 and 7.

AMSQ is a novel questionnaire with 31 items about upper extremity function that was developed by Mokkink and colleagues in 2015 using the item response theory method (Mokkink et al., 2015). In 2016, van Leeuwen and colleagues evaluated construct validity and reliability of AMSQ through classical test theory (Van Leeuwen et al., 2017). It is a unidimensional questionnaire that includes items about hand and upper extremity function in the past 2 weeks, and the answers were in Likert scale from 1 to 6—not at all (1), a little (2), moderately (3), quite a bit (4), extremely (5), and no longer able to (6). Higher scores indicated higher limitation in arm function. It looks less than 10 min to administer the test.

FIM questionnaire includes 18 activities of daily living (ADL) and examines functional independence level in individuals. Test items divide into two main sections, consisting of 13 motor function items and five cognitive function items. Test–retest reliability, inter-rater validity for the total scores, and subscales of this test in the Iranian stroke patient population were reported to be between 0.88 and 0.98 (Naghdi et al., 2016). A total FIM score cutoff point of 63 was observed as the optimal level to discriminate patients with adverse events among those with acute stroke (Kurokawa et al., 2018). It took approximately 30 min to administer (Pashmdarfard and Azad, 2020).

The 9HPT is a powerful gold standard test for the evaluation of hand dexterity that was first introduced by Kellor (1971). The test was included in Multiple Sclerosis Functional Composite by Multiple Sclerosis International Society in 2001. 9HPT involves twice placing and removing nine pegs in a pegboard with both the dominant and nondominant hands as well as the time of each test is recorded. The inter-rater reliability and test–retest of this test were reported high (r = 0.86, 0.98) (Feys et al., 2017).

The CRT is a simple, easy, and cost-effective measure that administrates in neurologic conditions to evaluate psychomotor processing speed. In CRT, the patients should rotate a coin through a serial 180° for 10 s. Cutoff points of CRT were reported 18.75 and 19.25 s for dominant and nondominant hands in people with MS, respectively (Heldner et al., 2014).

Procedure

MS patients with a diagnosis made by a neurologist were recruited and classified as relapsing–remitting multiple sclerosis, primary progressive multiple sclerosis (PPMS), secondary progressive multiple sclerosis (SPMS), and progressive–relapsing multiple sclerosis (RRMS, PPMS, SPMS, and PRMS) by convenience sampling in Isfahan, Iran. 155 MS patients participated in this study. The demographic questionnaires and AMSQ were completed by the MS participants, and a trained occupational therapist was administered performance tests. All of the questionnaires and performance tests were completed in one session.

Ethical approval

This study was approved by University Research and ethics committee. After the explanation of the study’s purpose, a written consent form was obtained from all participants in the study, and they were assured that their information was kept confidential.

Statistical analysis

All data were analyzed using IBM SPSS 22 software. Descriptive statistics were used to summarize data. To measure convergent validity, Spearman’s rho correlations were used between the AMSQ and FIM, 9HPT, and CRT scores and interpreted as low, <0.30; moderate = 0.30–0.59; and high, ≥0.60 (Cohen, 1988). Intra-class coefficient (ICC) with a two-way random effects model and 95% confidence interval was used to analyze test–retest reliability data. The minimum standard recommended for reliability is an ICC value of 0.70 (De Vet et al., 2006).

Results

Patient characteristics

Participants of this study contained 155 individuals with MS in Tehran and Esfahan cities in Iran. Thirty-two men and 123 women with a mean age of 40.78 ± 0.88 participated in this study. According to EDSS scores, the women were mildly disabled, and the men were moderately disabled. The demographic characteristics of these participants are presented in Table 1.

Table 1.

Demographic and clinical characteristics of MS participants.

	Female (n = 123)	Male (n = 32)
Age	40.10 (8.91)	43.40 (8.41)
EDSS	2.91 (1.38)	4.04 (1.45)
Marital status		n (%)
Single		33 (21.3)
Married		112 (72.3)
Divorced or widowed		10 (6.5)
Educational level
Under diploma		23 (14.8)
Diploma		66 (42.6)
Postgraduate		66 (42.6)
Occupational status
Unemployed		42 (27.1)
Employed or housewife		113 (72.9)
Multiple sclerosis types
RRMS		95 (61.3)
PPMS		24 (15.5)
SPMS		30 (19.4)
PRMS		6 (3.9)
		Mean (SD)
AMSQ		63.75 (34.45)

MS: Multiple Sclerosis; EDSS: Expanded Disability Status Scale; RRMS: Relapsing–Remitting Multiple Sclerosis; PPMS: Primary Progressive Multiple Sclerosis; SPMS: Secondary Progressive Multiple Sclerosis; PRMS: Progressive–Relapsing Multiple Sclerosis; AMSQ: Arm Function in Multiple Sclerosis Questionnaire.

Translation and validity

The AMSQ translation resulted in slight changes in words clarified by experts. An example of such clarification was to say a bottle of mineral water instead of a bottle of soft drink. The experts who were determined face and content validity had an average age of 34.40 (SD = 5.89) years and an average work experience of 11.43 (SD = 3.71) years. Eighteen of them had a doctorate and 12 of them had a master’s degree, and 20 were women. The MS patients who were participated in face validity had a mean age of 37.20 (SD = 12.85), and four were women. Two had a bachelors’ degree, two had a diploma, and one was under a diploma. All items showed an acceptable impact score (>80% agreement rate and impact score >1.5). Therefore, Persian-AMSQ has good face validity from the perspective of patients and experts to use in the target population. This matter could be because of the words and questions used in AMSQ that were very short, clear, and simple and just asked participants to what extent MS has limited the hand and upper extremity function to do different ADL in the past 2 weeks. The final version of this questionnaire was approved by the developer of the questionnaire. The results of this step indicate that all items in the questionnaire showed acceptable CVI and CVR scores. It should be noted that CVI > 0.79 considered to be acceptable (Yaghmaei, 2003) and the minimum acceptable CVR score for 30 experts is 0.33 (Lawshe, 1975). The overall CVI of the Persian-AMSQ was 0.92.

The mean and standard deviation results of the research variables and the Spearman correlation with the Persian-AMSQ score are demonstrated in Table 2 and Figures 1–3. As it was expected, moderate correlation coefficients were found between Persian-AMSQ, 9HPT, and CRT, and low correlations were found between Persian-AMSQ score and FIM.

Table 2.

Mean, standard deviation, and correlation of study variables.

Variable	Mean (SD)	R	p-value
9HPT dominant	29.24 (26.81)	0.545	0.001^a
9HPT nondominant	37.04 (50.96)	0.472	0.001^a
CRT dominant	24.52 (22.38)	0.160	0.046^b
CRT nondominant	24.29 (19.77)	0.194	0.016^b
FIM	105.81 (17.70)	−0.542	0.001^a

r: correlation coefficient; 9HPT: Nine-Hole Peg Test; CRT: Coin Rotation Task; FIM: Functional Independence Measure.

^aCorrelation is significant at the 0.01 level (2-tailed).

^bCorrelation is significant at the 0.05 level (2-tailed).

Figure 1.

Correlation between Persian-AMSQ and NHPT dominant hand. AMSQ: Arm Function in Multiple Sclerosis Questionnaire. NHPTD: 9 Hole Peg Test for Dominant hand.

Figure 2.

Correlation between Persian-AMSQ and CRT dominant hand. AMSQ: Arm Function in Multiple Sclerosis Questionnaire; CRT: Coin Rotation Task.

Figure 3.

Correlation between Persian-AMSQ and FIM. AMSQ: Arm Function in Multiple Sclerosis Questionnaire; FIM: Functional Independence Measure.

Reliability

The mean and standard deviation of scores in test and retest and test–retest reliability are presented in Table 3. The internal consistency of the items was measured high (Cronbach’s α = 0.99). Also, the average inter-item correlation was 0.98.

Table 3.

Mean and standard deviation of scores in test and retest and test–retest reliability.

	Mean (SD) of test	Mean (SD) of retest	95% CI	ICC	p-value
Total score of AMSQ	75.50 (42.17)	74.43 (43.52)	0.96–0.99	0.98	0.001

AMSQ: Arm Function in Multiple Sclerosis Questionnaire; CI: confidence interval; ICC: intra-class coefficient.

Discussion

This study was designed to translate AMSQ into Persian and investigate its validity and reliability in a group of experts and patients with MS. Persian-AMSQ is a patient-reported outcome measure to evaluate hand and upper extremity function and its impact on ADL and quality of life in Persian-speaking people with MS.

Validity

In the present study, the translation was performed according to the Beaton guideline and was recommended by the developer. Furthermore, the final version was approved by her. The results indicated that Persian-AMSQ has a good face and content validity.

All of the hypotheses that have been formulated for construct validity were confirmed. As the score of the Persian-AMSQ increased, the score of the 9HPT test and CRT increased and the score of the FIM decreased. As was expected, the Persian-AMSQ showed moderate correlation with 9HPT, moderate-to-low correlation with CRT, and moderate-to-low correlations with FIM. Moderate to the low correlation between Persian-AMSQ, 9HPT, and CRT might be due to their focus. These two performance tests focus specifically on hand and finger dexterity, while Persian-AMSQ assesses the whole upper extremity. A moderate correlation of Persian-AMSQ and FIM might be due to the factors that they assess. FIM is not specific for assessing upper extremity functioning and includes subtests such as sphincter control, transfer, locomotion, communication, and cognitive. In this study, a lower correlation between AMSQ and 9HPT in comparison to other studies is found. The results of Dutch (Van Leeuwen et al., 2017) and German (Steinheimer et al., 2018) showed high correlations between AMSQ, 9HPT, and also between AMSQ and CRT. In the Dutch and German versions, the correlations between the AMSQ score and 9HPT were 0.77 and 0.83, respectively, and both were 0.77 in the CRT. In the Italian version, the correlation score between AMSQ and FIM was high (r = −0.6), and its correlation with ABILHAND that evaluates a similar construct was also high (r = −0.79) (Tacchino et al., 2020).

Reliability

The reliability of the Persian-AMSQ is excellent for use in group comparisons as well as individual-level comparisons. This result is similar to the results of other studies. The result of the Dutch version (ICC = 0.96), the German version (ICC = 0.95), and the Italian version (ICC = 0.96) are similar to the results of the present study (Steinheimer et al., 2018; Tacchino et al., 2020; Van Leeuwen et al., 2017).

The internal consistency of the results of this study was high (Cronbach’s α = 0.99) that reflects the homogeneity of the Persian-AMSQ. The reason for this consistency may be because these patients have lost their ability to do daily functions or adapted to perform them. As a result, there is not much change in scores between test and retest. Also, the activities selected in this questionnaire were chosen from the daily activities that the patients are dealing with, have to do them, and over time have coped with these activities, and therefore, the reliability of the questionnaire has been significantly increased. Cronbach’s α in the study in six countries was 0.98 for Spanish, Italian, and English as well as 0.99 for French and German (Kalkers et al., 2019).

Limitations and strengths of the study

Most of our participants had a relapsing-remitting subtype of MS and low EDSS scores, and therefore, they did not have a severe hand and upper extremity dysfunction and spasticity. This limitation can decrease the generalization of our results. Future studies with patients with an advanced disability might further support the validity of Persian-AMSQ.

The strengths of this study are the use of valid methods for translation and validation processes, set of standard clinical examinations and performance tests to determine the construct validity, and adequate heterogeneous sample size that includes all types of MS.

Conclusion

This study showed excellent results on the validity and reliability of the Persian version of AMSQ for persons with MS and can provide useful information about the hand and upper extremity function. This questionnaire has a moderate level of convergent validity and a high level of reliability.

Key findings

The Persian-AMSQ is applicable for clinical and experimental settings for people with MS and could provide useful information about the hand function of these individuals.

Persian-AMSQ has validity, construct validity, and acceptable reliability.

What the study has added

The convergent validity of AMSQ is clarified by comparing it with FIM, 9HPT, and CRT.

The reliability of AMSQ is confirmed by internal consistency and test–retest.

Footnotes

Acknowledgements

We are grateful to the clients for participating in this study. We also thank the staff at the Isfahan MS Society, Isfahan, Iran. We also thank Dr Mina Ahmadi Kahjoogh for her useful advice on drafting this work.

Research ethics

After explanation of the purpose of the study, a written consent form was obtained from all participants in the study, and they were assured that their information was kept confidential. This study was approved by the Ethics Committee of the University of Social Welfare and Rehabilitation Sciences under the code of ethics IR.USWR.REC.1396.319.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by Tehran University of Social Welfare and Rehabilitation Sciences.

ORCID iD

Sara Afshar

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