German translation, cultural adaption and validation of the unidimensional self-efficacy scale for multiple sclerosis: a study protocol

Exploring the Major Barriers to Physical Activity in Persons With Multiple Sclerosis: Observational Longitudinal Study

BACKGROUND

Physical activity (PA) represents a low-cost and readily available means of mitigating multiple sclerosis (MS) symptoms and alleviating the disease course. Nevertheless, persons with MS engage in lower levels of PA than the general population.

OBJECTIVE

This study aims to enhance the understanding of the barriers to PA engagement in persons with MS and to evaluate the applicability of the Barriers to Health Promoting Activities for Disabled Persons (BHADP) scale for assessing barriers to PA in persons with MS, by comparing the BHADP score with self-reported outcomes of fatigue, depression, self-efficacy, and health-related quality of life, as well as sensor-measured PA.

METHODS

Study participants (n=45; median age 46, IQR 40-51 years; median Expanded Disability Status Scale score 4.5, IQR 3.5-6) were recruited among persons with MS attending inpatient neurorehabilitation. They wore a Fitbit Inspire HR (Fitbit Inc) throughout their stay at the rehabilitation clinic (phase 1; 2-4 wk) and for the 4 following weeks at home (phase 2; 4 wk). Sensor-based step counts and cumulative minutes in moderate to vigorous PA were computed for the last 7 days at the clinic and at home. On the basis of PA during the last 7 end-of-study days, we grouped the study participants as active (≥10,000 steps/d) and less active (<10,000 steps/d) to explore PA barriers compared with PA level. PA barriers were repeatedly assessed through the BHADP scale. We described the relevance of the 18 barriers of the BHADP scale assessed at the end of the study and quantified their correlations with the Spearman correlation test. We evaluated the associations of the BHADP score with end-of-study reported outcomes of fatigue, depression, self-efficacy, and health-related quality of life with multivariable regression models. We performed separate regression analyses to examine the association of the BHADP score with different sensor-measured outcomes of PA.

RESULTS

The less active group reported higher scores for the BHADP items Feeling what I do doesn't help, No one to help me, and Lack of support from family/friends. The BHADP items Not interested in PA and Impairment were positively correlated. The BHADP score was positively associated with measures of fatigue and depression and negatively associated with self-efficacy and health-related quality of life. The BHADP score showed an inverse relationship with the level of PA measured but not when dichotomized according to the recommended PA level thresholds.

CONCLUSIONS

The BHADP scale is a valid and well-adapted tool for persons with MS because it reflects common MS symptoms such as fatigue and depression, as well as self-efficacy and health-related quality of life. Moreover, decreases in PA levels are often related to increases in specific barriers in the lives of persons with MS and should hence be addressed jointly in health care management.

German translation, cultural adaptation and validation of the unidimensional self-efficacy scale for multiple sclerosis

Background

Self-efficacy concerns individuals’ beliefs in their capability to exercise control in specific situations and complete tasks successfully. In people with multiple sclerosis (PwMS), self-efficacy has been associated with physical activity levels and quality of life. As a validated German language self-efficacy scale for PwMS is missing the aims of this study were to translate the Unidimensional Self-Efficacy Scale for Multiple Sclerosis (USE-MS) into German, establish face and content validity and cultural adaptation of the German version for PwMS in Austria. A further aim was to validate the German USE-MS (USE-MS-G) in PwMS.

Methods

Permission to translate and validate the USE-MS was received from the scale developers. Following guidelines for translation and validation of questionnaires and applying Bandura’s concept of self-efficacy, the USE-MS was forward-backward translated with content and face validity established. Cultural adaptation for Austria was performed using cognitive patient interviews. Reliability was assessed using Cronbach’s alpha, Person separation index and Lin’s concordance correlation coefficient. Rasch analysis was employed to assess construct validity. Comparison was made to scales for resilience, general self-efficacy, anxiety and depression, multiple sclerosis fatigue and health-related quality of life. Data were also pooled with an historic English dataset to compare the English and German language versions.

Results

The translation and cultural adaptation were successfully performed in the adaptation process of the USE-MS-G. Pretesting was conducted in 30 PwMS, the validation of the final USE-MS-G involved 309 PwMS with minimal to severe disability. The USE-MS-G was found to be valid against the Rasch model when fitting scale data using a bifactor solution of two super-items. It was shown to be unidimensional, free from differential item functioning and well targeted to the study population. Excellent convergent and known-groups validity, internal consistency, person separation reliability and test-retest reliability were shown for the USE-MS-G. Pooling of the English and German datasets confirmed invariance of item difficulties between languages.

Conclusion

The USE-MS-G is a robust, valid and reliable scale to assess self-efficacy in PwMS and can generate interval level data on an equivalent metric to the UK version.

Trial registration

ISRCTN Registry; ISRCTN14843579; prospectively registered on 02. 01. 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02183-y.

Selected psychometric aspects of the Polish version of the Liverpool Self-efficacy Scale

Background

Self-efficacy expresses the individual’s belief in their ability to take up and continue actions in order to achieve a particular result and cope with various life events. For people with multiple sclerosis (MS), self-efficacy is an im-portant resource because it affects how they adapt to the disease, and influences their motivation, health-related behavior and physical activity. It also has a great impact on their quality of life. Because of the lack of tools for meas-uring self-efficacy in Polish patients with multiple sclerosis, the goal of the current study was to develop a Polish language version of the Liverpool Self-efficacy Scale (LSES) and assess its validity and reliability.

Participants and procedure

A total of 175 people diagnosed with MS took part in the study. A Polish version of the LSES, the Sense of Coherence Questionnaire (SOC-29), the Resiliency Assessment Scale (SPP-25), the Health-Related Hardiness Scale (HRHS), the Acceptance of Illness Scale (AIS) and the Multiple Sclerosis Impact Scale were applied.

Results

Confirmatory factor analysis, reliability analysis using α and ω coefficients, and two measures of validity (content and criterion validity) were used in order to validate psychometric properties of the Polish version of the LSES. Our analyses confirmed a good fit of the one-factor and two-factor models.

Conclusions

The results indicate that the Polish version of the LSES is a useful and valuable tool for assessing levels of self-efficacy in Polish patients with multiple sclerosis. The scale can be used for both clinical and research purposes.