Validation of the Spanish version of the Burn Specific Health Scale-Brief (BSHS-B) questionnaire

The Burn Specific Health Scale-Brief (BSHS-B) is considered a validated questionnaire to evaluate quality of life after burn. The purpose of this study was to translate the BSHS-B into Spanish and perform its cross-cultural adaptation. First, BSHS-B was translated from English into Spanish. Subsequently, 84 patients answered the Spanish version of BSHS-B and SF-36 scales to assess the reliability (Cronbach’s alpha), construct validity (Spearman rank test), and stability in time (intra-class correlation coefficient). The BSHS-B-Sp showed a good internal consistency with a global Cronbach’s alpha of 0.96. Correlations between the major domains of BSHS-B and SF-36 are reported with Spearman’s coefficient ranging from 0.29 to 0.87 in all sub-domains (p < 0.01). Stability in time was confirmed by intra-class correlation coefficient (0.91–0.99 for every sub-domain and 0.98 for global score, p < 0.001). The Spanish version of the BSHS-B demonstrated an appropriated internal consistency, construct validity, and stability in time. This fact supports its applicability to evaluate the quality of life of burn patients. Level of evidence: Not gradable


Introduction
Burn injuries cause severe physical and psychological sequelae in patients. It affects their self-esteem, their relationships with family and friends, their body image, and their capacities to work are reduced. These affairs have a vital impact on the quality of life (QoL) of patients.
Quality of life assessment is based on the evaluation of different spheres (physical, social, and psychological). The level of reduction of QoL depends on total body surface area (TBSA) involved and certain critical areas such as hands and head burns, which are especially related in physical and social repercussions, respectively.
QoL questionnaires are absolutely useful for physicians to be aware of the level of satisfaction of patients and establish an adequate approach to improve it. In addition, they help patients to know not only their physical and psychological status, but also their needs and progression. They should be easy to read and understand to facilitate QoL evaluation.
The Burn Specific Health Scale-Brief (BSHS-B) is an extremely useful tool with 40 items. Each item is answered from 0 (total) to 4 (nothing at all). It consists of nine sub-domains: affect, simple abilities, work, interpersonal relationships, heat sensitivity, sexuality, treatment regimens, body image, and hand function [1]. As other quality of life scales, higher scores of BSHS-B refer to better quality of life.
Although Sanz et al. [15] published the Spanish version of the Burn Specific Health Scale in 1998, any validated Spanish version of the BSHS-B is actually available. Therefore, the purpose of the study was to validate the translated Spanish version of the BSHS-B, and also testing its reliability and validity in clinical practice.

Materials and methods
The study was held by the Plastic and Reconstructive department of a third level hospital in Spain. All patients were informed about the purpose of the study and accepted to participate. Anonymity was maintained during patient inclusion.
The Short-Form 36 Health Survey Questionnaire (SF-36) and the Spanish version of BSHS-B were delivered at the same time to 84 patients who were previously admitted in our institution from January 2015 to December 2020. Both scales were administered by burn surgeons during hospital visits from June 2020 to August 2021.

Inclusion criteria
We included burn patients > 18 years old suffering full thickness burns equal to or larger than 5% of TBSA who underwent surgery or enzymatic debridement.

Exclusion criteria
We excluded pediatric and psychiatric patients, non-Spanish speakers, and patients with a TBSA < 5% or suffering from superficial burns. Dead and lost to follow-up patients between their discharge and the period of the study were also excluded.

Data collection
In total, 222 eligible burn patients were proposed to join the study by phone, but finally, 84 patients accepted. Demographic and clinical data extracted included age, gender, date of admission, percentage of total body surface area (%TBSA), mechanism of burn injury, location of burn, length of stay (LOS), intensive care requirements, surgical procedures, and complications.

Quality of life scales
The Spanish SF-36 questionnaire [16] and the BSHS-B questionnaire [1] that was translated into Spanish (BSHS-B-Sp) were used to investigate the QoL of burn patients.

Burn Specific Health Scale-Brief (BSHS-B)
The BSHS was created in 1982 in the USA [18] and initially assessed the quality of life through 369 items, later reduced to 114. Subsequently, it was reduced to 80 items (Abbreviated Burn Specific Health Scale, BSHS-A) and then revised by Blalock et al. [19] (Revised Burn Specific Scale, BSHS-R), containing a total of 31 items but it excluded hand function and sexuality.
In 2001, Kildal et al. [1] developed the Burn Specific Health Scale-Brief (BSHS-B) which became one of the most widely used in clinical practice to evaluate QoL in burn patients. It is easy to understand and patients complete it in 10 min approximately. The BSHS-B contains 40 items grouped in 9 sub-domains: heat sensitivity (5 items), work (4 items), simple abilities (3 items), interpersonal relationships (4 items), hand function (5 items), body image (4 items), treatment regimens (5 items), sexuality (3 items), and affect (7 items). Burn patients should score each item on a scale from 0 to 4, where the higher scores, the better quality of life.
Subsequently, Willebrand et al. [20] reported that, with the exception of work sub-domain, all sub-domains can be grouped into 3 internally consistent and well separated domains: affect and relationship domain (interpersonal relationship, sexually, and affect), function domain (hand function and simple abilities), and skin involvement domain (treatment regimens, heat sensitivity, and body image). The work sub-domain can be considered as a separate domain by itself. Mean scores were calculated for the overall scale, for the 3 major domains and for each of the sub-domains.

BSHS-B Spanish version (BSHS-B-Sp)
According to the Scientific Advisory Committee (SAC) of the Medical Outcome Trust (MOT) [21], 3 independent interpreters translated the BSHS-B from the English language into Spanish. Then, we performed a reverse translation from the Spanish version to English by a professional English translator. Not only an adequate translation is enough, but also a cultural adaptation is mandatory, because the different perception of QoL in different countries.

Statistic values
All analyses were performed with the SPSS Statistics 25®. To confirm the reliability of the BSHS-B-Sp, the internal consistency was assessed by Cronbach's alpha for each subdomain and the whole instrument. It is considered appropriate when alpha value is above 0.7 [22]. The construct validity of BSHS-B-Sp was determined by the Spearman correlations with the domains of SF-36, which was chosen as the gold standard measure for quality of life.
The stability in time was assessed by the test-retest method and the intra-class correlation coefficient (ICC). The retest was performed at least at 6 months and an ICC ≥ 0.7 is considered acceptable for this purpose.

Results
A total of 540 patients were admitted during the years 2015-2020 in our burn unit and 222 met the inclusion criteria. Of these, finally 84 patients accepted to participate in the study and completed both questionnaires (BSHS-B Spanish version and SF-36). The period of time since the date of the burn and the quality of life evaluation was 6-69 months (35.3 ± 17.1 months). Sixteen patients completed the BSHS-B twice to assess stability in time (Fig. 1).
The population of study were 84 patients, mostly men (67.9%), with a mean age of 42 years old (42.88 ± 17.89) and an average total body burn surface area (TBSA) of 23% (23.78 ± 17.43 [range: 5-75%]). Table 1 describes the demographic data of the participants. Flame (n = 65, 77.4%) was the most common mechanism of injury and the 75% of cases were accidental.
Mean and median scores in every domain for the SF-36 questionnaire are described in Table 2.
The BSHS-B-Sp showed a good reliability with a global Cronbach's alpha of 0.96. In addition, alpha value resulted ≥ 0.7 for every sub-domain, with the higher scores for Simple abilities, Hand function, Body image, and Affect. Table 3 reports alpha values of each domain of the BSHS-B-Sp. The correlation with SF-36 questionnaire scores allowed to assess the construct validity of BSHS-B. Table 4 reports correlations between the major domains of BSHS-B and SF-36, with Spearman's coefficient ranging from 0.29 to 0.87, all statistically significant (p < 0.01). Highest correlations were found between subdomain Affect of the BSHS-B-Sp and Mental Health (0.87), Social Functioning (0.81), Vitality (0.77), and Role-Emotional (0.77) of SF-36.
The stability of the questionnaire in time was determined by intra-class correlation coefficient (ICC). ICC for test-retest ranged between 0.91 to 0.99 and 0.98 for the whole instrument (Table 5).

Discussion
Although the BSHS complete version was validated to Spanish in 1998 [15], it is not available any Spanish validation of the BSHS-B at this moment. It allows plastic surgeons to assess the quality of life of burn patients in Spanishspeaking population in routine clinical practice (in 12 min approximately).

Reliability, construct validity, and stability in time analysis
The Cronbach's alpha score of the whole instrument (0.96) showed good internal consistency, similarly to previous studies in this field as French (0.93), Italian (0.89), or Chinese (0.97). Every sub-domain obtained at least an alpha value of 0.7 (range 0.70-0.95) as recommended in other publications of the BSHS-B translations [1][2][3][4]23].
Four sub-domains resulted Cronbach's alpha values ≥ 0.93 (Hand function, Simple abilities, Body image, and Affect), suggesting a remarkable rate for internal consistency. However, the lowest alpha value was found in the Work sub-domain (0.70).
Correlations with the SF-36 questionnaire were very useful to investigate construct validity. The BSHS-B-Sp shows good correlations with SF-36 and excellent construct validity. Highest correlations were found between Affect of the BSHS-B-Sp and Mental Health and Social Functioning of the SF-36. As mentioned, physical and psychological dysfunction decrease QoL of patients.
Test-retest reliability has been used in other translations to confirm the stability in time of BSHS-B. Our questionnaire showed high global ICC value of 0.98, resulting in good stability in time. French, Persian, and Hebrew versions presented similar results [2,8,9].

Global BSHS-B-Sp
Length of stay, TBSA, genitalia burns, suicide attempts, surgery necessity, initial escharotomy, complications, and intensive care management have a negative influence on global BSHS-B-Sp scores. These characteristics increase morbidity and have been discussed in the literature [1]. Depression and pain related to anxiety have also a negative impact on quality of life scales [24].

Heat sensitivity
Length of stay, TBSA, upper extremity burns, initial escharotomy, complications, and intensive care management are related to lower scores in subdomain Heat Sensitivity. However, enzymatic debridement is related to better scores, which is according to the literature [25].

Affect
Genitalia and abdomen burns and surgery necessity are associated with lower scores in subdomain Affect. In contrast, male gender is associated with better scores.

Hand function
Initial escharotomy and inhalation injury are associated with lower scores in this subdomain. However, people with hand burns did not show statistically differences, as other studies [24].

Treatment regimens
Initial escharotomy, abdomen burns, complications, and intensive care management are related to lower scores in this subdomain.

Work
TBSA, upper extremity burns, suicide attempts, initial escharotomy, complications, and intensive care management have a negative impact on subdomain Work scores. Dyster et al. [26] showed that returning to work depends on burns severity and type of personality. Those who did not return to work have lower quality of life scores and poor physical and psychological health [27].

Sexuality
Genitalia burns, age, being retired/pensioner and surgery necessity are related to lower scores in this subdomain. The physiological decline of sexual desire in old and retired people could explain these findings.

Interpersonal relationships
Only genitalia burns were associated to lower scores in Interpersonal Relationships. Surprisingly, head and neck burns were not associated to worse scores in this subdomain.

Simple abilities
Length of stay, TBSA, head and neck burns, inhalation injury, complications, and intensive care management are related to worse scores in subdomain Simple Abilities.

Body image
Length of stay, TBSA, lower extremity burns, suicide attempts, surgery necessity, initial escharotomy, and complications are associated with lower scores in this subdomain. However, enzymatic debridement is associated to better results in Body Image.

Limitations
Limitations of the current study must be considered. This study was conducted in one institution and retest method was completed on 16 patients. Nevertheless, the good scores in relation with internal consistency and construct validity make possible to use the BSHS-B Spanish version in clinical practice.

Conclusions
The BSHS-B-Sp reports good results in relation with reliability, construct validity, and stability in time, supporting its application to determine the QoL of burn patients. The use of quality of life questionnaires should be implemented routinely to achieve good results and multidisciplinary approach.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http:// creat iveco mmons. org/ licen ses/ by/4. 0/.