Cross-cultural adaptation of the City Birth Trauma Scale for the Brazilian context

Abstract Background: Posttraumatic stress disorder consists of a set of symptoms that occurs in response to one or more traumatic events and can occur in postpartum, from traumatic situations related to the birth or to the baby’s health in the first days of life. It is important tracking the presence of birth trauma, but there is not available instruments in the Brazilian context for this purpose. Objectives: To present the cross-cultural adaptation of City Birth Trauma Scale (BiTS) into Brazilian portuguese. Methods: Cross-cultural adaptation involved independent translations, synthesis,back-translation, and submission to the original author’s appreciation. After the scale was subjected to face validity, followed by a pilot study with postpartum mothers. Results: All steps were performed for the cross-cultural adaptation. Regarding face validity, items evaluated concerning different types of equivalence, presented satisfactory agreement values (≥4.20). Most of the expert’s suggestions were followed, being the main ones related to adjustments in prepositions, pronouns and verbal subjects. Pilot study showed that the mothers had been able to understand and respond to the instrument without adjustments. Discussion: BiTS’s Brazilian version proved to be cross-culturally adapted, ensuring the possibility of intercultural data comparison from the semantic, idiomatic, cultural, and conceptual perspectives. New studies are being conducted to attest its psychometric adequacy.


Introduction
Posttraumatic stress disorder (PTSD) can be characterized according to the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as a set of symptoms that occur in response to traumatic events lasting longer than one month which involve: a) exposure to one or more traumatic episodes experienced directly or witnessed; b) presence of intrusive symptoms such as recurrent and involuntary memories, dreams, flashbacks, intense suffering or physiological reactions; c) a persistent avoidance pattern to stimuli associated with the traumatic event; d) negative changes in cognition and mood; e) changes in arousal and reactivity associated with the traumatic event; f) experience of suffering and social or professional losses 1 .
When experienced in the postpartum period, PTSD may arise from traumatic situations related to the moment of the delivery or the baby's and/or mother's health after the first days of life 2 . A traumatic birth can be defined according Scarabotto & Riesco 3 , as one or more events that occur during labor and/or childbirth, in which the postpartum woman faces intense fear, helplessness, loss of control and involves injury (real/imaginary) and/or death of the newborn 4 .
Prevalence studies in Brazil show that postpartum PTSD affects about 5%-9% of women with high-risk pregnancies and 3% of those with low-risk pregnancies 2,5,6 . The impacts associated with PTSD in the postpartum period are multiple, highlighted among them: intense feelings of distress and helplessness experienced by the mother , impairment of maternal and child bonding, besides the appearance of diverse comorbidities, such as generalized anxiety, panic, and substance abuse disorders 7,8 .
Given the severity and the countless losses associated with this type of trauma, the need to identify and treat it is becoming increasingly urgent. However, until recently there were no specific instruments for screening and/or assessment of trauma at birth. This assessment was made through more general instruments, as in the study by Henriques et al. 2 , which assessed the presence of PTSD at birth using the Trauma History Questionnaire and Posttraumatic Stress Disorder Checklist.
More recently this gap was filled by the City Birth Trauma Scale (BiTS) that had been proposed by Ayers et al. 9 . It is a self-report instrument, composed of 35 items, and the higher the scores, the higher the PTSD severity indicators. It stands out for being based on the DSM-5 criteria and has the specific objective of assessing the presence/absence of PTSD symptoms at birth, as well as its severity. The original psychometric study, conducted with 950 postpartum women, showed bifactorial structure (birth-related/general symptoms), excellent reliability (α = 0.92) and a high association with distress, unpaired functioning, and desire for treatment (r = 0.50-0.61) 10 . Other than that, it had already been translated and validated into Hebrew 11 and Croatian 10 , in which their psychometric qualities were also replicated.
To our knowledge, there are no available instruments to assess PTSD associated with birth in the Brazilian context. Thus, considering the severity and negative impact of this condition, resources are needed to briefly track and direct potential cases. In this context, BiTS becomes a promising instrument, which justifies its translation and conducting psychometric studies for Brazil. This study aimed to perform the cross-cultural adaptation of BiTS to the Brazilian context, as well as evaluating its content/face validity.

Methods
The study was approved by the local Ethics Committee (No.17646/ 2014), and the cross-cultural adaptation was initiated after approval by the original author of the scale.
The translation and adaptation process of BiTS into Brazilian Portuguese was based on Beaton et al. 12 : initial translation, synthesis of translations, back-translation, peer review, and pre-test. The translation phase was assisted by three bilingual professionals specialized in different fields: psychology(KPL), neuroscience(RGS) and linguistics (JTS), who independently translated the instrument from English to Portuguese. A summary version of the three translations (VS1) was later made to resolve discrepancies and to select the terms considered most appropriate to the Brazilian context by two psychologists with previous experience in the fields of psychometrics and psychological evaluation, who filled the role of judge (FLO/MFD). VS1 was back-translated by another bilingual Brazilian psychologist with experience in psychopathology (JPMS). The back-translated version was submitted for initial consideration by the original author of the scale. After the author's considerations, and her endorsement, we moved to the content validity stage. To this end, a committee of experts was created, composed of a psychologist (CMG) and four psychiatrists, researchers and university professors (TAD/PNOB/AC/LDMS), who analyzed the conceptual, semantic, idiomatic, and cultural equivalence of each structure of the instrument. Analyzes were performed independently by each expert, who were instructed to rate each item according to the following scale: 1 ("not equivalent") to 5 ("very equivalent"), besides commenting/suggesting changes or adjustments based on that scoring. The content validity coefficient (CVC) 13 was calculated for each item of the instrument and the instrument as a whole. The cutoff score of ≥ 0.70 was adopted as satisfactory 14 .
The experts' comments were examined by the judges and the relevant suggestions were accepted, and the final version of the instrument was drafted, which was again appreciated and approved by the original author.
Pilot study was conducted with the target population (mothers with gestation in the last year). For this purpose, a sample of 16 women aged 19 to 39 years old (mean = 30.81; SD = 6.34) and different educational levels (18.8% ≥ 9 years of study) to respond to the instrument. The participants were instructed to read the instructions, response alternatives, and each item on the scale. Afterward, the comprehension/understanding was verified, as well as the adjustment suggestions.

Results
All BiTS translation process from English to Brazilian Portuguese can be viewed in Supplementary Material S1.
Regarding content validity conducted by the experts, all items evaluated concerning the different types of equivalence presented average agreement values higher than 4.20.
As shown in Table 1, all evaluated structures had a CVC ≥ 0.84, regardless of the equivalence type evaluated. The total CVC of the instrument for the different equivalences was 0.98.
Regarding the suggestions made by the experts, these were few. Below are those incorporated in the original version. In the title in Portuguese, the expression "Traumas no Nascimento" was changed to "Traumas no Nascimento" to fit the preposition to time in the English version. In the structures with the expression "nascimento do bebê" only the word "nascimento" was used to remain faithful to the original instrument ("after birth") (instruction 1, question 2, observation 1, 2, items 3, 4, 6-12).
In question 2, fits were made to maintain the temporal clarity of the events, leaving the final formulation for "Durante o trabalho de parto, nascimento e imediatamente após".
In the Portuguese version, the verb "pensou" in items 1 and 2 was replaced with the verb "acreditou" since the latter more accurately portrays the meaning of the word "belief" (being convinced of the truth, existence, or occurrence of a fact). In item 13, this change was made inversely, to remain true to the meaning of the original word "thinking".
The word "relembrar" in item 5 was replaced with the original English term "flashbacks" since this word was also adopted in the portuguese version of the DSM-5. Although the manual is mainly used by professionals with a higher educational level, the pilot project signaled its understanding by the target audience.
In item 34, the word "socializar" was replaced with the expression "estar com as pessoas" to detail the meaning of the term. Finally, items 28 and 32 included the personal pronoun "Eu" at the beginning of the sentence to be faithful to the original version in English.
Given these fits, the new version was once again sent to the original author, who recognized it as the instrument's official version for brazilian portuguese. The Brazilian version was called the "City Escala de Trauma ao Nascimento" and is in full in the Supplementary Material S2.
In the pilot study, no suggestion of major modification was indicated by the respondent sample. All participants showed an understanding of all structures and considered the scale presentation and layout appropriate.

Discussion
The BiTS is designed to evaluate PTSD symptoms associated with childbirth according to DSM-5 criteria. It is the only specific scale for assessing the disorder associated with this type of traumatic situation and has already been of interest to researchers from other cultures, who have also performed the instrument's cross-cultural adaptation to Hebrew and Croatian 10,11 , signaling cross-cultural evidence as presented herein.
For the process of cross-cultural adaptation of this instrument, we followed all steps of the method proposed by Beaton et al. 12 , which is considered the gold standard for health studied mainly because it involves a series of methodological care to ensure the adequacy of the process. These include the translation team composed of translators with different backgrounds, which favors the adjustment to the great Brazilian cultural diversity. The experts' suggestions were included in the final version of the instrument and, although few, they contributed to the better cross-cultural adaptation of the scale to the Brazilian context. Furthermore, the evaluated structures in the instrument had a CVC value ≥ 0.83, which reinforces the evidence of the adaptation stages adequacy, now from the quantitative perspective. Besides, the original author's guidance and contributions at different stages were very important for the development of this procedure, as was the pilot test in the target population.
As a conclusion, the BiTS scale was adapted to the Brazilian context and had its content validity measured. As a next step, it is necessary to test the other validity and reliability indicators to confirm the broader psychometric adequacy of the instrument. BiTS in its Brazilian Portuguese version can be used without the author's permission, either for the clinical context or for research, by quoting the source.

Research support
National Council for Scientific and Technological Development

Conflicts of interests
The authors declare no conflicts of interest.