Psychometric properties of the North American version of the Flodén ATODAI (Attitudes Toward Organ Donor Advocacy Instrument): a validation study

Background: Intensive and critical-care nurses are the key to successful donor management in the critical-care setting. No studies measuring attitudes toward organ donor advocacy existed before 2011, when the 51-item Swedish “Attitudes Toward Organ Donor Advocacy Scale” was developed. The aim of this study was to translate, adapt and establish the psychometric properties of the North American version of the Flodén ATODAI (Attitudes Toward Organ Donor Advocacy Instrument) in terms of validity and reliability. Methods: A multi-step approach was used: Initial translation; Back-translation; Review and synthesis of these translations; Expert panel (N=7) rated the prefinal version of the instrument for content validity index (CVI); International panel made adjustments guided by the expert panel . Reliability testing with test and retest of the adjusted 46-item version was conducted using intraclass correlation coefficient (ICC), weighted kappa ( ҡ Weight ), sign test, and Cronbach’s alpha coefficient (α), (N=50); and finally Delphi technique procedure with a preselected Delphi panel (N=15). Results: The CVI was determined to be greater than the 0.05 significance level. Item level (I-CVI) ranged 0.82-1.0, with a mean of 0.97. Scale level (S-CVI) on the entire instrument was 0.97. Test-retest procedure was performed to estimate stability. In total, 34 of the items had good-to-high ICC. Accepting an ICC of >0.70 resulted in a total of 24 items. Homogeneity reliability was estimated by α and was calculated for these items where α=0.90. In total, 20 of the items had a substantial or almost perfect ҡ Weight and 23 showed a moderate ҡ Weight . None of the items showed systematical differences. The Delphi technique procedure was used on the 22 items with ICC <0.70 resulted in adjustments establishing that consensus was achieved. Conclusions: Undertaking this multi-step, cross-cultural adaptation procedure has effectively ensured that the 46-item Flodén ATODAI [North America version] produces valid and reliable measurements.

3 nurses' awareness, knowledge, skill and competence, i.e. role has an impact upon the organ donation and by that the organ transplantation process. The care by specialist nurses is the key to successful donor management in the critical-care (CC) setting since their actions and behavior are significantly associated with authorization to, or decline of, organ donation (OD) (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). In addition, ICU nurses' attitudes have an impact on the availability of organs for individuals who need life-saving organ transplant treatment (5,(8)(9).
No studies measuring attitudes toward organ donor advocacy (ATODA) in a clinical context existed before 2011. One reason for this is the absence of validated measuring instruments. In 2011, with the intent to gain an understanding of nurses' behavior, and their level of ability to advocate for their patients who are either potential or actual organ donors, Flodén et al. (13) developed the 51-item Swedish instrument "Attitudes Toward Organ Donor Advocacy Scale" (ATODAS) to measure ATODA among ICU and CC nurses. This instrument measures ATODA by describing nurses' actions while caring for potential organ donors and throughout the donation procedure and evaluates changes in organizational structure, guidelines, and educational interventions. The ATODAS is validated in the Swedish context by its application on more than 1,200 ICU nurses, i.e. >50% of all ICU nurses in Sweden. This ATODAS instrument is limited to the Swedish context since it only exists in the Swedish language. Today the ATODAS is to our knowledge the only established instrument within the context of measuring organ donor advocacy, and there is a need for a universal translation among different cultures and countries. Currently, the Flodén ATODAI [North American version] is in use in several countries and continents, and the process of developing a Spanish version has started.
Since specific behavior by ICU personnel is significantly associated with the frequency of referral and OD consent, it is of crucial importance to understand the reasons behind ODA. The concept of ODA in the situation of OD is defined by Flodén et al. (5) as respecting the potential or actual organ donor's rights, representing, or speaking up for his/her wishes, as well as the family's points of view, in the OD decision-making process. According to the International Council of Nurses' Code of Ethics, a nurse's primary professional responsibility is to people requiring nursing care. Thus, nurses' behavior and their level of ability to advocate for their patients' desires applies to potential and actual organ 4 donors (14). In regard to nurses' professional ethics in situations when the possibility of OD arises, nurses should represent and defend their patients' wishes regarding ODA (15). The relative rarity of OD in any hospital or country makes it important to reach out to an international clinical context to establish developmental changes, i.e. professional and/or organizational. After reviewing the roles and practices of ICU and CC nurses in North America, it became clear that the Swedish ATODAS needed to be adjusted to be used in North America (16). Therefore, the aim of this study was to translate, adapt, and establish the psychometric properties of the Swedish ATODAS to one which would be equally valid and reliable in North America. As part of the instrument development in this study, the name of the instrument changed from ATODAS, the 51-item Swedish scale, to Flodén ATODAI (Attitudes Toward Organ Donor Advocacy Instrument), the North American English version.

Design
The study used a methodological design comprising of a cross-cultural adaptation procedure to effectively translate the 51-item Swedish ATODAS instrument for use in other cultural and language settings. Specifically, the study considered Brislin's multi-step approach as best practice (18). An additional Delphi technique procedure was performed on the Flodén ATODAI [North American version] as a complementary adaptation approach to secure higher scientific certainty of the instrument with regard to validity and reliability by testing the items for content relevance, clarity, and domain coverage.

Description of the ATODAS [Swedish version]
Flodén et al. (13) developed the Swedish 51-item ATODAS as a means of psychometric evaluation of measuring ICU nurses' ATODA, including validation and reliability testing. In addition to the demographic data, the instrument contains three dimensions covering statements about attitudes toward: actions to safeguard the wishes of the potential organ donor; actions for supporting the family of the potential organ donor; and actions that promote OD at an organizational or structural level.

5
The procedure to transfer the Swedish ATODAS instrument into an international arena was guided by Brislin's (18) multi-step back-translation approach, complemented by a Delphi technique procedure ( Figure 1). The first step was for a professional and native American English-speaking interpreter and bilingual Swedish translator to translate the Swedish ATODAS instrument into American-English. The second step comprised of back-translation into American-English, as performed by another expert-a native Swedish-speaking bilingual translator. The translation was performed blindly, i.e. without access to the original version of the Swedish ATODAS.
Step three constituted cross-language testing by the international committee, consisting of three OD specialists; one representing Sweden (PI), and two representing the United States of America

Study Populations: Steps Four to Six
Step four: Seven designated ICU or CC nurses in the greater Los Angeles with experiential knowledge of caring for at least one organ donor formed an expert panel. The panel evaluated the content validity of the items, with reference to Lynn's criteria (17). All seven nurses on the panel were female, aged between 29-55 years with a mean age of 44.2 years, and their work experience in the ICU and/or Emergency Department ranged between 5-31 years. The panel represented nurses from trauma, education, and teaching hospitals: Three worked in the ICU; three in the Emergency Department; and one in the Education Department. Three of the experts were managers/charge nurses, one was a clinical nurse specialist, one a nurse educator, and two were bedside nurses.
Step five: In total, 50 ICU nurses from two hospitals in the greater Los Angeles area participated in the test and retest; one university-affiliated hospital (with different types of ICUs); and one county or community hospital (one ICU) ( Table 1). The inclusion criteria were: Being an ICU or CC nurse; experiential knowledge of caring for at least one organ donor; and currently working in a clinical setting with OD.
The exclusion criteria were: Being a nurse who was not currently working and/or being a nurse without experience of caring for organ donors.
Step six: A preselected panel of 15 nurses in the United States of America, with extensive experiential knowledge of caring for organ donors, comprised the Delphi panel for the purpose of completing the additional Delphi technique procedure ( Table 2).  (17,19).
Step four: First data analysis

Content Validity
The expert panel was formed to estimate the content validity (with reference to Lynn's criteria (17)  Step five: Second data collection The study performed a test-retest procedure to estimate stability (reliability testing) of the adjusted version of the prefinal 46-item version of the Flodén ATODAI [North American version], as developed from the data analysis performed in step four. Fifty ICU nurses agreed to participate by answering the instrument on two occasions, with two weeks in between.
Step five: Second data analysis

Test-Retest Reliability
The intraclass correlation coefficient (ICC) was used to measure the strength of agreement between the test and retest, using ordered categorial data (20). The level of agreement was confirmed via the weighted form of kappa coefficients (ҡ Weight ) (21).
Moreover, the sign test tested for whether systematical differences occur in either direction, described by exact agreement. The test was two-sided and conducted at the 0.05 significance level.
The ICC, the ҡ Weight , and the sign test analyses were performed using SAS software version 9.4 (SAS Institute Inc., Cary, NC, USA).

Homogeneity and Stability Reliability
Homogeneity reliability was estimated using Cronbach's alpha coefficient (α) via SPSS 18.0. According to the conventional rule by Nunnally, this coefficient should at least exceed 0.70 (22).
Step six: Third data collection Step six: Third data analysis After round I, this study's primary investigator (PI) summarized and analyzed all participants' recommendations. The Delphi panel rated all 22 items as either "relevant but needs minor alteration [3]", or "very relevant and succinct [4]". Four of the items were recommended to be kept as they were. The PI, in consultation with the co-investigators, adjusted and re-worded the remaining 18 items, guided by the Delphi panel members' recommendations. After round II, the PI, in consultation with the co-investigators, summarized, analyzed, and adjusted the Flodén ATODAI [North American version], again guided by the recommendations of the panel.

Content Validity
The first data collection comprised of the expert panel rating the prefinal version of the Flodén ATODAI [North American version]. The international committee then analyzed this data for CVI by calculating both the I-CVI and the S-CVI. The I-CVI ranged from 0.82 to 1.0, with a mean of 0.97, while the S-CVI averaged 0.97. This meant the CVI was >0.78 and, therefore, content validity was established beyond the 0.05 significance level, which is the required criterion according to Lynn (17) and Polit and Beck (19). This resulted in a reduction of the number of instrument items from 51 to 46.
Of the remaining 46 items, five were re-worded using the recommendations of the expert panel.

Test-Retest Reliability
The strength of agreement between the test and retest was calculated both by ICC and by ҡ Weight .
Also, the sign test was used to identify whether any systematical differences had occurred. None of the items showed statistically significant systematic changes. The retest values were systematically higher for most of the items. The ICC values were, as is to be expected, very similar to those of ҡ Weight (25).

Homogeneity and Stability Reliability
Homogeneity reliability was estimated using α for the 24 items identified with an ICC >0.70 was α =0.90. None of the items had a greater α coefficient "if item was deleted", meaning that none of the items would substantially affect reliability if they were removed. Furthermore, all items had a "corrected item-total correlation" of 0.

Discussion
The key to successful donor management in the CC setting is significantly associated with the ICU and CC nurses' attitudes toward OD, and by that will have an impact on the availability of organs for individuals who need life-saving organ transplant treatment (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Before 2011 no studies measuring ATODA existed in the worldwide clinical context. Which is why the Swedish 51-item ATODAS was developed and validated by Flodén et al. (13) and became the first instrument to measure ATODA among ICU and CC nurses. For a worldwide use the primary limitation of the ATODAS is linguistic since it is written in Swedish, but socio-cultural and legal limitations also exist (18,26). To address these limitations and allow the scale to be used in an international clinical context, a systematic translation procedure for cross-cultural adaptation was initiated and performed (18) (Figure 1).
The linguistic limitation was addressed by the international committee of experts as a validity check.
This cross-language testing was essential to ensure a high-quality translated instrument and to safeguard that the translated version reflected the same item content as the original version (18,27).
The content validity followed Lynn's recommendations on how to quantify an otherwise subjective 13 process (17). Ratings and written feedback by the expert panel was instrumental in making well-  (20,25). Therefore, the results concluded that reliability was established.
The homogeneity and stability reliability testing focused on the 24 items identified with an ICC >0.70, and the Cronbach's alpha established a reasonable degree of both stability and homogeneity with α =0.90 for the initial test, and 0.913 for the retest (22). For the tested 24 items, the Cronbach's alpha coefficients showed excellent homogeneity and stability reliability.
The Delphi technique procedure was performed as a complementary adaptation approach to secure higher scientific certainty of the instrument (23,28). Focus was on the remaining 22 items with ICC <0.70, where all of these items previously had been rated as "relevant and succinct" or "relevant but needed minor alteration" by the expert panel.

Consent for publication
Not applicable.

Availability of data and materials
The datasets used and/or analyses during the current study are available from the corresponding author on reasonable request.

Competing interests
The authors declare that they have no competing interests.

Funding
This independent research study was partially funded by a grant from The Swedish Transplant