F1000Research F1000Research 2046-1402 F1000 Research Limited London, UK 10.12688/f1000research.134195.1 Study Protocol Articles Cross-cultural adaptation and validation of the Greek version of the Kerlan-Jobe orthopaedic clinic shoulder and elbow score in Greek overhead athletes

[version 1; peer review: 2 approved]

 Paraskevopoulos Eleftherios Conceptualization Data Curation Formal Analysis Investigation Methodology Project Administration Resources Software Visualization Writing – Original Draft Preparation https://orcid.org/0000-0001-5552-5101 a 1 2 Plakoutsis George Data Curation Project Administration Resources Software Supervision Validation Writing – Review & Editing 2 Papandreou Maria Data Curation Formal Analysis Project Administration Resources Software Supervision Validation Writing – Review & Editing 2 Department of Physiotherapy, School of Health Sciences, Panepistemio Peloponnesou, Tripoli, Peloponnese, Greece Department of Physiotherapy, Panepistemio Dytikes Attikes, Egaleo, Athens, Greece e.paraskevopoulos@go.uop.gr

No competing interests were disclosed.

 15 5 2023 2023 12 498 9 5 2023 Copyright: © 2023 Paraskevopoulos E et al. 2023 This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Background: Overhead athletes frequently perform rapid and powerful throwing overhead strokes in positions at the extreme range of motion, increasing the risk of upper limb injury. The Kerlan-Jobe Orthopedic Clinic (KJOC) Shoulder and Elbow Score has shown to be a valid and reliable questionnaire that can be used for the assessment of the functional status of the upper limb of patients involved in highly demanding overhead sports. The KJOC has been translated into several other languages however, a Greek version of the KJOC is not available yet.

Methods: The KJOC will be cross-culturally adapted into Greek following international guidelines. At least 100 overhead athletes with or without shoulder or elbow complaints will be recruited and asked to fill in the Greek version of the KJOC twice and the Disabilities of Arm, Shoulder and Hand Questionnaire (DASH) once. The internal consistency and the test-retest reliability will be examined using Cronbach’s alpha and the intraclass correlation coefficient (ICC), respectively. The standard error of measurement (SEM) and the minimum detectable change (MDC) will be calculated and possible ground or ceiling effects will be also examined. Convergent validity will be evaluated with the Greek DASH using Pearson’s correlation.

Results: The results of this study will be presented in an article to be published later.

Conclusions: This report describes the process of translation and cross cultural adaptation of the Greek version of the KJOC. We believe a study protocol will assist researchers in the field to improve the reporting of similar studies and as a result improve the quality of their studies.

 Overhead athlete questionnaire patient-reported outcome elbow shoulder Kerlan-Jobe Orthopedic Clinic The author(s) declared that no grants were involved in supporting this work. Introduction

It is well known that overhead athletes frequently perform rapid and powerful throwing strokes above head-height during ball serving, in positions at the extreme range of motion, increasing the risk of shoulder or other upper limb injury ( Paraskevopoulos et al., 2021a, 2021b, 2023). Nevertheless, the increased physical demands placed at the shoulder and elbow in overhead athletes may also affect physical performance during play ( Clarsen et al., 2015). Despite the presence of symptomatology in this population, research has shown that they continue to train and compete irrespective of clinical symptom severity ( Agresta et al., 2019; Clarsen & Bahr, 2014). Experts in the field support that prevention is key in the management of overhead athletes, including evaluation and monitoring of upper limb health and performance ( Cools et al., 2015; Sukanen et al., 2022). Patient-reported outcome measures (PROM) are highly suggested in this clinical population for the assessment of functional performance ( Paraskevopoulos et al., 2023).

The Kerlan-Jobe Orthopedic Clinic (KJOC) Shoulder and Elbow Score has shown to be a valid and reliable PROM that can be used specifically in overhead athletes ( Alberta et al., 2010; Merolla et al., 2018). The KJOC was designed by Alberta et al. (2010) for the assessment of the functional status of the upper limb of patients involved in highly demanding overhead sports. The KJOC includes questions related to self-perceived ability to perform sport-specific movements such as, hitting a ball. The KJOC has been designed not only for symptomatic athletes but also for the assessment of the functional performance of healthy athletes as well ( Sukanen et al., 2022). Lastly, the KJOC can also be used in order to examine the effectiveness of any intervention in overhead athletes with shoulder or elbow pathology ( Sukanen et al., 2022).

The original version of the KJOC has been translated from English into several other languages, including Korean ( Oh et al., 2017), Finish ( Sukanen et al., 2022), Italian ( Merolla et al., 2017), Turkish ( Turgut & Tunay, 2018), Norwegian ( Fredriksen & Myklebust, 2019) and German ( Schulz et al., 2022). To date no comparable PROM exists in the Greek language, although overhead sports are highly popular in Greece. Thus, the aim of this study is to translate and cross culturally adapt the KJOC in Greek-speaking overhead athletes and examine the reliability and validity of the Greek version of the KJOC in this population.

 Protocol

The authors will collect data from multiple outpatient private clinics in Greece. To be eligible to participate in the study patients should meet the following criteria: 1) be adults (aged >18 years), 2) to compete and train at least two times weekly in an overhead sport, such as handball, volleyball, baseball, softball, basketball, water polo, tennis, or badminton and 3) to be able to natively communicate, read and write in Greek. Healthy and injured players with shoulder or elbow complaints will be included. Athletes will be excluded if they suffer from cognitive, communication, or psychological issues. Also, athletes suffering from neurological dysfunction or cardiovascular or pulmonary dysfunctions that result in functional limitations will be excluded. All participants will sign an informed consent form before participation. The study protocol has been approved by the ethics committee of the University of Peloponnese.

Sample size

A minimum sample of 100 participants will be considered adequate for the assessment of the internal consistency, floor and ceiling effects, construct validity, test-retest reliability, and measurement error based on the recommendation of the consensus-based standards for the selection of health measurement instruments (COSMIN) ( Terwee et al., 2012).

 Translation and cross-cultural adaptation

The procedures for translation and cross-cultural adaptation of the KJOC will be based on previously reported studies ( Beaton et al., 2000; Schulz et al., 2022). The first step includes the forward translation of the English version into Greek by two independent bilingual translators who are Greek in origin. One of the two forward translators is a Lecturer in physiotherapy with more than 30 years of experience in clinical physiotherapy and academic teaching. The other forward translator will have no physiotherapy or medical background and will be unaware of the existence of the KJOC. The two forward translators will compare their translations until a consensus is reached. A single Greek version of the scale will be formed from the two reports and the comments of the two translators. Again, another two bilingual independent translators will complete the two backward translations of the Greek version of the KJOC into English. The backward translators will compare the scale with the translated version in order to confirm whether the semantic, conceptual, and experimental equivalence are met.

The pre-final Greek version of the KJOC will be then pilot tested in 10 overhead athletes. From these 10 athletes, five will be symptomatic and five will be asymptomatic in the shoulder or elbow region. After completion of the 10 pilot pre-final versions of the KJOC an interview will be followed individually with all 10 athletes. Two physiotherapists with more than 10 years of experience will conduct the interviews. In each individual interview the participants will be asked to explain if the content of the pre final version of the scale is clear after reading the instructions, the items and responses. Furthermore, they will be asked to clarify whether parts of the scale are not clear and will provide suggestions for any possible modifications that may improve clarity.

 Reliability

Test-retest reliability will be examined in the final Greek Version of the KJOC (Gr-KJOC). All participants (n=100) will be asked to complete the Gr-KJOC twice. The first time that they will complete the Gr-KJOC will be during their first contact with the authors and the second will be three to five days later. The interval of test-retest sessions in this study is specified in order to minimize recall and to be suitably short to guarantee clinical stability between testing sessions ( Aljathlani et al., 2022). The clinical stability of the participants will be examined by asking each one whether they believed that their symptoms were the same in the retest session ( Bennell et al., 2000). Only patients that answer that their symptoms are the same in the retest session will complete the Gr-KJOC for a second time. Completion of the Gr-KJOC twice should allow the investigators to examine test-retest reliability by comparing the results of the test and retest sessions. Internal consistency will be also assessed based on the degree to which separate items of the Gr-KJOC relate to each other ( English & Keeley, 2014).

 Validity

The construct validity will be examined after correlating the results of the Gr-KJOC with the Greek Version of the Disability of the Arm, Shoulder, and Hand (DASH) and the DASH Sports Module (DASH-SM) ( Aljathlani et al., 2022). The Greek DASH has shown to be a reliable and valid instrument that can provide a standardized measure of patient-centred outcomes in Greek-speaking patients with upper limb disorders while the DASH-SM assesses symptoms and the functional status of the upper limb in sports settings ( Themistocleous et al., 2006). The DASH contains 30 questions; 21 related to function, six related to symptom severity and three to social function. Each question is rated on a 5-point scale (1, no difficulty; 2, mild difficulty; 3, moderate difficulty; 4, severe difficulty; 5, unable). The questionnaire score is calculated by applying established formulas for the first 30 questions and the scores range from 0 (the best) to 100 (the worst) ( Themistocleous et al., 2006). The DASH-SM contains four questions and the goal of the DASH-SM is to identify the specific difficulties that athletes might experience but which may not affect their activities of daily living and consequently may go “undetected” in the 30-item portion of the DASH ( Aljathlani et al., 2022).

 Feasibility

The mean duration for reading and completing the questionnaire by the athletes will be measured. Also, the duration needed for analysing the results of the questionnaire by one of the investigators and calculating the final score will be also measured. Questionnaire analysis will be conducted by one investigator in all cases.

 Floor and ceiling effect

Verification of floor and ceiling effect will be made by percentage (>15%) of the participants who have obtained the minimum and maximum scores in the Gr-KJOC, respectively ( Terwee et al., 2007).

 Statistical analysis

All data will be analysed using IBM SPSS statistics (RRID:SCR_016479) 28.0. Descriptive statistics will be calculated and reported for all measures. The statistical level of significance will be set at p < 0.05. Normal distribution of the data will be examined via the Shapiro-Wilk test. Parametric tests will be selected for data with normal distribution and non-parametric tests will be selected for data without normal distribution.

Internal consistency

Internal consistency, as a degree of homogeneity of the single items of the Gr-KJOC, will be examined using Cronbach’s alpha. Internal consistency will be considered acceptable for the Gr-KJOC if the alpha value is going to be within the recommended range of 0.70 to 0.95 ( Aljathlani et al., 2022; Prinsen et al., 2018).

Test re-test reliability (measurement errors)

The Intraclass Correlation Coefficient (ICC) for absolute agreement will be used to examine test re-test reliability of each item and the total score of the Gr-KJOC. Measurement errors from the use of Gr-KJOC will be estimated from the Standard Error of Measurement (SEM) and the Minimum Detectable Change (MDC). For the SEM the following equation will be used: SEM = SD√(1-ICC). SD will be the pooled SD calculated by the following equation: SDpooled = √(SD1 2 + SD2 2)/2. Then, the MDC will be calculated using the following equation: MDC= SEM × 1.64 × √ 2 reflecting the smallest detectable within-person change in score ( Aljathlani et al., 2022; Portney & Watkins, 2009; Valentín-Mazarracin et al., 2021).

Construct validity

Construct validity of the Gr-KJOC will be examined by correlating the results of the Gr-KJOC with the DASH and the DASH-SM. Spearman’s correlation will be used to examine construct validity. Correlation coefficients of 0.70-0.89, 0.40-0.69 and 0.10-0.39 will be considered as strong, moderate and weak, respectively ( Schober et al., 2018).

The known group method analysis will also be used to assess a further aspect of construct validity and identify whether the Gr-KJOC can actually differentiate between symptomatic (playing with arm symptoms or unable to play due to arm symptoms) and asymptomatic athletes (playing without any arm symptoms), as previously performed ( Schulz et al., 2022). In order to establish evidence of known-group validity, independent samples t-test and Mann–Whitney U test will be used. Also, Pearson’s effect size r will be calculated.

 Conclusions

This study will translate and culturally adapt the original KJOC scale into Greek for the first time using a standardized approach. We aim to show that the Greek version of the KJOC will be reliable and valid to use for the assessment of the functional capacity of healthy and injured overhead athletes in the should or elbow. Our aim through this research process will be to develop a translated KJOC that will be used by researchers and health care professionals, as well as coaches in Greek-speaking athletic settings for assessing functional status, treatment outcome and return-to-sport ability in this population. Lastly, the KJOC can also be used to predict shoulder or elbow injuries since there is evidence to show that there is a relationship between lower KJOC scores and future in-season injuries for overhead athletes ( Holtz & O’Connor, 2018).

Ethics

The study protocol was approved by the Institutional Ethics Committee of the University of Peloponnese (Ref No. 7365).

 Study status

The study has started. The study has not been completed and no data analysis has been performed.

 Data availability

No data are associated with this article.

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Competing interests: No competing interests were disclosed.

 5 8 2024 Copyright: © 2024 Sukanen M 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation approve

The authors report a study protocol about cross-cultural adaptation and validation process of the Kerlan-Jobe orthopaedic clinic shoulder and elbow score in Greek language. The protocol shows the efforts the authors have made with planning the research according to accepted standards. The protocol is mostly very clearly presented and below I have listed some minor comments and recommendations for the author’s consideration.

In the abstract (methods), I would replace the term ground with floor, as later on in the manuscript you refer to floor effect.

In the abstract (conclusions), I recommend adding that this protocol also describes the assessment of psychometric properties of the Greek KJOC in addition to cross-cultural adaptation process.

Many of the keywords are included in the study title, perhaps I would consider replacing e.g., shoulder, elbow and KJOC for example with psychometric properties and reliability.

In the introduction you can add that KJOC has also been validated into Spanish language. Please also note that Finnish is written with two n’s.

In the end of introduction, I would rephrase the study aim more precisely to match this study protocol.

Under the subheading “Sample size”, it is perhaps not necessary to introduce the abbreviation COSMIN.

Under the subheading “Translation and cross-cultural adaptation”, did only the translators work through the adaptation process of the Greek KJOC? Many times, multidisciplinary team input is of great value during cross-cultural adaptation.

Under “Reliability” I would suggest extending the test-retest time interval closer to a week.

In general, regarding the so far reported measurement properties of KJOC, the authors could briefly conclude what kind of validity/reliability results previous studies have obtained for the same variables you report that will be tested for the Greek KJOC.

Under "validity", the authors provide general information regarding DASH as a comparison score, but this information is lacking for KJOC. I would recommend the authors to add a description of KJOC as well.

Under “validity”, it is a great advantage that the authors have the possibility to use a translated and validated questionnaire as a comparison score to test validity.

I would recommend the authors to follow the same order while describing measurement properties throughout the manuscript (abstract, data collection, analysis) e.g., starting with internal consistency, followed by validity, reliability, floor- and ceiling effect etc. This would make the storyline more logical for the reader.

I would also add information of obtaining permission to move forward with the study from the original developer of the KJOC score.

Is the study design appropriate for the research question?

Yes

Is the rationale for, and objectives of, the study clearly described?

Partly

Are sufficient details of the methods provided to allow replication by others?

Yes

Are the datasets clearly presented in a useable and accessible format?

Not applicable

Reviewer Expertise:

My area of research lies between sport and health sciences with a background in physiotherapy. I have expertise in conducting cross-cultural adaptation and validation research of patient-reported outcomes from a previous publication and current studies.

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

 10.5256/f1000research.147227.r263359 Reviewer response for version 1 Fayão Julia 1 Referee University of Sao Paulo Ribeirão Preto Medical School, Sao Paulo, Brazil

Competing interests: No competing interests were disclosed.

 22 5 2024 Copyright: © 2024 Fayão J 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation approve

I recommend extending the reliability testing time to up to seven days instead of five

I suggest conducting responsiveness testing.

It is important to mention whether there was authorization from the original author for the translation and validation.

I recommend providing more information about the questionnaire that will be translated and validated into Greek.

I suggest including "study protocol" in the title.

As for my thoughts on the article, I would like to highlight its relevance in the context of cultural adaptation and validation of questionnaires for Greek high-performance athletes. This type of study is crucial to ensure the accuracy and reliability of measurements across different cultures and athletic contexts. Organizing my comments into 'Major' and 'Minor' points, I would like to address methodology, clinical relevance, and suggestions for improvement:

Major:

The methodology used for translation and validation is essential to ensure conceptual and linguistic equivalence of the questionnaire.

The clinical relevance of this study lies in the need for specific assessment tools for Greek athletes due to the unique demands of their sports.

The study has the potential to positively impact clinical practice and research in sports medicine by providing a validated and culturally adapted assessment tool.

Minor:

It would be helpful to provide more details on the specific methods used in translating and validating the questionnaire.

A discussion of the study limitations and possible areas for future research would be valuable to contextualize the results.

Thank you again for the opportunity to review this study.

Is the study design appropriate for the research question?

Yes

Is the rationale for, and objectives of, the study clearly described?

Yes

Are sufficient details of the methods provided to allow replication by others?

Yes

Are the datasets clearly presented in a useable and accessible format?

Yes

Reviewer Expertise:

My doctoral research consists of an assessment of the shoulder complex in volleyball athletes

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.