Introduction
Oral presentations are widely used for assessing student performance in higher education settings [1]. They are a crucial tool for evaluating students’ grasp of a subject [2]. A well-prepared and effectively delivered speech can impart new information to the audience and clarify and structure complex ideas and thought patterns [3]. Competence in oral presentations requires knowledge, skill, and the right attitude to speak in public to inform, express oneself, communicate, and persuade others [4]. This skill must be learned and practiced consistently [5]. Recent studies have emphasized the importance of effective oral presentation skills for nursing students and professionals, as these skills are crucial for communicating with healthcare teams, patients, and families [2, 4]. The importance of oral presentations spans various academic disciplines, including medicine, nursing, engineering, health, business, and communication [6], as professionals in these fields need to communicate with colleagues in meetings, seminars, and conferences [7].
Education experts argue that students often enter the job market with notable deficiencies in oral communication skills and frequently need help with public speaking [8]. Proficiency in oral presentation is crucial for effectively conveying ideas to others, especially within the nursing profession [9], as it offers nurses a strong foundation for future career success [10]. Research indicates that oral presentation of information in nursing is more impactful and valuable than written presentation [11].
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Oral presentation skills are crucial for effective communication and transfer of patient care responsibilities among nurses. Short presentations form the basis of collaborative work in hospitals [12]. A study of care standards in 14 hospitals with high mortality rates in the United Kingdom revealed subpar nursing delivery in some facilities [13]. According to Collins (2014), nurses sometimes struggle with structuring and presenting information, and these challenges are attributed to both the nature of nursing delivery and general presentation skills [14]. In modern nursing, there is a growing emphasis on nurses taking on diverse roles in prescribing and justifying treatments, particularly consultant nurses and clinical nursing specialists who are expected to participate in multidisciplinary meetings. Proficiency in oral presentation skills is valuable for these meetings [15].
Effective presentation skills can be acquired through learning and are not determined by genetics [9]. Texts related to oral presentation often focus on assessing and providing feedback from self, peers, and teachers, which can have significant outcomes [4, 16]. However, the evaluation and feedback topics for oral presentation skills often need to be more specific to be helpful, leading to students having an indifferent attitude toward feedback due to its ambiguous and non-constructive nature [17].
Using a standardized assessment tool with subject-specific criteria can help identify expected competencies and pinpoint areas needing improvement after assessment [7]. Clear evaluation criteria can prevent subjective bias and ensure fair evaluation [8]. Evaluators must provide clear instructions for student evaluation and standardized criteria for assessment and feedback to address the quality of work in the course [18]. Many disciplines are adopting new, valid evaluation tools specific to their field. Practical design, understanding, and appropriate use of assessment tools are crucial for different assessment methods [19, 20]. Subjective assessment of oral presentations may lead to inaccurate evaluation of student learning [2].
On the other hand, the ability for objective self-evaluation is linked to metacognitive skills [21], and tools for evaluating public speaking performance are essential for enhancing students’ oral presentation skills [22]. A reliable and valid tool for objectively assessing oral presentations made by nursing educators and peers is necessary. Studies suggest that peers have a more significant impact on evaluating each other’s presentations than teachers. Comprehensive tools for measuring oral presentation performance can significantly enhance oral presentation skills [2, 21].
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Based on the literature review, various tools are available for evaluating oral presentations. For instance, Tsang’s research includes 40 items and assesses factors such as voice, facial expressions, enthusiasm, and time management in oral presentations [17]. Another evaluation tool developed by Degriz et al. focuses on content (including the quality of the introduction, structure, and conclusion), expression (which entails eye contact, vocal delivery, enthusiasm, audience interaction, and body language), and overall quality [23]. However, objectively assessing these overlapping tools presents challenges, as they were created without rigorous validity and reliability testing. The Oral Presentation Evaluation Scale (OPES), developed by Chiang et al. [2], is a 15-item instrument that evaluates three essential components: content quality, communication effectiveness, and speech clarity [2].
Nurses provide patient care and communicate medical information to other healthcare teams, families, and patients. It is important to include training in speaking skills for nursing students as part of the curriculum and to evaluate their progress using appropriate tools [24]. Chiang et al. developed an oral presentation evaluation scale for nursing students, which assesses three components: quality and accuracy of content, effective communication, and speech clarity [2].
Translating the assessment tool and ensuring its validity and reliability for Iranian nursing students cannot be overstated, especially in light of potential cultural and educational variations. The assessment tool has been meticulously crafted to assist nursing students in recognizing their strengths and areas requiring development in oral presentation skills. A Persian version of this assessment tool does not exist, and it has been custom-made for student use. Therefore, the primary objective of the present research is to translate the oral presentation skills assessment scale into Persian and thoroughly investigate its psychometric properties, including factor structure, reliability, and validity, within the context of Iranian nursing students.
Methods
Design and setting
The methodological design aimed to translate the OPES into Persian and assess the psychometric properties of the Persian version among Iranian nursing students in 2023.
Participants
In our research, we selected nursing students from a university in Ardabil province, Iran, based on specific criteria. The criteria included being full-time nursing students in their sophomore, junior, or senior years and providing informed consent. We did not include first-year nursing students in the study. We determined the sample size based on recommendations for factor analysis, which suggest having a minimum of 3–10 participants per item on the assessment scale [25]. The “Oral Presentation Skills Assessment Scale” contains 15 items, so the minimum required sample size was between 75 and 150 participants. We aimed to recruit all 474 eligible nursing students from the university to account for potential dropouts or incomplete responses. On the scheduled day for data collection, all 474 eligible nursing students who met the inclusion criteria received a packet containing a demographic questionnaire, a consent form, and the OPES instrument. Each packet was labeled with a unique identification number to ensure the confidentiality of the data.
Data collection
The data collection process included demographic characteristics form and the Oral Presentation Evaluation Scale (OPES) designed for nursing students.
Instruments
Demographic characteristics form
The demographic characteristics survey gathered data on nursing students, encompassing their age, gender, marital status, semester, language, previous experience with oral presentations, training backgrounds, and reading habits.
Oral presentation evaluation scale (OPES)
Chiang et al. developed and validated the OPES for nursing students through a two-phase study [2]. In Phase I, they employed deductive and inductive approaches to create a 26-item scale that addressed content accuracy, effective communication, and speech clarity. Phase II included recruiting 650 nursing students for exploratory and confirmatory factor analyses, leading to a final model consisting of 15 items across three factors. The OPES demonstrated robust reliability and validity, establishing it as a significant tool for evaluating nursing students’ oral presentation skills. This scale comprises 15 items categorized into three sections: Accuracy of Content, Effective Communication, and Speech Clarity. A 5-point Likert scale was utilized in all instances, ranging from Never (indicating the behavior was not displayed or performed before, with a probability of less than 10% (0–10%)) to Always (suggesting the behavior was exhibited almost consistently, with a probability of about 90% (81–100%) [2]. The other three options on the scale include Occasionally (11–30% chance), Sometimes (31–60% chance), and Often (61–80% chance). Higher scores reflect improved performance [2].
Psychometric testing
Translation procedure
The oral presentation evaluation scale underwent a rigorous translation process in accordance with the guidelines set by the World Health Organization (WHO) [26]. To begin, permission was obtained from the manufacturer to translate the English version into Persian. This translation was carried out using the forward-backward method by two professionals who were not only fluent in English but also had extensive experience in translating medical texts and were well-acquainted with the questionnaire’s content. The translations were then meticulously compared, with each question being thoroughly analyzed for its intended meaning and concept. This meticulous comparison process ensured the selection of the most appropriate options to craft a comprehensive and accurate Persian version of the instrument.
In the subsequent stage, the Persian translation underwent a back translation process, where two translators proficient in both Persian and English and adequately knowledgeable about the OPES translated the Persian version back into English. The resulting English translation was then sent to the principal designer for final approval. It was crucial that the English version aligned with the original version in terms of concept and intent, and after thorough scrutiny, it received the necessary approval. Consequently, the final English version of the instrument was crafted and made available in Persian.
Validity and reliability process
Face and content validity
The study’s accuracy was evaluated using the cognitive interview method. In this stage, 15 nursing students were asked to review each item, assess the wording’s clarity, simplicity, and comprehensibility, and notify the researcher about any problematic items or words. The researcher made necessary adjustments to enhance the overall quality of the study, explaining the concept of the items that were flagged as complex and replacing simpler words based on their suggestions.
The content validity index is used to determine the study’s content validity. In this research, 15 expert nursing educators evaluated the content validity ratio of each questionnaire item regarding cultural relevancy [27]. They rated them on a scale of four: completely relevant, relevant, somewhat appropriate, and unrelated. If any item scored more than 0.79, it was retained in the questionnaire. If the CVI score was between 0.70 and 0.79, the phrase was deemed questionable and required revision. If it was less than 0.70, the word was unacceptable and had to be removed [28]. At this stage, the formula used for the Content Validity Index (CVI) was: CVI = (Number of experts who scored 3 or 4 related questions) / Total number of experts.
Construct validity
The study aimed to investigate the validity of a questionnaire using exploratory and confirmatory factor analyses. For the validity assessment, the researchers needed at least 3 to 10 participants for each item in the questionnaire [29]. In this case, 200 nursing students participated in the exploratory factor analysis, and 275 nursing students participated in the confirmatory factor analysis.
To ensure the adequacy of the sample, the researchers used the Kaiser-Meyer-Olkin (KMO) test and Bartlett’s sphericity test. The KMO index was found to be 0.875, which is acceptable since any KMO value higher than 0.5 is acceptable [30, 31]. Bartlett’s test was significant (P < 0.001), indicating that the data set was suitable for factor analysis. The exploratory factor analysis used principal component analysis followed by Promax rotation. Eigenvalues and factor loadings were considered higher than 1 and 0.3, respectively [32].
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Finally, the researchers used confirmatory factor analysis to validate the questionnaire’s dimensions and the proposed exploratory factor analysis model. They assessed the model fit using different fit indices belonging to three general categories: absolute fit (root means a square error of approximation (RMSEA), standardized root means square residual (SRMR), Goodness-of-Fit index (GFI), and chi-square), comparative fit (index (CFI), incremental fit index (IFI), relative fit index (RFI), normed fit index (NFI), and Tucker-Lewis index (TLI)), and affordable fit (parsimony comparative appropriate index (PCFI), parsimony normal fit index (PNFI), adjusted goodness-of-fit index (AGFI), and Akaike’s information criterion (AIC) [33].
Reliability
Two methods were utilized to check the scale’s reliability: internal consistency and test-retest. Cronbach’s alpha coefficient was calculated to evaluate internal consistency. The test-retest method assessed temporal consistency by administering the scale to 20 nursing students over two weeks.
Data analysis
When presenting descriptive statistics, the quantitative variables were expressed as the mean value and the standard deviation (SD), measuring the variability around the mean. Meanwhile, the qualitative variables were represented as frequency distributions and respective percentages. All data analyses were conducted using the SPSS statistical software, version 28, a widely used tool for statistical analysis and data management. Additionally, Lisrel 8.8, another statistical software, was utilized for specific types of studies or modeling. In determining statistical significance, a p-value of less than 0.05 was adopted as the threshold, indicating the level at which results were unlikely due to random variability alone. This standard choice of 0.05 provides a widely accepted guideline for establishing statistical significance in analyses.
We used a p-value of less than 0.05 as the threshold to determine statistical significance, indicating that results were unlikely due to random variability alone. We also employed the Differential Item Function (DIF) method, a statistical technique used in psychometrics, to systematically investigate potential gender bias within our analysis. This method allowed us to identify and account for variations in item performance between male and female respondents. Our rigorous approach helped ensure the integrity of our results, eradicating any inadvertent gender-related biases and leading to a more precise and unbiased representation of the underlying trends in our data analysis. The Convergent validity (CR) values for all factors exceeded the thresholds of 0.7 and 0.5, indicating convergent validity, suggesting that the factors consistently and reliably measure the same underlying construct.
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Results
The study included 474 nursing students, of which 200 participated in exploratory factor analysis and 274 in confirmatory factor analysis. Please refer to Table 1 for more information.
Table 1
The characteristics of participants
Variables | Description | Exploratory 200 | Confirmatory 274 | ||
|---|---|---|---|---|---|
N | % | N | % | ||
Age | - | 23.43 ± 3.99 | 23.08 ± 2.63 | ||
Gender | female | 105 | 52.5 | 144 | 52.6 |
male | 95 | 47.5 | 130 | 47.4 | |
Marital status | single | 161 | 80.5 | 221 | 80.7 |
married | 37 | 18.5 | 51 | 18.6 | |
Divorce/widowed | 2 | 1 | 2 | 0.7 | |
Semester | 3 | 54 | 27 | 51 | 18.6 |
4 | 39 | 19.5 | 54 | 19.7 | |
5 | 16 | 8 | 35 | 12.8 | |
6 | 36 | 18 | 61 | 23.7 | |
7 | 25 | 12.5 | 38 | 13.9 | |
8 | 30 | 15 | 35 | 12.8 | |
Language | Azeri | 183 | 91.5 | 250 | 91.2 |
Farsi | 17 | 8.5 | 24 | 8.8 | |
History of oral presentation | 1–2 | 17 | 8.5 | 257 | 93.8 |
More than 2 | 183 | 91.5 | 17 | 6.2 | |
History of oral presentation training | Yes | 46 | 23 | 69 | 25.2 |
No | 154 | 77 | 205 | 74.8 | |
History of reading eloquence books | Yes | 52 | 26 | 65 | 23.7 |
No | 148 | 74 | 209 | 76.3 | |
The questionnaire items were kept simple during the face validity assessment. To confirm the validity of the qualitative content, the opinions of 15 nursing students were gathered, and the phrasing of the questions was slightly modified based on their feedback. The content validity index (CVI) was more significant than 0.79 for all items, with an average scale CVI of 0.94. Moreover, the content validity index for all items ranged from 0.8 to 1.0, indicating that the questionnaire items were highly relevant and appropriate for the study.
The Kaiser-Meyer-Olkin value was 0.875, and Bartlett’s sphericity test showed a significant difference (χ2 = 203.26, df = 87, p < 0.0001). As a result, the data were suitable for factor analysis. Using Promax rotation, PCA extracted three factors. The eigenvalue and explained variance of the three factors were Factor 1, 5.414 (36.091%), Factor 2, 1.526 (10.173%), and Factor 3, 1.187 (7.915%), respectively. Together, these three factors accounted for 54.179% of the total variance. Based on the original instrument, these three factors were named accuracy of content factor 1, effective communication factor 2, and clarity of speech factor 3. The results of PCA are shown in Table 2; Fig. 1.
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Table 2
Principle components analysis with promax rotation factor loadings of OPES (n = 200)
Item/factor | F1 | F2 | F3 |
|---|---|---|---|
1.The content of the presentation corresponds to the topic. | 0.667 | - | - |
2. Presentation aids (such as PPT, posters, etc.) highlight the key points of the report. | 0.592 | - | - |
3. The presentation content is clear and focused. | 0.813 | - | - |
4. The presentation content is organized and logical. | 0.762 | - | - |
5. Presentation content follows rules and allows for proper timing and order. | 0.412 | - | - |
6. The content of presentation provides correct information. | 0.686 | - | - |
7. S/he is familiar with all the contents of the presentation. | 0.501 | - | - |
8. Confidence and enthusiasm are displayed appropriately. | - | 0.494 | - |
9. Body language is used appropriately to increase audience interest and learning. | - | 0.734 | - |
10. Interaction with the audience includes the use of eye contact and question and answer sessions. | - | 0.741 | - |
11. Audience questions are answered appropriately. | - | 0.655 | - |
12. The content of the presentation is brilliant and can arouse the interest and enthusiasm of the audience. | - | 0.657 | - |
13. The pronunciation of presentation is correct. | - | - | 0.715 |
14. The tone and volume of the presentation is appropriate. | - | - | 0.762 |
15. The words and expressions of the presenter are smooth and fluent. | - | - | 0.750 |
Eigenvalue | 5.414 | 1.526 | 1.187 |
Percentiles of variance, % | 36.091 | 10.173 | 7.915 |
Total variance, % | 54.179 | ||
Fig. 1
The standardized estimates of CFA model for validation sample
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The Differential Item Function (DIF) analysis found that the gender variable had a significant effect only in Step 1, specifically for the variable OPES clarity. In Step 1, the coefficient was calculated as 5.522 with a p-value of 0.000, indicating a substantial difference in OPES clarity between males and females. However, the subsequent analysis showed that both OPES clarity and OPES effectiveness did not exhibit significant differences between males and females. Therefore, while there was a notable difference in OPES clarity between males and females in Step 1, this difference became statistically insignificant in the subsequent analysis steps (Table 3).
Table 3
Differential item function test results for gender variable in OPES clarity, accuracy, and effective items
Step | Variable | Coefficient | Standard Error | t-value | p-value | Sig. |
|---|---|---|---|---|---|---|
1 | OPES Clarity | 5.522 | 0.000 | 1.000 | 286.588 | 0.000 |
1 | OPES Accuracy | 0.160 | 0.122 | 1.727 | 0.189 | 0.173 |
1 | OPES Effective | 0.221 | 0.124 | 3.183 | 0.074 | 0.247 |
2a | OPES Clarity | -0.009 | 0.037 | 0.060 | 0.807 | 0.991 |
2a | OPES Effective | -0.011 | 0.043 | 0.062 | 0.803 | 0.989 |
3a | OPES Effective | -0.016 | 0.037 | 0.197 | 0.657 | 0.984 |
4a | Constant | -0.102 | 0.121 | 0.715 | 0.398 | 0.903 |
The high CR values for the first two factors (0.928 and 0.843) indicate that these factors have good convergent validity, meaning that the items within each factor are strongly related and measure the same underlying construct. The lower CR value for the third factor (0.736) suggests that this factor has weaker convergent validity (Table 4).
Table 4
Convergent validity analysis
Construct | CR |
|---|---|
OPES Accuracy | 0.928 |
OPES Effective | 0.843 |
OPES Clarity | 0.736 |
The data was analyzed to test the fitness of the three-factor model. The results of the analysis indicated that the model fits the data well. The chi-squared test (x2 = 203.26 and p = 0.00) and other fit measures (RMSEA: 0.070; NFI: 0.94; CFI: 0.96; IFI:0.96; RFI: 0.92; AGFI: 0.88; NNFI: 0.95; PNFI: 0.78; standardized RMR: 0.06) showed that the three-factor model extracted from EFA had a good fit for the data. The results also showed that the CFA based on the three-factor model removed from EFA fit well with the obtained data, as shown in Fig. 1.
A test-retest method was used to assess the questionnaire’s reliability. The results indicated high stability and reliability, with a total stability reliability of 0.965. Additionally, individual factors such as accuracy of content, effective communication, and speech clarity also demonstrated high stability reliability, with ICC scores of 0.995, 0.922, and 0.965, respectively. Cronbach’s alpha coefficient was used to evaluate the internal consistency, which showed good internal consistency for the questionnaire, with a total internal consistency of 0.875.
Furthermore, the factors of content accuracy, effective communication, and speech clarity also demonstrated good internal consistency, with alpha coefficients of 0.803, 0.774, and 0.734, respectively. However, only three factors could be identified based on the parallel analysis results. This determination was made as these specific factors exhibited initial eigenvalues greater than the random values obtained in the parallel analysis.
Discussion
Using valid and reliable instruments in any research is crucial, as they can either validate or question the findings [34]. This study, unique in its focus on the Persian version of the OPES, aimed to translate and determine its psychometric properties in Iran. The lack of such tools to measure the competency of oral presentation skills among Iranian nursing students underscored the need to translate, cross-culturally adapt, and validate the OPES.
The results of the translation phase in this research suggested the acceptability of translating the original scale into Persian. However, different cross-cultural adaptation guidelines and forward and backward translations have been used in this study [35]. Instead of developing new tools, translation and cultural adaptation of existing tools can extract comparable data using valid questionnaires and facilitate information exchange among the scientific community [36].
After translating the questionnaire, it is essential to check if it is valid and reliable for the target population. Face validity is a crucial aspect of the validity analysis. This means the questionnaire should be easy to understand for the specific population it is designed for. In a study, nursing students could comprehend all the items in the Persian version of the scale, indicating good face validity [37]. When evaluating face validity, the nursing students learned all the items in the Persian version of the scale.
The findings indicated that the scale’s CVI was deemed acceptable, and no significant alterations were made to its face validity. In this study, 15 experts evaluated the content validity, and the items were revised based on their suggestions. The assessment of clarity and content equivalence confirmed the conceptual, semantic, and content equivalency and the sentence structure used in the translated version [38].
The results of factor analysis were 15 items that were placed in three dimensions, accounting for 54.179% of the total variance. To label the three dimensions proposed by factor analysis, the original scale, as well as the meaning of the items of each dimension alone and about other items, were considered; subsequently, the three factors were classified as: “accuracy of content,” “effective communication” and “clarity of speech” [2]. The confirmatory factor analysis results also presented those values of the fit indices indicating the acceptable fit of the proposed data model.
As it applies to oral presentations for nursing students, the accuracy of content is essential for communicating information involving health care education for patients and communicating with team members providing medical care in a clinical setting. Accuracy of Content evaluated agreement between the topic and content of the presentation, use of presentation aids to highlight the presentation’s key points, and adherence to time limitations.
Effective communication is not just about what you say but also about how you say it. Clarity of speech is essential to this, which includes the smooth and fluent delivery of words and phrases. Both effective communication and speech clarity are necessary for a good presentation, which involves interacting with your audience through body language, eye contact, and question-and-answer sessions. These behaviors reflect your confidence and enthusiasm, which helps engage and capture the audience’s attention.
The reliability of the tool is a crucial factor in determining its quality. Our study’s overall scale demonstrated a Cronbach’s alpha of 0.875, indicating acceptable internal consistency. The original version of the scale had a Cronbach’s α of 0.94 [2]. In terms of reliability analysis for stability, the ICC was found to be 0.965, suggesting good stability for the Persian version of the scale. In the Taiwan version, the Cronbach’s α value for the total scale was 0.94, ranging from 0.84 to 0.93 for the three factors [2].
Nursing students are exposed to various patient demographics and medical conditions, which can contribute to psychological stress due to their demanding schedules, practical coursework, and hospital internships [39]. In this context, oral presentations are vital during clinical training, as they enable students to develop crucial communication skills necessary for effectively conveying medical information. Furthermore, these presentations foster critical thinking and enhance confidence, preparing students for future healthcare roles by effectively bridging theoretical knowledge with practical application in real-world scenarios.
Limitation
This study aimed to translate and evaluate the reliability and validity of the OPES for use with Iranian nursing students. The results showed that the Persian version of the OPES is valid and reliable, suggesting it can be used to assess oral presentation skills among Iranian nursing students. However, it’s important to note that the study had limitations. It was conducted in a single university and did not include concurrent or discriminant validity assessments. The study relied on self-reported data and did not evaluate responsiveness and inter-rater reliability. Despite these limitations, the study provides a valid and reliable Persian version of the OPES, which can help Iranian nursing students develop their oral presentation skills. They can use the validated Persian version of the OPES as a self-assessment tool to evaluate and improve their skills. Nurse educators in Iran can use the OPES as an objective evaluation method to assess nursing students’ oral presentation skills and provide feedback to help students improve. In future research, it would be beneficial to evaluate the OPES in different university settings and assess its validity and reliability. Nurse educators can also use the OPES as a teaching tool by organizing workshops and training sessions to familiarize nursing students with the evaluation criteria and provide opportunities for practice and feedback on their presentation skills.
Conclusion
The Persian versions of the OPES are valid and reliable psychometric scales used to assess nursing students’ oral presentation competency. They are also a promising assessment tool that can be used in another student group. This questionnaire can be used in research and other educational settings. More studies on the validity of this scale in different educational contexts are suggested. Further studies should be conducted to reinforce the validity (the convergent and discriminant validity) of the oral presentation scale.
Acknowledgements
We would like to express our sincere gratitude to Dr. Mehri for her invaluable guidance and assistance. We also extend our thanks to the Ardabil University of Medical Sciences for their support, as well as all the professors and students who participated in the study.
Declarations
Ethics approval and consent to participate
The Ethical Committee has approved the research conducted by Ardabil University of Medical Sciences under the ethical code IR.ARUMS.REC.1402.030. To ensure that ethical standards were met, we informed all students about the purpose of the study. Only those who voluntarily agreed to participate were given anonymous questionnaires, and we collected data through these questionnaires. We ensured the privacy of the participants during the questionnaire administration process. Additionally, we requested that students who met the inclusion criteria provide their written consent. Written informed consent was obtained from all participants and their legal guardians, and we guaranteed their confidentiality. We also told participants that they could withdraw from the study anytime.
Consent for publication
Not Applicable.
Competing interests
The authors declare no competing interests.
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