Development and Validation of a Revised VAS-Anxiety Measurement Tools for Preschool Hospitalized Children

Islaeli Islaeli1,2*, Faridah Mohd Said1, Nisha Nambiar3, Nur Syazana Umar1
1Faculty of Nursing, Lincoln University College, 47301 Petaling Jaya, Selangor, Malaysia
2Mandala Waluya University, Southeast Sulawesi 93561, Indonesia

3Faculty of Applied Science Nursing, Lincoln University College, 47301 Petaling Jaya, Selangor, Malaysia

*Corresponding Author’s Email: islaeli.phd@gmail.com

ABSTRACT

Background: The visual analogue scale (VAS) instrument is proven to be reliable in measuring anxiety. Experts argue, however, that measuring the aspect of psychosocial trauma in a different language has limitations, especially among hospitalised children under the age of six. As a result, the study sought to revise and validate a trustworthy, child-friendly VAS for use in Indonesia. Methods: A preliminary survey was conducted among 81 respondents that met the inclusion criteria. An expert committee reviewed and revised the VAS-Anxiety- Indonesia for sensitivity and content validity. Thus, the Centre of Indonesia Language was charged with forward and backward translation from English to Indonesian and vice versa. In this study, data were collected in two phases. The first was the preliminary data collection from 21 respondents for face and content validity. The second phase recruited 60 respondents with retests and confirmations of modified items and components of VAS-A-Indonesia. Statistical analysis used a Pearson correlation coefficient of 0.05. The second test performed the content validity index, item correlation analysis, internal consistency for reliability testing, and Exploratory Factor Analysis. Results: The instrument consists of 12 items. With three factors to measure anxiety, they accounted for 65.2% of the overall variance. The content validity index was 0.825 (Aiken's V), item correlations ranged from 0.354 to 0.686, and Cronbach's alpha was 0.837. Conclusion: The Indonesian version of the VAS-A was a valid and reliable instrument for assessing the anxiety of preschoolers admitted to hospitals.

Keywords: Visual Analog Scale; Anxiety; Children; Hospitalization; Validity and Reliability

INTRODUCTION

Hospitalization for pre-schoolers is very stressful and potentially traumatising due to the hazardous new environment and medical procedures that can trigger anxiety, rage, powerlessness, and a loss of control (Godino-Iáez et al., 2020; Islaeli et al., 2020). The child is unable to do his routine activities Nurse Key (2020). , and the worst scenario is when the children watch strangers in white uniforms in an unfamiliar environment (Kleye et al., 2021) and are afraid of needles and syringes (Leibring & Anderzén-Carlsson, 2022). A preschooler also experiences fears at a child's developmental stage, such as fear of darkness (Csonka, 2021). Fear can be reflected in the child's behavior in the form of anxiety, increased resistance, or attempts to escape. Aggression, trouble sleeping or eating, or fear can be expressed through children's facial expressions and gestures and physiological changes in their bodies (Salmela, Aronen, & Salanterä, 2011). However, the response is highly individualised and dependent on the child's developmental age, previous illness history, and coping skills in the hospital (Kleye et al., 2021; Leibring & Anderzén-Carlsson, 2022).

Hospitalization causes children to be separated from their parents and frequently results in substantial emotional changes in children, including such anxiety, which can result in both short- and long-term trauma (Handayani & Daulima, 2020). Anxiety is the most frequently reported adverse reaction since elevated anxiety impairs children's psychological health and hinders their success in medical care. The anxiety also increases children’s uncooperative attitudes and negative feelings toward health care professionals while concurrently lowering patient satisfaction (Kleye et al., 2021; Mahakwe et al., 2021). Therefore, it is crucial to understand the level of anxiety felt by children during hospitalization. There have been several instruments measuring anxiety in the world. The most comprehensive measurements of anxiety are currently self-report instruments that provide the most direct access to the subjective experiential states of an individual in assessment situations. Its strong psychometric properties are relatively inexpensive and easy to manage and score (Mahakwe et al., 2021). The Visual Analog Scale-Anxiety (VAS-A) instrument is not difficult to administer, is easy to understand for children, and is a reliable method for evaluating subjective feelings, and is suitable for aged 3-7 years (Jiang et al., 2021; Li et al., 2016). VAS-Anxiety is a standard assessment tool instead of many other VAS versions. With one question item, this instrument is reliable and valid in measuring anxiety, VAS of a computerized version(Abend et al., 2014), VAS can assess perioperative patient anxiety (Croke, 2020), as the VAS dental anxiety (Takemura et al., 2021). In another study, the validity and reliability of the Anxiety instrument found differences in the characteristics of the VAS instrument. The other two anxiety instruments demonstrate that the VAS instrument validated and used globally is simple, easy to understand, and takes only one minute to complete. However, some experts explain that the more items on the measurement scale, the higher the level of reliability value will be (Budiastuti Dyah, 2018).

Therefore, this research aimed to develop and test a VAS-Anxiety Instrument for hospitalized children based on hospitalization theory and an anxiety instrument that focuses on children's fears and signs of anxiety. The presence of an anxiety sign item is intended to confirm the responses of participants to the first item question. The Visual Analog Scale for anxiety- revised (VAA-R) assessing anxiety in children and adolescents with school refusal has long been developed by revising the original VAS to eleven question items(Bernstein & Garfinkel, 1992), and the VAS Voice consists of four items (Naunheim et al., 2020). These items scale showed the symptoms and cause of the anxiety during care in children.

METHODOLOGY

The scale-development process was carried out in three phases. The first phase develops the instrument items based on literature reviews and pre-existing instruments. The second involves the expert panel, and the third is the psychometric analysis(Acosta-Banda et al., 2021; Morgado et al., 2017).

The First Phase : Development of VAS-Anxiety Items

This instrument item was developed from three sources: The first is the original VAS instrument, the second is a literature review, and the third is a review of existing instrument items. The original VAS for anxiety was a 100-mm horizontal line at the opposite end ("jittery/nervous" versus "steady"). unpublished instrument and other references ("anxious" and "calm"), (left, least extreme, and right, most extreme), children should mark the lines to indicate their anxiety level (Bernstein & Garfinkel, 1992), and the horizontal line should be pointed to show their situation (Mahakwe et al., 2021).

The revised VAS-Anxiety instrument develops twelve items in Indonesian. which consists of three components. Component 1 (fear with five items), component 2 (anxious mood or worry with three items), and component 3 (physiological response with four items) Each item is a 100-mm horizontal line. At the end of the line, 0 indicates no anxiety; the other side shows anxiety, and the ratings account for anxiety level. In addition, the instrument was developed in Indonesian. The translation was carried out at the Center of Language at Mandala Waluya University. With the permission of the book’s author, who published the instrument and translated it into Indonesian, this study included excerpts from the questionnaire (Nursalam, 2013; Ramdan, 2019). The items were translated forward and backward by expert translators to ensure that the meaning of each item remained consistent and accurate throughout the publication process.

The Second Phase: Expert Panel

Expert judgement determines the validity of the content. In an expert review, some grammatical and spelling issues, as well as the correction of some answer descriptors, were fixed to improve the instrument's quality (Acosta-Banda et al., 2021). The content validity is assessed based on how well the instrument content represents the overall subject, and the knowledge level (aspects) will be measured. Three experts conducted the content validity test: pediatricians, clinical psychologists, and senior nurses with over twenty years of experience. Apart from serving patients in the hospital, the experts are also a teaching team in their respective fields. The content validity was determined using the content validity index (CVI) with a 4-point rating system of relevance level (from 1 = irrelevant and 4 = highly relevant), then re-recorded as 1 (relevance scale 3 or 4) and 0 (relevance scale 1 or 2). The CVI (I-CVI) judgement of the item is calculated as the number of experts giving the relevant rating divided by the total number of experts; the I-CVI is not lower than 0.78 (Yusoff, 2019) or 0.75 (Acosta-Banda et al., 2021). In this study, the instrument was approved after the experts' revision process. Aiken's V:0,825 content validity index was confirmed (Acosta- Banda et al., 2021). Experts advise to more specific questions so that child is easier to understand, such as the content "Does Your sleep is disturbed?" revised content "Have you ever had a nightmare at the hospital?".

The Third Phase: Psychometric Analysis

After the expert panel's assessment, a preliminary test was conducted with a convenient sampling method on 21 respondents who met the inclusion criteria. Preliminary tests were conducted to determine whether the items were understood. The trial showed that participants (n = 21) had no difficulty understanding all items. Most of the participants were men (n = 16). The interviews showed that these items were understood by the participants, as was the intention of the research team. Further analysis of the revised Indonesian version of the VAS- Anxiety was carried out later on 60 respondents. The analysis method of item correlation evaluates the validity of the constructs (Igwesi-Chidobe et al., 2021; Yusoff, 2019), the exploratory factor analysis (EFA), and Cronbach's alpha coefficient for internal consistency reliability reflecting the questionnaire items for each other (Igwesi-Chidobe et al., 2021; Tsang, Royse & Terkawi, 2017).

Setting and Samples

In this study, two groups of participants were obtained using a convenience sampling method. Twenty-one and sixty respondents were recruited for the preliminary and exploratory tests, respectively. The reliability coefficient was determined through a pilot test by collecting 20 (Acosta-Banda et al., 2021), 13 participants in a preliminary study (Takemura et al., 2021), and 20 to 30 subjects not included in the research samples (Bolarinwa, 2015) Based on (Tsang, Royse & Terkawi, 2017), respondent-to-item ratio advice ranged from 5:1 there were a total of sixty respondents. The inclusion criteria of this study were children aged three to six years, having their first experience of being hospitalized, receiving intravenous therapy, and not having a diagnosis of a chronic disease. Each child is directed and accompanied by the parent during the process of filling out the instrument. This study was conducted at hospitals considered the first line of service from September 2020 to February 2021.

Data Analysis

The descriptive analysis summarizes the characteristics of the sample. All statistical tests were conducted with an alpha level of 0.05. Analysis performance was measured by the content validity index (CVI) with a four-point scoring system (from 1=not relevant to 4 = highly relevant). Item-total correlation coefficients and Cronbach's alpha after item revisions: items with a weak total item correlation coefficient or less than 0.30 will be revised or removed (Cannavan et al., 2021; Tsang, Royse, & Terkawi, 2017). The Indonesian revised VAS-Anxiety factor structure was determined using principal component analysis and varimax rotation.An absolute value was set above 0.40. the data were analyzed by SPSS software version 20.

Ethical Consideration

In this study, researchers obtained ethical approval from the hospital ethics commission on September 28, 2020, with the number: 462/RSA-III/SK/IX/2020. This survey maintained anonymity, and the data collected was kept private and used for research purposes only. The parents of the participants signed informed consent forms before the research process began.

RESULTS

Characteristics of Participants

A preliminary test was carried out with 21 respondents, and the second validity was performed with 60 respondents. The preliminary tests tested the construction, face, and content of the items. The second validity test used an exploratory test. The results of the characteristics of patients are shown in Table 1.

Table 1: Characteristics of Participants (Preliminary tests: n=21, Second for EFA: n=60)

Item Analysis

The corrected item-total correlation value determined the validity of each question item. A correlation coefficient of <0.30 indicates a weak correlation (Cannavan et al., 2021). Table 2 shows the results of the item-total correlation of the preliminary and second validity tests. The correlation between each question item on the children's anxiety variable was from Q1 to Q12. This table shows that any items should be revised.

Table 2: The Item Analysis and Reliability of The VAS-Anxiety Revised

Weak Correlarion : <0.03 Cronbach’s alpha : >0.70

On preliminary tests, items Q4, Q5, and Q8 showed findings with weak correlation (<0.30). Items having a weak correlation with the overall questionnaire score should be removed or revised(Tsang, Royse & Terkawi, 2017). Other reference argue that the higher the number of items on the measurement scale, the higher the reliability value(Bolarinwa, 2015). Therefore, in researcher decided to save and revise the context of the question. The items were revised as the advice from the three experts. (Q4: “Do your hands sweat?” was revised to “Are your palm sweaty?”), (Q5: “Do you feel dizzy?” revised to “Does your head feel dizzy?), (Q8: “Are you afraid of being alone” was revised to “Are you afraid when you are alone?). As the second validity test, all revised items indicated a higher correlation coefficient ranging from 0.354 to 0.686, showing moderate correlation (Cannavan et al., 2021).

Construct Validity

The Kaiser-Meyer-Olkin (KMO) values were 0.69, and Bartlett's test of value was X2 = 389.64 (p <0.001). Both KMO and Bartlett's tests presented that the data had adequate sampling and could be analyzed with EFA. This test had a minimum acceptable score of 0.50(Kaiser, 1974), above 0.60 (Howard, 2016). The EFA showed a three-factor solution in our sample, which accounted for 65.2% of the total variance. After the Varimax rotation using the Principal Component Analysis method, this study found that the variables/items were closely related to the factor. So, the first factor included five items, the second had three items, and the third had four items. Each items loading factor varies between 0.463 and 0.941. At least three items with loading greater than 0.40 should be retained factors. Other factors should not be overloaded by these(Samuels, 2016). Show in table 3.

Table 3: Exploratory Factor Analysis (EFA) test of the final VAS-Anxiety Revised

Factors: 1: Fear, 2: Anxious Mood, 3: Physiological Response, Loading factor: >0.40

Reliability Test

Item analysis showed that the internal consistency of the revised VAS-Anxiety instrument with the Cronbach's alpha coefficient value of 0.837 was more significant than 0.70. Therefore, the developed VAS-Anxiety instrument was considered reliable. The questionnaire was used as a research instrument if it had a reliability coefficient of 0.70 and above(Chung et al., 2021; Igwesi-Chidobe et al., 2021).

DISCUSSION

The study aimed to develop an instruments and perform its reliability tests. The instrument development resulted in 12 scale items, one item was the original question from the VAS- Anxiety instrument and eleven questions collected from a popular theory, tested for validity and reliability. The VAS-Anxiety instrument was revised in Indonesian with appropriate psychometric properties and proven through validity and reliability tests. The final version has a correlation coefficient between 0.354 to 0.686 and internal consistency with Cronbach’s alpha 0.837. These results were consistent with previous studies. The reported valid evidence has been used in several different studies, with a correlation coefficient (r) of 0.44-0.60 between the VAS and the State-Trait Anxiety Inventory (STAI) (Abend et al., 2014), The change in HAMA scores was strongly linked with Clinical Useful Anxiety Outcome Scale-D (CUXOS-D) scores (r =0.61, p <0.001)(Zimmerman et al., 2019). The correlation coefficient for item construct validity range from 0.529 to 0.727, and Cronbach’s alpha reliability was 0.756 (Ramdan, 2019).

The Preliminary test for the first item question (how anxious do you feel right now?) has an item correlation value (0.49) and decreased in the second test (0.35). However, both were in the moderate category(Cannavan et al., 2021; Igwesi-Chidobe et al., 2021). The experts agreed that the relevant item was the anxiety that the researcher wanted to know. However, the result was possible for the respondent to deny the feeling of anxiety (Salmela, Aronen & Salanterä, 2011). The hospitalized pre-school children interpreted a form of anxiety with rejection where they expressed their anxiety in contradictory ways or denied it. It can be seen in Cronbach's alpha if the item on the deleted column increase from (0.786 to 0.834). This column is considered necessary, representing the reliability coefficient of the Cronbach alpha scale for internal consistency with an increase in Cronbach alpha if items deleted on each item will cause the value of the Cronbach alpha coefficient to increase( Gliem & Gliem, 2003).

This study also found that the preliminary test items (Q4, Q5, and Q8) were weak in correlation value of <0.30. However, revisions were made according to the previous discussion on the results item analysis points. In the second test, there was an increase in the value of both the item-total correlation and Cronbach's alpha if item deleted column. Moreover, Cronbach's alpha coefficient value increased from the preliminary and second tests (0.804 to 0.834), meaning acceptable reliability (Acosta-Banda et al., 2021).

The four components with eigenvalues are more than one in EFA analysis. However, Rotation sum of Square Loadings had three factors. So this study used the rotated eigenvalues (Igwesi-Chidobe et al., 2021). No items were deleted due to the three-component rotated matrix, with a loading factor of more than 0.40. Furthermore, each item only had a high factor loading on one factor. This factor was labeled factor 1 (fear), factor 2 (Anxious mood), and factor 3 (Physiological). Similar to the factors on the RSMC instrument (Bernstein & Garfinkel, 1992). Factor 1 was appropriate in the study (Salmela, Salanterä, & Aronen, (2010) that hospitalized children would cause fear of separation from family and fear of being left alone, fear of doctors /nurses, and nightmares. So, the question items became "Does your head feel dizzy"? In addition, "Do you feel trembling"? had a significant factor loading in the factor 1 group, so that these two items were included in the fear factor. In the HAM-A instrument, these two items are distinguished on their autonomic symptoms and behavior. Factor 2, as the developmental theory indicating the typical fear in preschool-age development (6, 32) was fear of darkness and fear of sleeping alone. The two fears were interrelated that the rooms darkness could "ghosts", which made the child more worried.

Moreover, Factor 3 was a physiological response. When someone experiences feelings of anxiety with the question item "do you lack appetite?", "how anxious do you feel right now?", "do you feel getting short of breath?" and "does you feel palpitations?". One of the disadvantages of EFA analysis is the difficulty in defining the factors. The names of factors may not accurately reflect the variables that make up the factor (An Gie Yong, 2013). However, Variables with higher loadings are seen as more significant. They have an enormous impact on the name or label chosen to describe a factor (Hair et al., 2014).

However, this research was limited to the Covid 19 pandemic. The researcher had less contact with patients and used personal protective equipment, e.g., eye patches, gogles, surgical masks, gowns, and gloves. Such a condition was ineffective in communicating with children who appeared more anxious. The question items were 12 items to be more flexible in determining more specific items. There is still a lack of experts who give judgments.

CONCLUSION

The Indonesian version of the VAS-Anxiety instrument was based on review and expert judgment literature consisting of 12 question items. The preliminary test results found three items with a weak correlation (<0.30). All three items were based on expert advice. Secondary test showed excellent validity and reliability results (0.837) in the appropriate sample. The exploratory factor analysis (EFA), after varimax rotation with the principal component analysis method, found at least three items with loading factor (>0.40), others factor did not burden each factor. This instrument formed three factors, namely factor 1 (fear : 5 items), factor 2 (worry : 3 items), and factor 3 (physiological response:4 items), that can measure the anxiety of pre-schoolers who are hospitalized.

Conflict of Interest

The authors declare that they have no conflict of interests.

ACKNOWLEDGEMENT

The authors are thankful to the parents and children who participated in this study, as well as the hospital management and medical staff for helping to carry out the study.

REFERENCES

Abend, R., Dan, O., Maoz, K., Raz, S., & Bar-haim, Y. (2014). Journal of Behavior Therapy and Reliability , validity and sensitivity of a computerized visual analog scale measuring state anxiety. Journal of Behavior Therapy and Experimental Psychiatry, 45(4), 447–453. https://doi.org/10.1016/j.jbtep.2014.06.004

Acosta-Banda, A., Aguilar-Esteva, V., Ortiz, M. P., & Ortiz, J. P. (2021). Construction and validity of an instrument to evaluate renewable energies and energy sustainability perceptions for social consciousness. Sustainability (Switzerland), 13(4), 1–13. https://doi.org/10.3390/su13042333

An Gie Yong, S. P. (2013). A Beginner’s Guide to Factor Analysis: Focusing on Exploratory Factor Analysis. Tutorials in Quantitative Methods for Psychology, 9(2), 79–94. https://doi.org/10.20982/tqmp.09.2.p079

Bernstein, G. A., & Garfinkel, B. D. (1992). The visual analogue scale for anxiety - Revised: Psychometric properties. Journal of Anxiety Disorders, 6(3), 223–239. https://doi.org/10.1016/0887-6185(92)90035-6

Bolarinwa, O. (2015). Principles and methods of validity and reliability testing of questionnaires used in social and health science researches. Nigerian Postgraduate Medical Journal, 22(4), 195. https://doi.org/10.4103/1117-1936.173959

Budiastuti, D., & Bandur, A. (2018). Validitas dan reliabilitas penelitian. Jakarta: Mitra Wacana Media

Cannavan, P. M. S., De Souza Cannavan, F. P., Oliveira, H. C., Walfridsson, U., & De Moraes Lopes, M. H. B. (2021). A Brazilian Portuguese translation, cultural adaptation and validation of the Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia (ASTA) health-related quality of life (HRQOL) scale. PLoS ONE, 16(8 August), 1–15. https://doi.org/10.1371/journal.pone.0256851

Chung, J. O. K., Li, W. H. C., Wei, X., Cheung, A. T., Ho, L. L. K., & Chan, G. C. F. (2021). Translation and psychometric evaluation of the Chinese version of the resilience scale for children with cancer. Health and Quality of Life Outcomes, 19(1), 1–9. https://doi.org/10.1186/s12955-021-01865-y

Croke, L. (2020). Nonpharmacologic strategies to help reduce preoperative patient anxiety. AORN Journal, 111(2), P8–P10. https://doi.org/10.1002/aorn.12970

Csonka, S. (2021). Why be afraid of the night ? - Pedagogical methods for developing positive attitudes towards natural darkness in order to reduce light pollution. 11(2), 18–35. https://doi.org/10.24368/jates.v11i2.222

Godino-Iáñez, M. J., Martos-Cabrera, M. B., Suleiman-Martos, N., Gómez-Urquiza, J. L., Vargas-Román, K., Membrive-Jiménez, M. J., & Albendín-García, L. (2020). Play therapy as an intervention in hospitalized children: A systematic review. Healthcare (Switzerland), 8(3), 1–12. https://doi.org/10.3390/healthcare8030239

Gliem, J. A., & Gliem, R. R. (2003). Calculating, interpreting, and reporting Cronbach’s alpha reliability coefficient for Likert-type scales. Midwest Research-to-Practice Conference in Adult, Continuing, and Community Education.

Hair J. F., Black W. C. Babin B. J., & Anderson R. E. (2019). Multivariate data analysis (Eighth). Pearson New International Edition. UK.

Handayani, A., & Daulima, N. H. C. (2020). Parental presence in the implementation of atraumatic care during children’s hospitalization. Pediatric Reports, 12. https://doi.org/10.4081/pr.2020.8693

Howard, M. C. (2016). A Review of Exploratory Factor Analysis Decisions and Overview of Current Practices: What We Are Doing and How Can We Improve? International Journal of Human-Computer Interaction, 32(1), 51–62. https://doi.org/10.1080/10447318.2015.1087664

Igwesi-Chidobe, C. N., Muomah, R. C., Sorinola, I. O., & Godfrey, E. L. (2021). Detecting anxiety and depression among people with limited literacy living with chronic low back pain in Nigeria: adaptation and validation of the hospital anxiety and depression scale. Archives of Public Health, 79(1), 1–16. https://doi.org/10.1186/s13690-021-00586-4

Islaeli, I., Yati, M., Islamiyah, & Fadmi, F. R. (2020). The effect of play puzzle therapy on anxiety of children on preschooler in Kota Kendari hospital. Enfermeria Clinica, 30, 103– 105. https://doi.org/10.1016/j.enfcli.2019.11.032

Jiang, M., Ma, Y., Li, M., Meng, R., Ma, A., & Chen, P. (2021). A comparison of self- reported and proxy-reported health utilities in children: a systematic review and meta- analysis. Health and Quality of Life Outcomes, 19(1), 1–14. https://doi.org/10.1186/s12955- 021-01677-0

Kaiser, H. F. (1974). An index of factorial simplicity. Psychometrika, 39(1), 31–36. https://doi.org/10.1007/BF02291575

Kleye, I., Hedén, L., Karlsson, K., Sundler, A. J., & Darcy, L. (2021). Children’s individual voices are required for adequate management of fear and pain during hospital care and treatment. Scandinavian Journal of Caring Sciences, 35(2), 530–537. https://doi.org/10.1111/scs.12865

Leibring, I., & Anderzén-Carlsson, A. (2022). Young children’s experiences of support when fearful during treatment for acute lymphoblastic leukaemia—A longitudinal interview study. Nursing Open, 9(1), 527–540. https://doi.org/10.1002/nop2.1092

Li, W. H. C., Chung, J. O. K., Ho, K. Y., & Kwok, B. M. C. (2016). Play interventions to reduce anxiety and negative emotions in hospitalized children. BMC Pediatrics, 16(36), 1–9. https://doi.org/10.1186/s12887-016-0570-5

Mahakwe, G., Johnson, E., Karlsson, K., & Nilsson, S. (2021). A Systematic Review of Self- Report Instruments for the Measurement of Anxiety in Hospitalized Children with Cancer. International Journal of Environmental Research and Public Health, 18. https://doi.org/10.3390/ijerph18041911

Morgado, F. F. R., Meireles, J. F. F., Neves, C. M., Amaral, A. C. S., & Ferreira, M. E. C. (2017). Scale development: Ten main limitations and recommendations to improve future research practices. Psicologia: Reflexao e Critica, 30(1), 1–20.https://doi.org/10.1186/s41155-016-0057-1

Naunheim, M. R., Dai, J. B., Rubinstein, B. J., Goldberg, L., Weinberg, A., & Courey, M. S. (2020). A visual analog scale for patient-reported voice outcomes: The VAS voice. Laryngoscope Investigative Otolaryngology, 5(1), 90–95. https://doi.org/10.1002/lio2.333

Nursalam. (2013). Nursing Research Methodology: Practical Approaches 3rd edition (Aklia Suslia (ed.)). Salemba Medika.

Nurse Key (Fastest Nurse Insight Engine). Concepts in pediatric nursing care Just the facts. https://nursekey.com/concepts-in-pediatric-nursing-care/

Ramdan, I. M. (2019). Reliability and Validity Test of the Indonesian Version of the Hamilton Anxiety Rating Scale (HAM-A) to Measure Work-related Stress in Nursing. Jurnal Ners, 14(1), 33. https://doi.org/10.20473/jn.v13i2.10673

Salmela, M., Aronen, E. T., & Salanterä, S. (2011). The experience of hospital-related fears of 4- to 6-year-old children. Child: Care, Health and Development, 37(5), 719–726. https://doi.org/10.1111/j.1365-2214.2010.01171.x

Salmela, M., Salanterä, S., & Aronen, E. T. (2010). Coping with hospital‐related fears: experiences of pre‐school‐aged children. Journal of Advanced Nursing, 66(6), 1222-1231. https://doi.org/10.1111/j.1365-2648.2010.05287.x

Samuels, P. (2016). Advice on Exploratory Factor Analysis. Centre for Academic Success, Birmingham City University, June, 2. https://doi.org/10.13140/RG.2.1.5013.9766

Takemura, Y., Kido, K., Kawana, H., Yamamoto, T., Sanuki, T., & Mukai, Y. (2021). Effects of green color exposure on stress, anxiety, and pain during peripheral intravenous cannulation in dental patients requiring sedation. International Journal of Environmental Research and Public Health, 18(11). https://doi.org/10.3390/ijerph18115939

Tsang, S., Royse, C. F., & Terkawi, A. S. (2017). Guidelines for developing, translating, and validating a questionnaire in perioperative and pain medicine. Saudi Journal of Anaesthesia, 11, S80–S89. https://doi.org/10.4103/sja.SJA_203_17

Yusoff, M. S. B. (2019). ABC of Content Validation and Content Validity Index Calculation. Education in Medicine Journal, 11(2), 49–54. https://doi.org/10.21315/eimj2019.11.2.6

Zimmerman, M., Kiefer, R., Kerr, S., & Balling, C. (2019). Reliability and validity of a self- report scale for daily assessments of the severity of anxiety symptoms. Comprehensive Psychiatry, 90, 37–42. https://doi.org/10.1016/J.COMPPSYCH.2018.12.014