PONE-D-23-03780Psychometric Properties of the GAD-7: Evidence from MalaysiaPLOS ONE

Dear Dr. Tan,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

==============================An expert in the field of psychometrics has reviewed the paper and is believed the the contribution can add something to the literature. Therefore, I welcome the authors to revise their work according to the reviewer's comments. In addition, I would like the authors to further address the following two points.1. Please provide demographic information of the two separated samples (one for CFA and another for EFA) to let the readers know if the two samples are equivalent.2. Regarding the reviewer's comment on the use of English version in the present sample, please use the references of Gan et al., and Tung et al. to make justification.Gan, W. Y., Tung, S. E. H., Kamolthip, R., Ghavifekr, S., Chirawat, P., Nurmala, I., Chang, Y.-L., Latner, J. D., Huang, R.-Y., & Lin, C.-Y. (2022). Evaluation of two weight stigma scales in Malaysian university students: Weight Self-Stigma Questionnaire and Perceived Weight Stigma Scale. Eating and Weight Disorders, 27, 2595-2604.Tung, S. E. H., Gan, W. Y., Chen, J.-S., Kamolthip, R., Pramukti, I., Nadhiroh, S. R., Chang, Y.-L., Lin, C.-C., Pakpour, A. H., Lin, C.-Y., Griffiths, M. D. (2022). Internet-related instruments (Bergen Social Media Addiction Scale, Smartphone Application-Based Addiction Scale, Internet Gaming Disorder Scale-Short Form, and Nomophobia Questionnaire) and their associations with distress among Malaysian university student. Healthcare, 10, 1448.

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Chung-Ying Lin

Academic Editor

PLOS ONE

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Reviewer #1: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

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Reviewer #1: No

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Reviewer #1: Yes

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5. Review Comments to the Author

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Reviewer #1: I appreciate the opportunity to read this work and provide feedback. This manuscript attempted to examine the factor structure of GAD-7 in the Malaysian context with the use of EFA and CFA. The authors suggested a 6-item second-order model with a general factor of anxiety and three first-order factors (GAD-6). Overall, I believe the research has the potential to make a valuable contribution to the field. However, there are a few areas where I believe the manuscript could be strengthened.

1. I am curious about the reason for using the English version in this study. Specifically, the authors mentioned that "GAD-7 has demonstrated good screening properties among women attending primary care clinics in Malaysia (Mohd Sidik et al., 2012)", which was the Malay version. Therefore, please discuss your decision on using the English version of GAD-7 in investigating its factor structure in the Malaysian context.

2. Please provide more details about GAD-7 usage in Malaysia. Which language version, Malay or English, was typically employed for studies using the GAD-7 in Malaysia?

3. Is the study by Mohd Sidik et al. (2012) the only GAD-7 psychometric study done in Malaysia?

4. The authors mentioned that there is a Supplementary Table S1. However, I cannot find it. I am not sure if it is the fault of the system or if the author forgot to upload. I would appreciate it if the authors could upload it again.

5. ECVI was used to compare the models in this study, however, this is not mentioned in the analysis section. Please add the information.

6. Also, the descriptive statistics, inter-factor correlations, and the software to calculate them were not mentioned in the analysis section.

7. Regarding the subscales of the final GAD-6, the author named the three factors as expectation factor, autonomic excitation factor, and anxious distress factor. And later, the authors used the terms “cognitive subscale” and “somatic subscale”, which is confusing. I think discussion is needed for these names.

8. For the CFA, authors adopted factor structures from previous studies. Please add references for those models.

9. I think the manuscript title can emphasize factor structure.

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Reviewer #1: No

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Factorial Structure, Reliability, and Construct Validity of the Generalized Anxiety Disorder 7-item (GAD-7): Evidence from Malaysia

PONE-D-23-03780R1

Dear Dr. Tan,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Chung-Ying Lin

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

The authors have improved their contribution with the use of suggestions from the reviewer and I. Good job. 

Reviewers' comments: