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Reliability and validity of the Japanese version of the weight bias internalization scale



The weight bias internalization scale (WBIS) is widely used in several languages. However, there is no Japanese version of the WBIS. The purpose of this study is to develop a Japanese version of the WBIS and to verify its reliability and validity. We translated the original version of the WBIS and had approval from the scale developer. Adults who perceived themselves to be obese completed online baseline survey (N = 285) and two-week follow-up survey (N = 100). We used the Japanese WBIS and scales for obesity-related quality of life, self-esteem, self-efficacy, and depression. We calculated Cronbach’s alpha and intra-class correlation coefficient (ICC) to assess reliability of the WBIS and conducted confirmatory factor analysis (CFA) and correlation analysis to assess its validity.


Cronbach’s alpha was 0.91 at baseline and 0.92 at follow-up, and the ICC was 0.87. CFA showed that a one-factor model demonstrated an acceptable fit (χ2 (44) = 158.6, CFI = 0.93, RMSEA = 0.096, SRMR = 0.051), similar to the original version. As we had hypothesized, overall, the Japanese version of the WBIS was significantly correlated with obesity-related quality of life, self-esteem, self-efficacy, and depression. These results confirmed its adequate reliability and validity.


People with obesity are highly stigmatized and face discrimination and prejudice because of their weight [1]. The weight stigma about obesity is thought to be rooted in the misconception that body weight is easily controlled by changing the diet and physical activity levels [2]. Weight stigma internalization refers to “internalization of negative weight stereotypes and subsequent self-disparagement” [3]. Weight stigma internalization is associated with poor psychological [3,4,5], physical [5,6,7,8], and social [8,9,10] outcomes. Therefore, it is important for healthcare professionals [8, 11], social media [12, 13], and public health policy makers [14] not to exacerbate weight bias.

There are several self-reported questionnaires about internalized weight bias, among which weight bias internalization scale (WBIS) [15] is the most used. A previous study compared the WBIS and the Weight Self-Stigma Questionnaire and showed a higher reliability of the former [16]. The original version of the WBIS is in English, and it has been translated into several languages [17,18,19], including Asian languages [20]. However, a Japanese version of the WBIS has not yet been developed.

In Japan, the government began a health checkup for abdominal obesity in 2008, but the prevalence of obesity has not decreased between 2009 and 2019, with approximately 30% in males and 20% in females [21]. Although the health checkup has promoted awareness of obesity, previous studies have raised concerns that awareness-based approaches to obesity prevention could lead to unintended consequences from weight stigma [22, 23]. Japanese young females perceived high pressure from social media to be thin [24] and, dissatisfied with and concerned about their bodies [25]. In Japanese adolescents, 16% of males and 32% of females experienced body-related teasing in school and/or at home, and the experience associated with the perception to be overweight [26]. Despite this society-wide obsession against obesity, little is known about the potential harm of weight bias internalization in Japan. Weight bias toward individuals has been shown to exist in Japan as in other countries [27]. A previous study has shown that weight bias internalizes individuals when they perceived negative responses from others regarding their weight or body shape [3]. We hypothesized that weight bias internalization can play an important role in Japan. The aim of this study is to develop a Japanese version of the WBIS and to verify its reliability and validity.



We conducted a baseline and two-week follow-up online survey in April 2021. An Internet survey company, Macromill, Inc. [28], recruited participants based on the following inclusion criteria: (a) those who live in Japan and whose native language is Japanese, (b) those aged ≥ 20 years, and (c) those who perceive themselves to be obese. The perception of obesity was assessed by the same question as in the original WBIS (Appendix for details). Macromill could access to over 2,000,000 monitors representing all prefecture in Japan. Participants of this study were drawn from their monitor registered as respondents of the company. Of the available respondents, 285 participants completed a web-based questionnaire in the baseline survey. After two weeks, the company invited the responders of the baseline survey to participate in the follow-up survey in order of arrival and 100 participants completed the follow-up survey. Responses were anonymous.


Baseline survey included the Japanese version of the WBIS and scales for obesity-related quality of life, self-esteem, self-efficacy, and depression. Follow-up survey included the Japanese version of the WBIS.

The original version of the WBIS is an 11-item questionnaire that measures weight-related self-stigma and has a one-factor structure [15]. These items are scored on a 7-point Likert scale, ranging from 1 (strongly disagree) to 7 (strongly agree). Higher scores indicate more internalization of weight bias. The Japanese version of the WBIS was developed through three steps. First, two authors who were native Japanese speakers independently forward translated the original WBIS into Japanese and combined the two Japanese translations into one. Second, back-translation was conducted by a native English translator who was blinded to the original scale. Third, the original scale developer reviewed the English translation produced in the second step. Based on the suggestions of the developer, several items were modified by repeating the forward and backward translation procedures to reflect the original meaning after translation. Finally, we obtained the permission of the scale developer and used the Japanese version of the WBIS. The back-translation of the Japanese WBIS is provided in Appendix.

Obesity-related quality of life was evaluated using the Japanese version of the Obesity and Weight Loss Quality of Life Questionnaire (OWLQOL) [29, 30]. As the same as the original, it is composed of 17 items rated on a 5-point Likert scale. As a negative correlation was previously demonstrated between weight bias internalization and weight-related quality of life [31], a negative correlation would be expected between the WBIS and the OWLQOL.

Self-esteem was evaluated using the Japanese version [32] of the Rosenberg Self-Esteem Scale (RSES) [33]. As with the original, the Japanese version [32] is composed of 10 items rated on a 4-point Likert scale. A strong negative correlation was reported between the WBIS and the RSES [15].

Self-efficacy was evaluated using the General Self-Efficacy Scale (GSES) [34], which has 16 items rated on dichotomous (yes/no) scale. Weight bias internalization was reported to be associated with lower self-efficacy [35]; therefore, the present study predicted a negative correlation between the WBIS and the GSES.

Depression was evaluated using the Japanese version [36] of the Center for Epidemiologic Studies Depression Scale(CES-D) [37]. Both the original and its Japanese version [36] are composed of 20 items rated on a 4-point Likert scale. A strong positive correlation was reported between the WBIS and the CES-D [19].

Statistical analyses

We calculated the Cronbach’s alpha for internal consistency and the intra-class correlation coefficient (ICC) for test-retest reliability. Confirmatory factor analysis (CFA) was also conducted for structural validity. In CFA, we assumed a one-factor model as observed in the previous study [38]. The indicators of model fit were chi-square, comparative fit index (CFI), root mean square error of approximation (RMSEA), and standardized root mean square residual (SRMR). A good fit was indicated by a value of 0.95 or more for the CFI, 0.06 or less for the RMSEA, and 0.08 or less for SRMR [39]. To evaluate convergent validity, we calculated Pearson’s correlation coefficients between the WBIS and OWLQOL, RSES, GSES, or CES-D in the baseline survey. The minimum effect size for detection in this study was 0.20. Based on a sample size calculation using G-power version, the necessary sample size was estimated to be more than 255 in the case of an alpha error probability of 0.05 and p power (1-β) of 0.90. In the test-retest reliability analysis, the sample size could be considered excellent when more than 100 participants were recruited [40]. Therefore, the numbers of participants in this study, 285 at baseline survey and 100 at follow-up survey, were adequate.

P-value below 0.05 was regarded as statistically significant. Data were analyzed using SPSS ver. 23, and CFA was performed using AMOS version 23.0.


Demographic characteristics of the participants at baseline and follow-up survey are in Table 1. In the baseline survey (N = 285, 151 females and 134 males, mean age = 47.7 ± 13.5), the mean BMI was 25.0 (SDs = 3.5). In BMI categories, about half of the participants were normal weight. Characteristics of the participants at the follow-up survey (N = 100, 55 females and 45 males, mean age = 46.5 ± 13.5) did not differ from the baseline survey.

Table 1 Demographic characteristics of the participants.

Cronbach’s alpha of the Japanese WBIS, as a measure of internal consistency, was 0.91 at baseline and 0.92 at follow-up. The ICC, as a measure of test-retest reliability, was 0.87 (p < 0.01) calculated using longitudinal data of 100 participants.

The results of CFA are shown in Fig. 1. The one-factor hypothesized model demonstrated acceptable fit (χ2 (44) = 158.6, CFI = 0.93, RMSEA = 0.096, SRMR = 0.051). Table 2 shows the correlation coefficients between the Japanese WBIS and OWLQOL, RSES, GSES, or CES-D. The total scores of the Japanese WBIS had a moderate positive correlation with CES-D, a moderate negative correlation with GSES, and strong negative correlations with OWLQOL and RSES.

Fig. 1
figure 1

CFA path diagram of the Japanese version of the WBIS (N = 285). Factor loadings were standardized. χ2 (44) = 158.6, CFI = 0.93, RMSEA = 0.096, SRMR = 0.051

Table 2 Convergent validity of the Japanese version of the WBIS (N = 285).


The purpose of this study was to develop a Japanese version of the WBIS and to verify its reliability and validity. We finished the translation process and conducted the analysis. The results supported most of our hypotheses indicating that the Japanese WBIS showed good internal consistency, test-retest reliability, and convergent validity. The CFA showed acceptable results although RMSEA was higher than the cut off value of 0.06. This may be due to the sample size of the present study as RMSEA tends to be high with small sample size such as 250 [39].

The mean (SD) of the Japanese version WBIS was 43.1 (12.1), close to that of the original version [15]. The existence of obesity stigma was widely confirmed in Japan [27], although Japan has a low obesity rate. Social discrimination against people with obesity can lead to further obesity [40] and can prevent weight loss [41]. Flint et al., recommended that healthcare professionals working with people with obesity need to be educated about reducing weight bias internalization [42]. Cognitive-behavioral intervention study targeting weight stigma was conducted and produced short-term reductions in WBIS [43]. Measuring WBI is therefore needed both in society and in individuals to help reduce the number of people with obesity and overweight in Japan. The use of the Japanese version of the WBIS would be valuable to assess the levels of weight bias internalization in individuals in daily clinical practice and intervention studies.

In conclusion, we developed the Japanese version of the WBIS, and demonstrated that it has adequate psychometric properties, internal consistency, test-retest reliability, structural validity, and convergent validity for Japanese adults.


First, this study was conducted thorough an Internet-based survey, which might lead to a selection bias as those with high internalized weight stigma may be reluctant to participate in the Internet survey. In addition, the generalizability of this study could be questioned. Second, the response rate and dropout rate could not be calculated since the Internet survey company recruited participants until the target number of participants.

Data availability

The raw data generated during this study are included in Additional file 1. The datasets analyzed during the current study are available from the corresponding author on reasonable request.



Weight stigma internalization scale.


Obesity and weight loss quality of life questionnaire.


General Self-Efficacy Scale.


Center for Epidemiologic Studies Depression Scale.


intra-class correlation coefficient.


confirmatory factor analysis.


comparative fit index.


root mean square error of approximation.


standardized root mean square residual.


  1. Puhl R, Brownell KD. Bias, discrimination, and obesity. Obes Res. 2001;9(12):788–805.

    Article  CAS  Google Scholar 

  2. Ending weight bias. and the stigma of obesity. Nat Rev Endocrinol. 2020;16(5):253.

    Article  Google Scholar 

  3. Pearl RL, Puhl RM. Weight bias internalization and health: a systematic review. Obes Rev. 2018;19(8):1141–63.

    Article  CAS  Google Scholar 

  4. Carels RA, Wott CB, Young KM, Gumble A, Koball A, Oehlhof MW. Implicit, explicit, and internalized weight bias and psychosocial maladjustment among treatment-seeking adults. Eat Behav. 2010;11(3):180–5.

    Article  CAS  Google Scholar 

  5. Latner JD, Durso LE, Mond JM. Health and health-related quality of life among treatment-seeking overweight and obese adults: associations with internalized weight bias. J Eat Disord. 2013;1:3.

    Article  Google Scholar 

  6. Pearl RL, Wadden TA, Hopkins CM, Shaw JA, Hayes MR, Bakizada ZM, et al. Association between weight bias internalization and metabolic syndrome among treatment-seeking individuals with obesity. Obes (Silver Spring). 2017;25(2):317–22.

    Article  CAS  Google Scholar 

  7. Puhl RM, Moss-Racusin CA, Schwartz MB. Internalization of weight bias: Implications for binge eating and emotional well-being. Obes (Silver Spring). 2007;15(1):19–23.

    Article  Google Scholar 

  8. Hunger JM, Major B, Blodorn A, Miller CT. Weighed down by stigma: How weight-based social identity threat contributes to weight gain and poor health. Soc Personal Psychol Compass. 2015;9(6):255–68.

    Article  Google Scholar 

  9. Jung FU, Luck-Sikorski C. Overweight and Lonely? A Representative Study on Loneliness in Obese People and Its Determinants. Obes Facts. 2019;12(4):440–7.

    Article  Google Scholar 

  10. Roberto CA, Sysko R, Bush J, Pearl R, Puhl RM, Schvey NA, et al. Clinical correlates of the weight bias internalization scale in a sample of obese adolescents seeking bariatric surgery. Obes (Silver Spring). 2012;20(3):533–9.

    Article  Google Scholar 

  11. Hopkins CM, Bennett GG. Weight-Related Terms Differentially Affect Self-Efficacy and Perception of Obesity. Obes (Silver Spring). 2018;26(9):1405–11.

    Article  Google Scholar 

  12. Ata RN, Thompson JK. Weight bias in the media: a review of recent research. Obes Facts. 2010;3(1):41–6.

    Article  Google Scholar 

  13. Sievert K, Lobstein T, Baker P. Stigmatizing images in the media - a cross-national survey. Clin Obes. 2018;8(6):407–10.

    Article  CAS  Google Scholar 

  14. Puhl RM, Heuer CA. Obesity stigma: important considerations for public health. Am J Public Health. 2010;100(6):1019–28.

    Article  Google Scholar 

  15. Durso LE, Latner JD. Understanding self-directed stigma: development of the weight bias internalization scale. Obes (Silver Spring). 2008;16(Suppl 2):80–6.

    Article  Google Scholar 

  16. Hübner C, Schmidt R, Selle J, Köhler H, Müller A, de Zwaan M, et al. Comparing Self-Report Measures of Internalized Weight Stigma: The Weight Self-Stigma Questionnaire versus the Weight Bias Internalization Scale. PLoS One. 2016;11(10):e0165566.

    Article  Google Scholar 

  17. Macho S, Andrés A, Saldaña C. Validation of the modified weight bias internalization scale in a Spanish adult population. Clin Obes. 2021;11(4):e12454.

    Article  Google Scholar 

  18. Hilbert A, Baldofski S, Zenger M, Löwe B, Kersting A, Braehler E. Weight bias internalization scale: psychometric properties and population norms. PLoS One. 2014;9(1):e86303.

    Article  Google Scholar 

  19. Innamorati M, Imperatori C, Lamis DA, Contardi A, Castelnuovo G, Tamburello W, et al. Weight Bias Internalization Scale Discriminates Obese and Overweight Patients with Different Severity Levels of Depression: the Italian Version of the WBIS. Curr Psychol. 2017;36:242–51.

    Article  Google Scholar 

  20. Chen H, Ye YD. Validation of the Weight Bias Internalization Scale for Mainland Chinese Children and Adolescents. Front Psychol. 2021;11:594949.

    Article  Google Scholar 

  21. National Institute of Health and Nutrition. Health Japan 21 (the second term). Accessed 15 Aug 2022.

  22. Dollar E, Berman M, Adachi-Mejia AM. Do No Harm: Moving Beyond Weight Loss to Emphasize Physical Activity at Every Size. Prev Chronic Dis. 2017;14:E34.

    Article  Google Scholar 

  23. Sonneville KR, Thurston IB, Milliren CE, Kamody RC, Gooding HC, Richmond TK. Helpful or harmful? Prospective association between weight misperception and weight gain among overweight and obese adolescents and young adults. Int J Obes (Lond). 2016;40(2):328–32.

    Article  CAS  Google Scholar 

  24. Ando K, Giorgianni FE, Danthinne ES, Rodgers RF. Beauty ideals, social media, and body positivity: A qualitative investigation of influences on body image among young women in Japan. Body Image. 2021;38:358–69.

    Article  Google Scholar 

  25. Maezono J, Hamada S, Sillanmäki L, Kaneko H, Ogura M, Lempinen L, Sourander A. Cross-cultural, population-based study on adolescent body image and eating distress in Japan and Finland. Scand J Psychol. 2019;60(1):67–76.

    Article  Google Scholar 

  26. Chisuwa-Hayami N, Haruki T. Associations of body-related teasing with weight status, body image, and dieting behavior among Japanese adolescents. Health Promot Perspect. 2016;7(2):80–7.

    Article  Google Scholar 

  27. Marini M, Sriram N, Schnabel K, Maliszewski N, Devos T, Ekehammar B, et al. Overweight People Have Low Levels of Implicit Weight Bias, but Overweight Nations Have High Levels of Implicit Weight Bias. PLoS ONE. 2013;8(12):e83543.

    Article  Google Scholar 

  28. Macromill I. Corporate Profile. Accessed 3 Mar 2022. (in Japanese).

  29. Patrick DL, Bushnell DM, Rothman M. Performance of two self-report measures for evaluating obesity and weight loss. Obes Res. 2004;12(1):48–57.

    Article  Google Scholar 

  30. Sasai H, Matsuo T, Katayama Y, Kim MJ, Seino S, Ohkubo H, et al. Psychometric evaluation of Japanese version of the obesity-specific QoL measures: the obesity and weight loss quality of life questionnaire and the weight-related symptom measure. Himankenkyu. 2008;14(2):120–7. (in Japanese).

    Google Scholar 

  31. Walsh OA, Wadden TA, Tronieri JS, Chao AM, Pearl RL. Weight Bias Internalization Is Negatively Associated With Weight-Related Quality of Life in Persons Seeking Weight Loss. Front Psychol. 2018;9:2576.

    Article  Google Scholar 

  32. Mimura C, Griffiths P. A Japanese version of the Rosenberg Self-Esteem Scale: translation and equivalence assessment. J Psychosom Res. 2007;62(5):589–94.

    Article  Google Scholar 

  33. Rosenberg M. Society and the Adolescent Self-Image. Princeton Legacy Library; 1965.

  34. Sakano Y, Tohjoh M. The General Self-Efficacy Scale (GSES): scale development and validation. Jpn J Behav Ther. 1986;12:73–82. (in Japanese).

    Google Scholar 

  35. Pearl RL, Puhl RM, Himmelstein MS, Pinto AM, Foster GD. Weight Stigma and Weight-Related Health: Associations of Self-Report Measures Among Adults in Weight Management. Ann Behav Med. 2020;54(11):904–14.

    Article  Google Scholar 

  36. Shima S, Shikano T, Kitamura T, Asai M. New self-rating scale for Depression. Jpn J Clin Psychiatr. 1985;27:717–23. (in Japanese).

    Google Scholar 

  37. Radloff LS. The CES-D scale: a self-report depression scale for research in the general population. Appl Psychol Meas. 1977;1(3):385–401.

    Article  Google Scholar 

  38. Lee MS, Dedrick RF. Weight Bias Internalization Scale: Psychometric properties using alternative weight status classification approaches. Body Image. 2016;17:25–9.

    Article  Google Scholar 

  39. Hu LT, Bentler PM. Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives. Struct equation modeling: multidisciplinary J. 1999;6(1):1–55.

    Article  Google Scholar 

  40. Huang H, Yan Z, Chen Y, Liu F. A social contagious model of the obesity epidemic. Sci Rep. 2016;6:37961.

    Article  CAS  Google Scholar 

  41. Olson KL, Lillis J, Graham Thomas J, Wing RR. Prospective Evaluation of Internalized Weight Bias and Weight Change Among Successful Weight-Loss Maintainers. Obes (Silver Spring). 2018;26(12):1888–92.

    Article  Google Scholar 

  42. Flint SW, Raisborough J, Hudson J. Editorial. The Implications of Weight Bias Internalization. Front Psychol. 2020;10:2019–21.

    Article  Google Scholar 

  43. Pearl RL, Wadden TA, Bach C, Gruber K, Leonard S, Walsh OA, et al. Effects of a cognitive-behavioral intervention targeting weight stigma: A randomized controlled trial. J Consult Clin Psychol. 2020;88(5):470–80.

    Article  Google Scholar 

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The authors would like to thank Oliver Stanyon for back-translation of the Japanese version of the WBIS. We also thank Kasumi Ouchi (Office for Gender Equality Support in Fukushima medical university) for assistance with manuscript preparation.


This work was supported by JSPS KAKENHI (Grant Number JP19K19438).

Author information

Authors and Affiliations



SE designed and managed the study, translated the WBIS, analyzed the data, and wrote the initial draft of the manuscript. KH designed the study, translated the WBIS, analyzed the data, and supervised the overall study implementation. YN, TH, TK, and TF designed the study, contributed to interpretation of the data and assisted in the preparation of the manuscript. TF supervised the entire process. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Shota Endo.

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Ethics approval and consent to participate

All procedures involving human participants were in accordance with the Ethics Committee of Fukushima Medical University (Approval No. 2021-007) and the Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants.

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Not applicable.

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The authors declare that they have no competing interests.

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Supplementary Material 1

Appendix: The back-translation version of the Japanese WBIS

Appendix: The back-translation version of the Japanese WBIS

Question for screening survey participants.

How do you regard your own body weight?

1 = very underweight

2 = underweight

3 = slightly underweight

4 = average

5 = slightly overweight

6 = overweight

7 = very overweight

Only those participants who selected choices 5 through 7 were presented with the WBIS.


How do you feel about the following statements? Please select the appropriate response1 = strongly disagree

2 = disagree

3 = slightly disagree

4 = neither agree nor disagree

5 = slightly agree

6 = agree

7 = strongly agree

  1. 1.

    As someone who is overweight, I think that I am as capable as other people

  2. 2.

    As a result of my weight, I am less attractive than most people

  3. 3.

    I am very conscious of what other people think about me, so I feel anxious about being overweight

  4. 4.

    I wish I could dramatically change my weight

  5. 5.

    I get depressed when I think about being overweight

  6. 6.

    I am fed up with being overweight

  7. 7.

    My weight is an important factor in defining my value as a person

  8. 8.

    So long as I am overweight, I think that I don’t deserve to lead a truly fulfilling social life

  9. 9.

    I think it is fine to stay at my current weight

  10. 10.

    Due to being overweight, I don’t feel that I am my true self

  11. 11.

    Due to my weight, I don’t know how someone attractive could be interested in me

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Endo, S., Kasuga, H., Yusuke, M. et al. Reliability and validity of the Japanese version of the weight bias internalization scale. BMC Res Notes 15, 333 (2022).

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