ORIGINAL ARTICLES Cross-cultural Adaptation and Validation of the French Version of the Diabetic Foot Self-care Questionnaire of the University of Malaga Irene Garcia-Paya, PhD* Yves Lescure, BP† Sebastian Delacroix, PhD† Gabriel Gijon-Nogueron, PhD* Methods: Cross-cultural adaptation was performed according to relevant international guidelines (International Society for Pharmacoeconomics and Outcomes Research), and the factor structure was determined. Internal consistency was measured using the Cronbach a. Item-total and inter-item correlations were assessed. Results: The French data set comprised 146 patients. The mean 6 SD patient age was 62.60 6 15.47 years. There were 47 women and 99 men. The structure matrix (with three factors) was tested by confirmatory factor analysis. The 16-item questionnaire had a Cronbach a of 0.92. The mean value for inter-item correlations was 0.48 (range, 0.17– 0.86). The rotated solution revealed a three-factor structure that accounted for 48.10% of the variance observed. A significant inverse correlation was observed between questionnaire scores and hemoglobin A 1c levels (r ¼ –0.17; P , .01). Conclusions: This study validates the French-language version of the DFSQ-UMA, which can be used as a self-reported outcome measure for French-speaking patients in France. (J Am Podiatr Med Assoc 109(5): 357-366, 2019) Foot ulcers affect 15% to 25% of patients with diabetes at some time in their lives, and the associated complications can have a severe effect on persons with this condition.1 In general, foot care education for people with diabetes is directed at patients with a history of complications, especially those with rising levels of hemoglobin A1c (HbA1c), and those who have had diabetes for several years.2 In addition, although many studies have focused on preventing ulcers and reducing the risk of amputation,3-6 very few have sought to determine the level of foot self-care in the *Department of Nursing and Podiatry, University of Malaga, Malaga, Spain. †Institut National de Podologie, Paris, France. Corresponding author: Gabriel Gijon-Nogueron, DPM, Department of Nursing and Podiatry, University of Malaga, Facultad de Ciencias de la Salud C/ Arquitecto Francisco Peñalosa 3 (Ampliación Campus Teatinos), Malaga 29071, Spain. (E-mail: gagijon@uma.es) population with diabetes mellitus.2,7-10 In most clinical guidelines, patient education and self-care are recommended to prevent complications of the diabetic foot.11 Patient-reported outcome questionnaires are commonly used in this context.12 However, there must be evidence to support the interpretation of the scores obtained by such instruments.13 Many instruments are available for evaluating care and self-care in diabetic patients, including the Neuropathy Total Symptom Score14 and the Social Support Scale for Self-care in Middle-Aged Patients with Type II Diabetes,15 but very few specifically address foot self-care, and even these combine questions about self-care with others regarding general care (eg, the Diabetic Foot Ulcer Scale16 and the Diabetic Foot Ulcer Scale–Short Form17). Currently available instruments that more specifically address foot self-care are inadequate in Journal of the American Podiatric Medical Association  Vol 109  No 5  September/October 2019 357 Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 Background: Diabetic foot care management is directed at patients with a history of complications, especially those with rising levels of hemoglobin A 1c, and those who have had diabetes for several years. The aim of this study was to cross-culturally adapt a French-language version of the Diabetic Foot Self-care Questionnaire of the University of Malaga (DFSQ-UMA) for use in France. various areas, such as having an excessive number of items18 or having undergone an incomplete or insufficiently rigorous validation process.8 On the other hand, a valid and reliable questionnaire to assess foot self-care by diabetic patients without amputation—the Diabetic Foot Self-care Questionnaire of the University of Malaga (DFSQUMA)19—has been proposed, but to date only the Spanish-language version has been validated. This study has two main aims: 1) to perform a cross-cultural adaptation of the DFSQ-UMA into French and 2) to determine the psychometric properties of the French-language version of the DFSQ-UMA (DFSQ-UMA-Fr). The study was approved by the medical research ethics committees of the University of Malaga (Spain) and Institute National de Podologie (France) and it was conducted in accordance with the provisions of the Declaration of Helsinki. All of the participants gave their signed consent. They were recruited at the Institute National de Podologie (Paris, France) and the following inclusion criteria were applied: age 18 years or older, diabetic, French mother tongue, and able to read, understand, and complete the questionnaire unaided. Cross-cultural Adaptation The cross-cultural adaptation process was conducted following the guidelines of the International Society for Pharmacoeconomics and Outcomes Research for the translation and validation of patient-reported outcome measures.20 The process took place in eight stages: 1) forward translation, 2) forward translation reconciliation, 3) back translation, 4) back translation review, 5) harmonization, 6) pilot testing/cognitive debriefing, 7) pilot testing/ cognitive debriefing review, and 8) proofreading. The process is summarized in Figure 1. Forward Translation. Two forward translations into French were performed from the original Spanish version of the DFSQ-UMA by two health professionals, working independently, who were native French speakers, residents of France, and fluent in both Spanish and French. Both translators based their translations on the International Society for Pharmacoeconomics and Outcomes Research guidelines. Forward Translation Reconciliation. The two forward translations were reconciled into a single version (draft 1) by the two original translators, 358      Complete the translated DFSQ-UMA and note the time needed to do so. Comment on the response options provided. Comment on any wording that was difficult to understand. Suggest alternative wording/phrasing for any wording that was difficult to understand. Describe in their own words what the wording meant to them. These responses were recorded verbatim and translated into Spanish. The five patients’ responses were summarized by the senior investigator. This summary also reflected the changes, recommendations, and suggestions indicated by the participants and the in-country investigators. Pilot Testing/Cognitive Debriefing Review. To improve the translated questionnaire, the pilot September/October 2019  Vol 109  No 5  Journal of the American Podiatric Medical Association Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 Methods together with a third, independent translator and with input from the project leader (G.G-N.). Back Translation. The reconciled French-language version (draft 1) was back translated into Spanish by two professional Spanish native translators resident in France, working independently. These translators had no previous knowledge of the DFSQ-UMA and were not given the original wording of the Spanish version of the DFSQ-UMA. Back Translation Review. The senior investigator, a native French speaker resident in Spain and fluent in both languages, reviewed the back translation for any discrepancies in meaning or terminology. Any problematic item was discussed until the discrepancies were resolved. This process resulted in a second draft of the French translation (draft 2). Harmonization. To produce the final French language translation, a harmonization meeting was held with the three French translators, the project leader, and the developer of the original DFSQ-UMA. During this meeting, any discrepancies or issues arising from the back translation were discussed, the translated version of the DFSQ-UMA was evaluated, and a final version was agreed on. Pilot Testing/Cognitive Debriefing. Once the translation process was completed, the translation was formatted to match the original version. The translated DFSQ-UMA was initially assessed for comprehensibility by five patient participants, who were French residents and native speakers, met the inclusion criteria, and had a low educational background without being illiterate. At this stage, each participant was asked by the in-country investigator to perform the following tasks: Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 Figure 1. Cross-cultural adaptation process. DFSQ-UMA, Diabetic Foot Self-care Questionnaire of the University of Malaga. (continued on next page) Journal of the American Podiatric Medical Association  Vol 109  No 5  September/October 2019 359 test results were reviewed by the in-country investigators. At this stage, any item that caused comprehension difficulties for more than 40% of the participants was reviewed, and any modifications suggested by the respondents were considered for incorporation in the final translated version. Proofreading. The project leader and another translator not involved in the initial translation process independently proofread the final formatted translation and discussed possible changes. Furthermore, the Flesch Reading Ease test and the Flesch-Kincaid Grade Level test were conducted to determine the readability of the text.21 The draft of the DFSQ-UMA, translated and 360 culturally adapted into French for France, was thus finalized and the cross-cultural validation phase begun to obtain the final draft. The following data for each participant were recorded: age, sex, occupational status, education level, and diabetesrelated diagnosis. Once the definitive items were designated, a scale with five options representing the adequacy of the patient’s self-care behavior was incorporated into the questionnaire: 1, very inadequate; 2, inadequate; 3, fair; 4, adequate; 5, very adequate. Exceptionally, for some items that explored the frequency of a particular self-care activity, the following scale was September/October 2019  Vol 109  No 5  Journal of the American Podiatric Medical Association Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 Figure 1. continued used: 1, never; 2, rarely; 3, sometimes; 4, often; 5, always (Fig. 2). Data Analysis Results Translation and Cross-cultural Adaptation Process The DFSQ-UMA was translated into French and then culturally adapted (Fig. 1). The resulting text was termed DFSQ-UMA-Fr (Fig 2). The pilot test revealed no discrepancies in meaning or terminology between the French and Spanish versions of the question- Figure 2. French questionnaire: the Diabetic Foot Self-care Questionnaire of the University of Malaga. naire. Moreover, the respondents did not request assistance in interpreting the questionnaire, and, therefore, no modification to the text was required. Evidence of Validity A total of 146 patients were included in this study, although one was excluded from the data analysis after failing to complete the questionnaire. Of these 146 respondents, 47 were women and 99 were men, with a mean 6 SD age of 62.60 6 15.47 years. The characteristics of the study sample are presented in Table 1. Journal of the American Podiatric Medical Association  Vol 109  No 5  September/October 2019 361 Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 For the descriptive statistics, means, standard deviations, and absolute and relative frequencies were calculated. The normality of the distributions was evaluated by the Kolmogorov-Smirnov test and by analysis of symmetry and kurtosis. Internal consistency was calculated using Cronbach a, for which a score of 0.70 to 0.95 was considered ‘‘good.’’22 Item-total and inter-item correlations were also assessed. Pearson correlations were calculated to assess the convergent validity between DFSQ-UMA and HbA1c level. Floor and ceiling effects were evaluated, taking values between 1% and 15% as optimal.23 To evaluate test-retest reliability, a subsample of patients (n ¼ 30) was asked to repeat the questionnaire. Kappa statistics with 95% confidence intervals (CIs) were computed to verify the level of interrater agreement concerning the different care categories (minimum, intermediate, semi-intensive, and intensive). Exploratory factor analysis was conducted, and the factor structure was determined using principal component analysis with nonorthogonal rotation (oblimin). The Kaiser-Meyer-Olkin test and the Bartlett test of sphericity were used to assess the appropriateness of the sample for the factor analysis. Eigenvalues greater than 1 and a scree plot were used to determine the number of factors. Factor loadings of 0.4 or greater were considered appropriate.10 Criterion validity was analyzed by parametric and nonparametric correlation coefficients between the questionnaire and HbA1c and glucose levels. This test was conducted because of the high risk of foot complications derived from HbA1c values greater than 7%24 and the relation between HbA1c levels and patient self-care. All of the statistical analyses were performed with IBM SPSS Software for Windows, Version 20.0 (IBM Corp, Armonk, New York). The mean 6 SD score for each item in the foot health questionnaire was 2.55 6 1.47 points. The highest mean 6 SD score (2.90 6 1.28) was obtained for the question Do you generally examine your foot yourself? and the lowest score (2.16 6 1.66) for Is it hard to find socks that are right for your feet? Table 2 shows the distribution of the scores. No ceiling/floor effect was detected. Reliability Analysis A Cronbach a of 0.922 was obtained, and the mean value for inter-item correlations was 0.48 (range, 0.17–0.86). Table 2 lists the distribution of scores and item-total correlations. The inter-item correlation matrix is detailed in Table 3. Interrater Reliability Two independent researchers each assessed the foot health of 15 patients using the questionnaire. The interrater levels of agreement ranged from kappa 0.84 (95% CI, 0.37–0.98) to 0.97 (95% CI, 0.93– 1.0), and the intraclass correlation ranged from 0.89 (95% CI, 0.78–0.94) to 0.92 (95% CI, 0.81–0.96) (Table 4). Men (n ¼ 99) Age (mean 6 SD [years]) 61.62 6 16.09 Duration of diabetes 13.28 6 10.23 (mean 6 SD [years]) Glucose (mean 6 SD [mg/dL]) 129.57 6 37.30 7.19 6 1.02 HbA1c (mean 6 SD [g/dL]) BMI (mean 6 SD) 27.02 6 6.34 Type of diabetes (No. [% by gender] Type I 8 (61.54) Type II non–insulin-dependent 20 (33.9) Type II insulin-dependent 34 (45.95) Educational level (No. [%]) Minimum 2 (28.57) Primary 20 (44.44) Secondary 29 (50.87) University 26 (70.27) ICC Women (n ¼ 47) ICC Total (N ¼ 146) 56.17–65.11 12.57–17.16 64.07 6 15.53 16.37 6 11.42 60.3–66.56 11.67–18.58 .02 .187 128.45–150.28 7.04–7.36 26.65–28.83 143.23 6 39.77 7.02 6 0.89 29.53 6 6.89 112.14–136.45 6.59–7.13 26.79–29.09 .470 .057 .640 5 (38.46) 39 (66.1) 40 (54.05) 13 59 74 5 (71.43) 25 (55.6) 38 (49.13) 11 (29.73) 7 45 67 37 P Value .368 .249 Abbreviations: BMI, body mass index; HbA1c, hemoglobin A1c; ICC, intraclass correlation coefficient. Table 2. Descriptive Scores and Reliability of Items Score (Mean 6 SD) Item 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. Do you generally examine your foot yourself? Do you look for sores and examine the state of the skin of your feet by yourself? Do you inspect your nails? How important do you consider personal care of your feet? Regarding the recommendations on how to take care of your own feet . . . To treat skin sores, dry skin patches, and calluses To dry your feet . . . Is it hard to find comfortable shoes for your feet? How often do your cut or treat your toenails? Is it hard for you to dry your feet after showering? Regarding socks ... Regarding conventional footwear, before using it . . . Is it hard to find socks that are right for your feet? Regarding new shoes . . . Regarding summer footwear, with excessive heat, . . . To warm your feet ... 362 2.9 2.7 2.67 2.59 2.49 2.37 2.49 2.64 2.87 2.25 2.16 2.68 2.7 2.44 2.6 2.6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 1.28 1.65 1.48 1.38 1.58 1.74 1.49 1.55 1.08 1.55 1.66 1.30 1.38 1.6 1.37 0.79 Corrected Item-Total Correlation Cronbach a if Item Deleted 0.471 0.559 0.619 0.754 0.83 0.731 0.763 0.581 0.267 0.781 0.769 0.646 0.41 0.712 0.716 0.382 0.921 0.919 0.917 0.914 0.911 0.914 0.913 0.918 0.925 0.912 0.912 0.917 0.923 0.914 0.915 0.925 September/October 2019  Vol 109  No 5  Journal of the American Podiatric Medical Association Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 Table 1. Characteristics of the 146 Study Patients Table 3. Inter-item Correlation Matrix Item No. Item 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 1 0.589 1 0.573 0.607 1 Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 1. Do you generally examine your foot yourself? 2. Do you look for sores and examine the state of the skin of your feet by yourself? 3. Do you inspect your nails? 4. How important do you consider personal care of your feet? 5. Regarding the recommendations on how to take care of your own feet . . . 6. To treat skin sores, dry skin patches, and calluses . . . 7. To dry your feet ... 8. Is it hard to find comfortable shoes for your feet? 9. How often do you cut or treat your toenails? 10. Is it hard for you to dry your feet after showering? 11. Regarding socks ... 12. Regarding conventional footwear, before using it . . . 13. Is it hard to find socks that are right for your feet? 14. Regarding new shoes . . . 15. Regarding summer footwear, with excessive heat, ... 16. To warm your feet ... 1. 0.529 0.508 0.596 1 0.406 0.49 0.31 0.594 0.746 1 0.351 0.46 0.64 0.701 1 0.387 0.492 0.518 0.667 0.666 0.675 1 0.233 0.419 0.367 0.375 0.611 0.461 0.492 1 0.155 0.407 0.284 0.279 0.224 0.188 0.169 0.173 1 0.159 0.315 0.343 0.533 0.714 0.756 0.661 0.629 0.164 1 0.256 0.394 0.402 0.523 0.66 0.741 0.703 0.623 0.12 0.385 0.26 0.418 0.5 0.393 0.554 0.61 0.203 0.297 0.183 0.321 0.32 0.857 1 0.342 0.138 0.508 0.428 1 0.141 0.276 0.176 0.094 0.34 0.273 0.459 1 0.314 0.327 0.411 0.546 0.638 0.557 0.569 0.401 0.198 0.623 0.652 0.585 0.359 1 0.137 0.298 0.348 0.528 0.646 0.557 0.651 0.477 0.179 0.742 0.687 0.542 0.41 0.657 1 0.225 0.108 0.261 0.273 0.253 0.339 0.212 0.115 0.037 0.372 0.298 0.442 0.409 0.344 0.306 Journal of the American Podiatric Medical Association  Vol 109  No 5  September/October 2019 1 363 Table 4. Factor Analysis Component Factor Is it hard for you to dry your feet after showering? To dry your feet . . . To treat skin sores, dry skin patches, and calluses . . . Regarding summer footwear, with excessive heat, . . . Regarding socks.. Regarding new shoes. . . Is it hard to find comfortable shoes for your feet? Regarding the recommendations on how to take care of your own feet . . . Do you generally examine your foot yourself? Do you inspect your nails? Do you look for sores and examine the state of the skin of your feet by yourself? How often do you cut or treat your toenails? How important do you consider personal care of your feet? To warm your feet ... Regarding conventional footwear, before using it . . . Is it hard to find socks that are right for your feet? Construct Validity (Factor Analysis) The Kaiser-Meyer-Olkin test result was 0.89, and the Bartlett test of sphericity was significant (P , .001). Therefore, the study sampling technique was assumed to be adequate. The rotated solution revealed a three-factor structure for the questionnaire, and these factors jointly accounted for 48.10% of the variance observed: factor 1, (items 5-8, 10, 11, 14, and 15), factor 2 (items 1-4 and 9), and factor 3 (items 12, 13, and 16.) Criterion Validity The correlation between questionnaire scores and HbA1c levels was significant and inverse (r ¼ –0.17; P , .01). Discussion This study provides evidence to support use of the DFSQ-UMA-Fr for French speakers, following the successful translation and cross-cultural adaptation of the original Spanish version. During the pilot study, the participants had no difficulty understanding the questionnaire, and the translated version obtained good results in the readability tests. Further evidence of its validity was provided by factor analysis and assessment of the criterion validity. In general, the results obtained for the psychometric performance of the DFSQ-UMA-Fr are similar to those of the Spanish version.19 The 364 2 3 0.897 0.721 0.783 0.766 0.881 0.636 0.703 0.727 0.784 0.75 0.81 0.511 0.581 0.767 0.663 0.758 DFSQ-UMA-Fr presents excellent internal consistency, with a Cronbach a score of 0.922. Because this is the first cross-cultural adaptation and validation of the DFSQ-UMA, it cannot be compared with other translations. It has been reported that HbA1c values greater than 7% constitute a risk factor for the development of foot ulcers,24 and, therefore, we hypothesize that patients with poorer self-care of the feet will tend to have elevated HbA1c values. Accordingly, the DFSQUMA-Fr could be used to help detect patients with risk factors for foot ulcers, although further research, with a larger sample, is needed to confirm this hypothesis. Almost 40% of the patients (n ¼ 57) who obtained a questionnaire result of less than 32 points, corresponding to inadequate or very deficient selfcare behavior,19 had HbA1c values of 7% or greater, although the difference is not statistically significant. In addition, these patients with a questionnaire score less than 32 points and HbA1c values greater than 7% may have lower levels of health-related quality of life.25 However, we lack questionnaire data with which to confirm or reject this possibility. Questionnaire items 1 (Do you generally examine your foot yourself?), 2 (Do you look for sores and examine the state of the skin of your feet by yourself?), and 9 (How often do your cut or treat your toenails?) received the highest mean scores and may also be those of greatest importance because one of the most dangerous complications of diabetes is the formation of foot ulcers,4 a condition that can lead to amputation and, in severe September/October 2019  Vol 109  No 5  Journal of the American Podiatric Medical Association Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 10. 7. 6. 15. 11. 14. 8. 5. 1. 3. 2. 9. 4. 16. 12. 13. 1 Conclusions This study validates the French-language version of the DFSQ-UMA, enabling its use as a self-reported outcome measure for French-speaking patients, both in clinical practice and in the research context. Financial Disclosure: None reported. Conflict of Interest: None reported. References 1. HINCHLIFFE RJ, VALK GD, APELQVIST J, ET AL: A systematic review of the effectiveness of interventions to enhance the healing of chronic ulcers of the foot in diabetes. Diabetes Metab Res Rev 24 (suppl 1): S119, 2008. 2. MCINNES A, JEFFCOATE W, VILEIKYTE L, ET AL: Foot care education in patients with diabetes at low risk of complications: a consensus statement. Diabet Med 28: 162, 2011. 3. BOULTON AJ, VILEIKYTE L, RAGNARSON-TENNVALL G, ET AL: The global burden of diabetic foot disease. Lancet 366: 1719, 2005. 4. CARMONA G, HOFFMEYER P, HERRMANN F, ET AL: Major lower limb amputations in the elderly observed over ten years: the role of diabetes and peripheral arterial disease. Diabetes Metab 31: 449, 2005. 5. FARD AS, ESMAELZADEH M, LARIJANI B: Assessment and treatment of diabetic foot ulcer. Int J Clin Pract 61: 1931, 2007. 6. SINGH N, ARMSTRONG DG, LIPSKY BA: Preventing foot ulcers in patients with diabetes. JAMA 293: 217, 2005. 7. BAUMGARTNER TA, CHUNG H: Confidence limits for intraclass reliability coefficients. Meas Phys Educ Exerc Sci 5: 179, 2001. 8. LINCOLN NB, RADFORD KA, GAME FL, ET AL: Education for secondary prevention of foot ulcers in people with diabetes: a randomised controlled trial. Diabetologia 51: 1954, 2008. 9. MCINNES A: No consensus between HCPs on diabetic foot. Diabet Foot J 31: 29, 2010. 10. NUNNALLY J, BERNSTEIN I: Psychometric Theory, 3rd Ed, McGraw-Hill, New York, 1994. 11. INTERNATIONAL WORKING GROUP ON THE DIABETIC FOOT: International Consensus on the Diabetic Foot. International Working Group on the Diabetic Foot, Maastricht, the Netherlands, 2007. 12. GIJON-NOGUERON G, NDOSI M, LUQUE-SUAREZ A, ET AL: Crosscultural adaptation and validation of the Manchester Foot Pain and Disability Index into Spanish. Qual Life Res 23: 571, 2014. 13. COOK DA, BECKMAN TJ: Current concepts in validity and reliability for psychometric instruments: theory and application. Am J Med 119: 166.e7, 2006. 14. BASTYR EJ, PRICE KL, BRIL V: Development and validity testing of the Neuropathy Total Symptom Score-6: questionnaire for the study of sensory symptoms of diabetic peripheral neuropathy. Clin Ther 27: 1278, 2005. 15. NADERIMAGHAM S, NIKNAMI S, ABOLHASSANI F, ET AL: Development and psychometric properties of a new Social Support Scale for Self-care in Middle-Aged Patients with Type II Diabetes (S4-MAD). BMC Public Health 12: 1035, 2012. 16. ABETZ L, SUTTON M, BRADY L, ET AL: The Diabetic Foot Ulcer Scale (DFS): a quality of life instrument for use in clinical trials. Pract Diabetes Int 19: 167, 2002. 17. BANN CM, FEHNEL SE, GAGNON DD: Development and validation of the Diabetic Foot Ulcer Scale-Short Form (DFS-SF). Pharmacoeconomics 21: 1277, 2003. 18. CHIN Y-F, Huang T-T: Development and validation of a diabetes foot self-care behavior scale. J Nurs Res 21: 19, 2013. 19. NAVARRO-FLORES E, MORALES-ASENCIO JM, CERVERA-MARÍN JA, ET AL: Development, validation and psychometric analysis of the diabetic foot self-care questionnaire of the University of Malaga, Spain (DFSQ-UMA). J Tissue Viability 24: 24, 2015. 20. WILD D, GROVE A, MARTIN M, ET AL: Principles of Good Practice for the Translation and Cultural Adaptation Process for Patient-Reported Outcomes (PRO) Measures: report of the ISPOR Task Force for Translation and Cultural Adaptation. Value Healh 8: 94, 2005. 21. LINNEY S: The Flesch reading ease and Flesch-Kincaid grade level. The Readable Blog, May 10, 2019. Available at: https://readable.com/blog/the-flesch-reading-ease- Journal of the American Podiatric Medical Association  Vol 109  No 5  September/October 2019 365 Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 cases, is associated with increased mortality.26 Therefore, correct self-care of the feet by patients with diabetes could help prevent the formation of ulcers and their consequences. This study has certain limitations. First, convenience sampling was used, with the patients being recruited exclusively from the National Institute of Podiatry (Paris, France). Nevertheless, although the sample was not prespecified to be explicitly representative, it did include patients of different ages, from different educational backgrounds, and with different types of employment status. Moreover, because the statistical analysis confirmed the validity of the DFSQ-UMA-Fr, the sampling approach is unlikely to have had a significant influence on the conclusions drawn. Because this study validates this French-language version of the DFSQ-UMA specifically for use in France, further cross-cultural validation would be required if the questionnaire were to be used in other Frenchspeaking countries, such as Canada or elsewhere. Finally, it should be acknowledged that the sample size is insufficient for a confirmatory analysis to be conducted to provide the results with more consistency. An increase in the sample size would be in line with the approach taken with the original DFSQ-UMA. and-flesch-kincaid-grade-level/. Accessed August 5, 2019. 22. TERWEE CB, BOT SDM, DE BOER MR, ET AL: Quality criteria were proposed for measurement properties of health status questionnaires. J Clin Epidemiol 60: 34, 2007. 23. MCHORNEY CA, TARLOV AR: Individual-patient monitoring in clinical practice: are available health status surveys adequate? Qual Life Res 4: 293, 1995. 24. GARCÍA-MORALES E, LÁZARO-MARTÍNEZ JL, MARTÍNEZ-HERNÁNDEZ D, ET AL: Impact of diabetic foot related complica- tions on the Health Related Quality of Life (HRQol) of patients: a regional study in Spain. Int J Low Extrem Wounds 10: 6, 2011. 25. RIBU L, HANESTAD BR, MOUM T, ET AL: Health-related quality of life among patients with diabetes and foot ulcers: association with demographic and clinical characteristics. J Diabetes Complications 21: 227, 2007. 26. VAN SCHIE CHM: A review of the biomechanics of the diabetic foot. Int J Low Extrem Wounds 4: 160, 2005. Downloaded from http://meridian.allenpress.com/japma/article-pdf/109/5/357/2458190/17-119.pdf by guest on 06 November 2021 366 September/October 2019  Vol 109  No 5  Journal of the American Podiatric Medical Association