Skip to main content
SpringerLink
Log in

Reliability, validity and responsiveness of the Italian version of the Foot Function Index in patients with foot and ankle diseases

  • Brief Communication
  • Published:
Quality of Life Research Aims and scope Submit manuscript

Abstract

Purpose

The purpose of this study was to translate the Foot Function Index (FFI) into Italian, to perform a cross-cultural adaptation and to evaluate the psychometric properties of the Italian version of FFI.

Methods

The Italian FFI was developed according to the recommended forward/backward translation protocol and evaluated in patients with foot and ankle diseases. Feasibility, reliability [intraclass correlation coefficient (ICC)], internal consistency [Cronbach’s alpha (CA)], construct validity (correlation with the SF-36 and a visual analogue scale (VAS) assessing for pain), responsiveness to surgery were assessed. The standardized effect size and standardized response mean were also evaluated.

Results

A total of 89 patients were recruited (mean age 51.8 ± 13.9 years, range 21–83). The Italian version of the FFI consisted in 18 items separated into a pain and disability subscales. CA value was 0.95 for both the subscales. The reproducibility was good with an ICC of 0.94 and 0.91 for pain and disability subscales, respectively. A strong correlation was found between the FFI and the scales of the SF-36 and the VAS with related content, particularly in the areas of physical function and pain was observed indicating good construct validity. After surgery, the mean FFI improved from 55.9 ± 24.8 to 32.4 ± 26.3 for the pain subscale and from 48.8 ± 28.8 to 24.9 ± 23.7 for the disability subscale (P < 0.01).

Conclusions

The Italian version of the FFI showed satisfactory psychometric properties in Italian patients with foot and ankle diseases. Further testing in different and larger samples is required in order to ensure the validity and reliability of this score.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3

References

  1. SooHoo, N. F., Shuler, M., Fleming, L. L., & American Orthopaedic Foot Ankle Society. (2003). Evaluation of the validity of the AOFAS clinical rating systems by correlation to the SF-36. Foot and Ankle International, 24(1), 50–55.

    PubMed  Google Scholar 

  2. Budiman-Mak, E., Conrad, K. J., & Roach, K. E. (1991). The Foot Function Index: A measure of foot pain and disability. Journal of Clinical Epidemiology, 44(6), 561–570.

    Article  CAS  PubMed  Google Scholar 

  3. Naal, F. D., Impellizzeri, F. M., Huber, M., & Rippstein, P. F. (2008). Cross-cultural adaptation and validation of the Foot Function Index for use in German-speaking patients with foot complaints. Foot and Ankle International, 29(12), 1222–1228.

    Article  PubMed  Google Scholar 

  4. Kuyvenhoven, M. M., Gorter, K. J., Zuithoff, P., Budiman-Mak, E., Conrad, K. J., & Post, M. W. (2002). The Foot Function Index with verbal rating scales (FFI-5pt): A clinimetric evaluation and comparison with the original FFI. Journal of Rheumatology, 29(5), 1023–1028.

    PubMed  Google Scholar 

  5. SooHoo, N. F., Vyas, R., & Samimi, D. (2006). Responsiveness of the Foot Function Index, AOFAS clinical rating systems, and SF-36 after foot and ankle surgery. Foot and Ankle International, 27(11), 930–934.

    PubMed  Google Scholar 

  6. Marinozzi, A., Martinelli, N., Panascì, M., Cancilleri, F., Franceschetti, E., Vincenzi, B., et al. (2009). Italian translation of the Manchester-Oxford Foot Questionnaire, with re-assessment of reliability and validity. Quality of Life Research, 18(7), 923–927.

    Article  PubMed  Google Scholar 

  7. Guillemin, F., Bombardier, C., & Beaton, D. (1993). Cross-cultural adaptation of health-related quality of life measures: Literature review and proposed guidelines. Journal of Clinical Epidemiology, 46(12), 1417–1432.

    Article  CAS  PubMed  Google Scholar 

  8. Apolone, G., & Mosconi, P. (1998). The Italian SF-36 Health Survey: translation, validation and norming. Journal of Clinical Epidemiology, 51(11), 1025–1036.

    Article  CAS  PubMed  Google Scholar 

  9. Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy. http://crc.marionegri.it/qdv/questionari/sf36/sf36v1ita.htm. Date last accessed February 2012.

  10. Cronbach, L. J. (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16(3), 297–334.

    Article  Google Scholar 

  11. Landis, J. R., & Koch, G. G. (1977). The measurement of observer agreement for categorical data. Biometrics, 33(1), 159–174.

    Article  CAS  PubMed  Google Scholar 

  12. Fleiss, J. L., & Shrout, P. E. (1977). The effects of measurement errors on some multivariate procedures. American Journal of Public Health, 67(12), 1188–1191.

    Article  CAS  PubMed  Google Scholar 

  13. Ravaud, P., Giraudeau, B., Auleley, G. R., Edouard-Noël, R., Dougados, M., & Chastang, C. (1999). Assessing smallest detectable change over time in continuous structural outcome measures: Application to radiological change in knee osteoarthritis. Journal of Clinical Epidemiology, 52(12), 1225–1230.

    Article  CAS  PubMed  Google Scholar 

  14. Bland, J. M., & Altman, D. G. (1986). Statistical methods for assessing agreement between two methods of clinical measurement. Lancet, 1(8476), 307–310.

    Article  CAS  PubMed  Google Scholar 

  15. Dawson, J., Doll, H., Coffey, J., Jenkinson, C., & Oxford and Birmingham Foot and Ankle Clinical Research Group. (2007). Responsiveness and minimally important change for the Manchester-Oxford Foot Questionnaire (MOXFQ) compared with AOFAS and SF-36 assessments following surgery for hallux valgus. Osteoarthritis and Cartilage, 15, 918–931.

    Article  CAS  PubMed  Google Scholar 

  16. McHorney, C. A., Ware, J. E., Lu, J. F., & Sherbournem, C. D. (1994). The MOS 36-item Short-Form Health Survey (SF-36): III. Tests of data quality, scaling assumptions, and reliability across diverse patient groups. Medical Care, 32(1), 40–66.

    Article  CAS  PubMed  Google Scholar 

  17. Husted, J. A., Cook, R. J., Farewell, V. T., & Gladman, D. D. (2000). Methods for assessing responsiveness: A critical review and recommendations. Journal of Clinical Epidemiology, 53(5), 459–468.

    Article  CAS  PubMed  Google Scholar 

  18. Agel, J., Beskin, J. L., Brage, M., Guyton, G. P., Kadel, N. J., Saltzman, C. L., et al. (2005). Reliability of the Foot Function Index: A report of the AOFAS Outcomes Committee. Foot and Ankle International, 26(11), 962–967.

    PubMed  Google Scholar 

  19. Saag, K. G., Saltzman, C. L., Brown, C. K., & Budiman-Mak, E. (1996). The Foot Function Index for measuring rheumatoid arthritis pain: Evaluating side-to-side reliability. Foot & Ankle International, 17(8), 506–510.

    Google Scholar 

  20. Budiman-Mak, E., Conrad, K. J., Stuck, R., & Matters, M. (2006). Theoretical model and Rasch analysis to develop a revised Foot Function Index. Foot and Ankle International, 27(7), 519–527.

    PubMed  Google Scholar 

Download references

Acknowledgments

We would like to thank Mrs. Anna Simonelli, Dr. Tommaso Arrischi, Dr. Andrea Facchinelli and Dr. Diego Dotari for their help in preparing this manuscript. We would like also to thank the anonymous reviewers for their valuable comments and suggestions.

Author information

Authors and Affiliations

  1. Department of Ankle and Foot Surgery, IRCCS Galeazzi, Galeazzi Hospital, Via R. Galeazzi, 20145, Milan, Italy

    Nicolò Martinelli, Gennaro Maria Scotto, Elena Sartorelli, Carlo Bonifacini, Alberto Bianchi & Francesco Malerba

Authors
  1. Nicolò Martinelli
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Gennaro Maria Scotto
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Elena Sartorelli
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Carlo Bonifacini
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Alberto Bianchi
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Francesco Malerba
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Nicolò Martinelli.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Martinelli, N., Scotto, G.M., Sartorelli, E. et al. Reliability, validity and responsiveness of the Italian version of the Foot Function Index in patients with foot and ankle diseases. Qual Life Res 23, 277–284 (2014). https://doi.org/10.1007/s11136-013-0435-4

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11136-013-0435-4

Keywords

Search

Navigation