Clinical Rheumatology

, Volume 29, Issue 5, pp 479–486 | Cite as

Reliability and validity of the Foot and Ankle Outcome Score: a validation study from Iran

  • Hossein Negahban
  • Masood Mazaheri
  • Mahyar Salavati
  • Soheil Mansour Sohani
  • Marjan Askari
  • Hossein Fanian
  • Mohamad Parnianpour
Original Article


The aims of this study were to culturally adapt and validate the Persian version of Foot and Ankle Outcome Score (FAOS) and present data on its psychometric properties for patients with different foot and ankle problems. The Persian version of FAOS was developed after a standard forward–backward translation and cultural adaptation process. The sample included 93 patients with foot and ankle disorders who were asked to complete two questionnaires: FAOS and Short-Form 36 Health Survey (SF-36). To determine test–retest reliability, 60 randomly chosen patients completed the FAOS again 2 to 6 days after the first administration. Test–retest reliability and internal consistency were assessed using intraclass correlation coefficient (ICC) and Cronbach’s alpha, respectively. To evaluate convergent and divergent validity of FAOS compared to similar and dissimilar concepts of SF-36, the Spearman’s rank correlation was used. Dimensionality was determined by assessing item–subscale correlation corrected for overlap. The results of test–retest reliability show that all the FAOS subscales have a very high ICC, ranging from 0.92 to 0.96. The minimum Cronbach’s alpha level of 0.70 was exceeded by most subscales. The Spearman’s correlation coefficient for convergent construct validity fell within 0.32 to 0.58 for the main hypotheses presented a priori between FAOS and SF-36 subscales. For dimensionality, the minimum Spearman’s correlation coefficient of 0.40 was exceeded by most items. In conclusion, the results of our study show that the Persian version of FAOS seems to be suitable for Iranian patients with various foot and ankle problems especially lateral ankle sprain. Future studies are needed to establish stronger psychometric properties for patients with different foot and ankle problems.


FAOS Persian version Reliability Validity 



This project was supported by a grant from the Postgraduate Studies and Research Program, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.


None of the authors have any financial or other interests relating to the manuscript to be submitted for publication in Clinical Rheumatology.


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Copyright information

© Clinical Rheumatology 2009

Authors and Affiliations

  • Hossein Negahban
    • 1
  • Masood Mazaheri
    • 2
  • Mahyar Salavati
    • 3
  • Soheil Mansour Sohani
    • 4
  • Marjan Askari
    • 5
  • Hossein Fanian
    • 6
  • Mohamad Parnianpour
    • 7
    • 8
  1. 1.Department of Physical Therapy, School of Rehabilitation SciencesAhvaz Jundishapur University of Medical SciencesAhvazIran
  2. 2.Musculoskeletal Research Center, School of Rehabilitation SciencesIsfahan University of Medical SciencesIsfahanIran
  3. 3.Department of Physical TherapyUniversity of Social Welfare and Rehabilitation SciencesTehranIran
  4. 4.Department of Physical Therapy, School of Rehabilitation SciencesIran University of Medical SciencesTehranIran
  5. 5.Department of Physical Therapy, School of Rehabilitation SciencesIsfahan University of Medical SciencesIsfahanIran
  6. 6.Department of Orthopedics, School of MedicineIsfahan University of Medical SciencesIsfahanIran
  7. 7.Department of Information and Industrial EngineeringHanyang UniversityAnsanRepublic of Korea
  8. 8.Biomechanics Laboratory, Department of Mechanical EngineeringSharif University of TechnologyTehranIran

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