Translation, Cross-cultural Adaptation, and Validation of the FPI-6 in Spain (FPI-6-ES)

May 9, 2026 updated by: Paloma López Ros

Translation, Cross-cultural Adaptation, and Validation of the Foot Posture Index (FPI-6) in Spain

The objective of this study is to translate, cross-culturally adapt, and validate the Spanish version of the Foot Posture Index (FPI-6). This clinical tool is widely used to evaluate standing foot posture through six visual criteria. The study aims to provide Spanish-speaking clinicians and researchers with a reliable and valid instrument to assess foot posture in the Spanish population, ensuring that the psychometric properties of the original scale are preserved

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

This study follows a prospective, observational design and will be carried out in two phases:

Phase 1: Translation and Cross-Cultural Adaptation. Following international standards (forward-backward translation method), the original English FPI-6 will be translated into Spanish by two independent translators. A synthesis version will be created, followed by a back-translation into English to ensure conceptual equivalence. A pilot test will be conducted to ensure the clarity of the items.

Phase 2: Validation and Psychometric Evaluation. The Spanish version of the FPI-6 will be administered to a sample of participants. To evaluate reliability, intra-rater and inter-rater reliability will be calculated using the Intraclass Correlation Coefficient (ICC). Internal consistency will be assessed using Cronbach's alpha. Construct validity will be analyzed by comparing FPI-6 scores with other validated clinical measures of foot posture

Study Type

Observational

Enrollment (Estimated)

100

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Paloma López Ros, PhD
  • Phone Number: +34656928127
  • Email: plopez@umh.es

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

The study population consists of individuals from the general population in Spain, covering a wide age range that includes children (from 6 years old), adults, and the elderly (up to 89 years). Participants are recruited through convenience sampling from university clinics and local community centers to ensure a diverse representation of foot types (neutral, pronated, and supinated) across different stages of life

Description

Inclusion Criteria:

  • Participants aged between 6 and 89 years
  • Ability to understand and sign the informed consent form. In the case of minors, written informed consent from parents or legal guardians and child's assent (where applicable) are required
  • Ability to maintain a relaxed standing position unassisted for the duration of the clinical assessment

Exclusion Criteria:

  • History of major surgery or significant trauma in the lower limbs or feet.
  • Presence of open wounds or active skin infections on the feet at the time of the examination.
  • Neurological or musculoskeletal conditions that severely affect balance or standing posture.
  • Cognitive impairment that prevents the participant from following simple clinical instructions

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
General Population (Children and Adults)
This group includes participants of all ages, including children (from 5 years old) and adults. The study aims to evaluate the psychometric properties of the Spanish version of the Foot Posture Index (FPI-6) across a diverse age range to ensure its validity and reliability in the general Spanish-speaking population
Other: Spanish version of the Foot Posture Index (FPI-6)
The assessment consists of the clinical application of the Spanish version of the Foot Posture Index (FPI-6). This is a non-invasive observational method where the investigator evaluates six specific criteria of the foot while the participant stands in a relaxed position. The six criteria include: talar head palpation, supra and infra-malleolar curvature, calcaneal frontal plane position, prominence in the region of the talonavicular joint, congruence of the internal longitudinal arch, and abduction/adduction of the forefoot on the rearfoot. Each item is scored between -2 and +2, providing a total score between -12 and +12
Other: Spanish version of the Foot Posture Index (FPI-6)
Clinical assessment of standing foot posture using the Spanish translation of the Foot Posture Index (FPI-6). This tool evaluates six criteria: talar head palpation, supra and infra-malleolar curvature, calcaneal frontal plane position, prominence in the region of the talonavicular joint, congruence of the internal longitudinal arch, and abduction/adduction of the forefoot on the rearfoot. Each item is scored on a scale from -2 to +2. The tool will be applied to a sample of children (from 5 years old) and adults to evaluate its psychometric properties, including reliability and internal consistency

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Intra-rater and Inter-rater Reliability of the Spanish FPI-6
Time Frame: Baseline and 7-14 days later
Consistency of the Foot Posture Index (FPI-6) scores evaluated through the Intraclass Correlation Coefficient (ICC). Intra-rater reliability will be assessed by one examiner repeating the test after 1-2 weeks. Inter-rater reliability will be assessed by two examiners evaluating each subject with a one-hour interval.
Baseline and 7-14 days later
Internal Consistency of the Spanish FPI-6
Time Frame: At Baseline (Day 1)
Measured using Cronbach's alpha to ensure that all six items of the FPI-6 contribute coherently to the total score. A value > 0.70 is expected.
At Baseline (Day 1)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Criterion Validity
Time Frame: At Baseline (Day 1)
Correlation of the Spanish FPI-6 total score with the Foot Function Index (FFI) and the American Orthopaedic Foot and Ankle Society (AOFAS) scale using Spearman's correlation
At Baseline (Day 1)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Paloma López Ros

Investigators

  • Principal Investigator: Jonatan García-Campos, PhD, Universidad Miguel Hernández
  • Principal Investigator: Javier Marco-Lledó, PhD, Universidad Miguel Hernández
  • Principal Investigator: Vicenta Martínez-Córcoles, PhD, Universidad Miguel Hernández
  • Principal Investigator: Roberto Pascual-Gutiérrez, MSc, Universidad Miguel Hernández
  • Principal Investigator: Laura Tabernero-Grau, MSc, Universidad Miguel Hernández
  • Principal Investigator: David Montoro-Cremades, MSc, Universidad Miguel Hernández
  • Study Director: Paloma López Ros, PhD, Universidad Miguel Hernández

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

May 16, 2026

Primary Completion (Estimated)

May 1, 2028

Study Completion (Estimated)

May 1, 2028

Study Registration Dates

First Submitted

May 9, 2026

First Submitted That Met QC Criteria

May 9, 2026

First Posted (Actual)

May 15, 2026

Study Record Updates

Last Update Posted (Actual)

May 15, 2026

Last Update Submitted That Met QC Criteria

May 9, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • DCC.PLR.260209

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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