NCT07004478

Turkish Adaptation Study of the Generic Functional Index

Turkish Adaptation, Validity and Reliability Study of the Generic Functional Index

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 200 (estimated)
• Sponsor: Istanbul Bilgi University · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Accepted

Summary

The Generic Functional Index is a scale developed to assess the general functional status of individuals. This study aims to evaluate the validity and reliability of the Turkish version of the Generic Functional Index. The adaptation process was designed to follow a standardized translation protocol, including forward translation, expert committee review, back-translation, pilot testing, and psychometric analyses. Data will be collected from individuals with musculoskeletal problems. Psychometric testing will include test-retest reliability, internal consistency, and construct validity analyses. The main hypotheses of this study are as follows: 1. The Turkish version of the Generic Functional Index will demonstrate high test-retest reliability when administered to individuals with musculoskeletal disorders. 2. The scores of the Turkish version of the Generic Functional Index will show a significant positive correlation with the scores of the Functional Independence Measure in individuals with musculoskeletal disorders.

Detailed description

Functional assessment is a fundamental component in evaluating the impact of health conditions on individuals' daily lives and in guiding rehabilitation strategies. The Generic Functional Index is a multidimensional instrument developed to assess overall functional status by capturing the effects of a person's problem on their daily activities, mobility, pain, and self-care performance. There is currently no validated Turkish version of the Generic Functional Index available for use in musculoskeletal populations. This study aims to translate and culturally adapt the Generic Functional Index into Turkish and to investigate its psychometric properties in individuals with musculoskeletal disorders. The adaptation will follow an internationally recognized translation methodology, including forward translation, synthesis, back-translation, expert committee review, and pre-testing. Psychometric evaluation will involve data collection from individuals with musculoskeletal conditions, with analyses focusing on internal consistency, test-retest reliability, and construct validity. Construct validity will be examined by analyzing the relationship between the Turkish Generic Functional Index and the Functional Independence Measure, which is a widely used tool for assessing independence in daily living activities. A strong correlation between these tools will support the convergent validity of the Turkish Generic Functional Index. This study is significant because a valid and reliable Turkish version of the Generic Functional Index will provide clinicians and researchers with a standardized tool for evaluating functional limitations in Turkish-speaking populations with musculoskeletal disorders. It will also contribute to the international applicability of the Generic Functional Indexby expanding its use to different cultural and linguistic contexts.

Conditions

• Musculoskeletal Diseases

Interventions

Type	Name	Description
OTHER	Translating the Generic Functional Index into Turkish and Related Processes	The translation process will follow a specific protocol in accordance with the guidelines. It will include two independent forward translations and one back-translation, conducted after obtaining written permission from the original authors. Discrepancies between translations will be reviewed by an expert committee to resolve terminological and cultural differences. The process will ensure conceptual and cultural equivalence between the original English version and the Turkish version. The final version of the questionnaire will be adapted to the target population and finalized in consultation with the original authors.
OTHER	Validity	Content validity will be calculated with the Content Validity Index, which is a result of expert opinions in terms of clarity, difficulty, and suitability of the Turkish version of the Generic Functional Index.
OTHER	Internal consistency and Reliability	The internal consistency of the items will be tested with Cronbach alpha. Test-retest reliability will be tested with intraclass correlation coefficient.

Timeline

• Start date: 2025-07-01
• Primary completion: 2026-05-01
• Completion: 2026-06-01
• First posted: 2025-06-04
• Last updated: 2026-01-06

Locations

1 site across 1 country: Turkey (Türkiye)