NAFF Arabic Validation Study

Cross-cultural Adaptation and Validation of the Nottingham Assessment of Functional Footcare (NAFF) Questionnaire Among Arabic-speaking Adults With Diabetes in Tunisia

This study aims to evaluate a new Arabic version of the NAFF questionnaire, which measures foot care behaviors in adults with type 2 diabetes. Participants are adults with type 2 diabetes who will complete the questionnaire online. The study will assess how reliable and valid the Arabic version is, helping healthcare providers identify risky foot care behaviors and improve patient education.

Study Overview

• Status: Completed
• Conditions: Behavior; Self Care; Type 2 Diabetes Mellitus (T2DM); Questionnaire and Survey; Diabetic Foot Disease

Detailed Description

This study is a cross-sectional validation of the NAFF questionnaire translated into Arabic. Adult patients with type 2 diabetes will be recruited from endocrinology outpatient clinic in Sousse. Participants will complete the Arabic NAFF online. Primary outcomes include assessment of reliability (internal consistency, test-retest) and validity (construct and criterion validity). Secondary outcomes include the relationship between foot care behaviors and demographic or clinical factors. All participants will provide informed consent electronically. The study protocol was approved by the Ethics Committee of the Faculty of Medicine, Sousse. Data will be analyzed using descriptive and inferential statistics to evaluate the psychometric properties of the Arabic NAFF..

• Study Type: Observational
• Enrollment (Actual): 255

Contacts and Locations

Study Locations

• Tunisia
  • Sousse Governorate
    • Sousse, Sousse Governorate, Tunisia, 4000
      • Farhat Hached University Hospital, Endocrinology Department

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients with type 2 diabetes.

Description

Inclusion Criteria:

• Adults diagnosed with type 2 diabetes mellitus
• Age 26-65 years
• Ability to read and understand Arabic
• Receiving regular follow-up care at the endocrinology outpatient clinic

Exclusion Criteria:

• Cognitive impairments affecting comprehension or self-care activities
• Physical disabilities hindering self-care activities
• Presence of active foot ulcers at time of enrollment
• Bilateral lower-limb amputations

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Translation and adaptation	Translation, cultural adaptation, and assessment of content validity through expert panel evaluation using a 4-point relevance scale. Content validity index calculated by dividing items rated 3-4 by total items (n=29). Values ≥0.80 considered acceptable.	01/06/ 2021-31/07/ 2021 (2 months)
Descriptive data	Participants were asked to complete the NAFF-A questionnaire in the waiting room before clinical consultation. Demographic and clinical data were collected from medical records in collaboration with attending physicians, including gender, age, educational level, residence, diabetes duration, HbA1c levels, and history of ulceration or amputation.	01/08/2021 to 28/11/2021 (4 months)
Test-Retest Reliability of NAFF-A (Intraclass Correlation Coefficient)	Assessment of temporal stability of the NAFF-A using intraclass correlation coefficient (ICC) between test and retest administrations. Values ≥0.70 indicate good reliability, with higher values indicating better temporal stability.	Test-retest interval of 10-14 days between initial assessment and follow-up assessment.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Internal consistency	Assessment of internal consistency reliability of the Arabic version of the Nottingham Assessment of Functional Footcare questionnaire using Cronbach's alpha coefficient. Acceptable range is 0.70-0.95, with higher values indicating better internal consistency.	At the end of data collection
Criterion Validity - Correlation with Educational Level	Spearman's correlation coefficient between NAFF-A total scores and participant educational level (primary, secondary, university). Positive correlation expected based on literature showing higher education associated with better self-care behaviors.	At the end of data collection
Criterion Validity - Correlation with HbA1c Levels	Spearman's correlation coefficient between NAFF-A total scores and glycated hemoglobin (HbA1c) levels. Negative correlation expected as better foot care behaviors should be associated with better glycemic control.	At the end of data collection
Criterion Validity - Correlation with Ulceration Risk Stratification	Spearman's correlation coefficient between NAFF-A total scores and ulceration risk grades (0-3 scale based on IWGDF guidelines). Negative correlation expected as better foot care behaviors should be associated with lower ulceration risk.	At the end of data collection

Collaborators and Investigators

• Sponsor: Faculty of Medicine, Sousse

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2021
• Primary Completion (Actual): November 30, 2021
• Study Completion (Actual): November 30, 2021

Study Registration Dates

• First Submitted: August 29, 2025
• First Submitted That Met QC Criteria: December 5, 2025
• First Posted (Estimated): December 9, 2025

Study Record Updates

• Last Update Posted (Estimated): December 9, 2025
• Last Update Submitted That Met QC Criteria: December 5, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Nutritional and Metabolic Diseases; Diabetes Mellitus, Type 2; Behavior
• Other Study ID Numbers: NAFF-A

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared publicly due to ethical constraints and participant privacy protections as per the Ethics Committee approval (CEFMS 81/2021) and Tunisian data protection regulations. Aggregate data and statistical results are available through the published manuscript. Researchers interested in collaboration may contact the principal investigator to discuss potential data sharing arrangements that comply with ethical and regulatory requirements.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No