Temporomandibular Joint DisordersNCT07449221
Cross Cultural Adaptation, Reliability &Validity of The Arabic Version of 8_Item Jaw Functional Limitation Scale In Temporomandibular Joint Disorders
An observational study of Temporomandibular Joint Disorders, run by Cairo University at 1 site in Egypt.
Trial summary
The purpose of this study is to test if the translated Arabic version of the (jaw functional limitation scale -8) JFLS_8 , valid (face, content, feasibility) ,reliable (internal consistency, test retest) and culturally adapted enough to quantify the impact of temporomandibular joint (TMJ) disorders on jow function in… Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Temporomandibular Joint Disorders
- What is being tested?
- Questionnaire Administration
- How many people
- 100 participants
- Where
- 1 siteEgypt
- Study dates
- 7 Mar 2026to 15 May 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult male and female patients diagnosed with temporomandibular disorders (TMD), aged 18 to 65 years, who are native Arabic speakers. Participants are recruited from El-Kasr Elainy jaw and dental clinics to evaluate the validity, reliability, feasibility, and cultural adaptation of the Arabic version of the 8-item Jaw Functional Limitation Scale (JFLS-8).
Who may be able to join
- Patients aged 18 to 65 years .
- Diagnosis of temporomandibular disorders ) jaw pain-popping sounds in the jaw -limited jaw movements - orofacial pain ) for one month at least, not receiving actual treatment for the orofacial region (splinting)
- Being conscious and oriented.
- Able to read and write in Arabic.
- Both Genders were included.
Who cannot join
- History of trauma (recent head or neck or TMJ severe trauma)
- Recent surgery at the neck, head or TMJ
- Diagnosed systemic and psychiatric diseases; diseases that may affect the TMJ, such as ankylosing spondylitis or rheumatoid arthritis; and pregnancy
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Dina Sayed Abd Allah, PhD contact
Egypt1 site
El-Kasr Elainy jaw and dental clinics
Giza
Wafaa Hashem Ahmed Hasan, B.Sc, +20 10 50861450, wafaahashem859@gmail.com
About this study
The purpose of this study is to test if the translated Arabic version of the (jaw functional limitation scale -8) JFLS_8 , valid (face, content, feasibility) ,reliable (internal consistency, test retest) and culturally adapted enough to quantify the impact of temporomandibular joint (TMJ) disorders on jow function in arabic people or not?
Read the detailed description
Temporomandibular disorders (TMD) are relatively prevalent among adults, representing a considerable health concern. These disorders negatively affect psychological well-being and overall quality of life, highlighting the importance of accurate assessment and appropriate management strategies. Consequently, there is a growing need for reliable and efficient tools to assess functional limitations associated with TMD.
The Jaw Functional Limitation Scale with 8 items (JFLS-8) is a concise, valid, and reliable instrument used for the assessment of functional limitations related to the masticatory system. It was developed as a shorter version of the JFLS-20 and has been shown to be more practical for use in busy clinical settings while maintaining strong psychometric properties. The JFLS-8 has demonstrated excellent validity and reliability and has been successfully translated and culturally adapted into several languages, confirming its effectiveness as a clinical assessment tool.
Therefore, there is a clear need to translate the JFLS-8 into an Arabic version, perform cultural adaptation, and evaluate its validity and reliability among patients with temporomandibular disorders in Arabic-speaking populations.
- Conditions
- Temporomandibular Joint Disorders
- Being tested
- Questionnaire Administration
- Medical subject headings
- Temporomandibular Joint Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Questionnaire AdministrationOther
Participants complete the Arabic version of the 8-item Jaw Functional Limitation Scale (JFLS-8), along with reference measures (Visual Analogue Scale and Fonseca Anamnestic Index), to evaluate validity, reliability, feasibility, and cultural adaptation of the questionnaire.
A subset of participants completes the JFLS-8 again after 2 days to assess test-retest reliability.
What is being measured
The primary outcome is the main question the study is designed to answer.
Face Validity of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
It will be assessed using the Clarity Index and Expert Proportion of Clearance, judged by two expert panels (5 experts each) to evaluate whether the scale appears clear and relevant.
Measured: 30 minutes
Content Validity of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
It will be assessed using the Content Validity Index (CVI) and Expert Proportion of Relevance, to confirm that the 8 items adequately cover the construct of jaw functional limitation.
Measured: 30 minutes
Feasibility of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
It will be evaluated by two factors: time needed to complete the questionnaire and the missed item index (ratio of unanswered items).
Measured: 30 minutes
Internal Consistency Reliability of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
It will be measured using Cronbach's alpha to confirm that all 8 items are measuring the same underlying construct.
Measured: 30 minutes
Test-Retest Reliability of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
It will be assessed using Spearman's rank correlation coefficient, with a subset of patients completing the JFLS-8 again after 2 days under the same conditions.
Measured: 2 days
Secondary outcomes (2)
Visual Analogue Scale (VAS)
a 10 cm pain intensity scale measuring jaw pain during activity (recorded in cm), used to assess convergent validity with the JFLS-8.
Measured: 30 minutes
Fonseca Anamnestic Index (FAI)
a 10-item questionnaire classifying TMD severity (scores: 0-15 = no TMD; 20-40 = mild; 45-65 = moderate; 70-100 = severe), also used for convergent/construct validity testing.
Measured: 30 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Mar 2026
- Study start7 Mar 2026 (estimated)
- Primary completion7 May 2026 (estimated)
- Study completion15 May 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Temporomandibular Joint DisordersStudies of the same condition, open and under way.
- More trials run by Cairo UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Cairo University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Wafaa Hashem Ahmed Hasan, Cairo University
- Investigators
- Salwa Fadl Abdel Mageed, PhD, Study chair, Professor, Cairo UniversityDina Sayed Abd Allah, PhD, Study director, Lecturer, Cairo UniversityEman Sayed Ahmed Shalaby, PhD, Study director, Lecturer, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07449221
- Sponsor's protocol ID
- P.T.REC/012/006224
- Status last verified
- Feb 2026
- First submitted
- 27 Feb 2026
- Last updated
- 4 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Cross Cultural Adaptation, Reliability &Validity of The Arabic Version of 8_Item Jaw Functional Limitation Scale In Temporomandibular Joint Disorders
- ClinicalTrials.gov ID
- NCT07449221
- Acronym / sponsor ID
- P.T.REC/012/006224
- Conditions
- Temporomandibular Joint Disorders
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Cairo UniversityUniversity, hospital or other
- Study start
- 7 Mar 2026 (estimated)
- Primary completion
- 7 May 2026 (estimated)
- Study completion
- 15 May 2026 (estimated)
- First posted
- 4 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to test if the translated Arabic version of the (jaw functional limitation scale -8) JFLS_8 , valid (face, content, feasibility) ,reliable (internal consistency, test retest) and culturally adapted enough to quantify the impact of temporomandibular joint (TMJ) disorders on jow function in arabic people or not?
Detailed description
Temporomandibular disorders (TMD) are relatively prevalent among adults, representing a considerable health concern. These disorders negatively affect psychological well-being and overall quality of life, highlighting the importance of accurate assessment and appropriate management strategies. Consequently, there is a growing need for reliable and efficient tools to assess functional limitations associated with TMD.
The Jaw Functional Limitation Scale with 8 items (JFLS-8) is a concise, valid, and reliable instrument used for the assessment of functional limitations related to the masticatory system. It was developed as a shorter version of the JFLS-20 and has been shown to be more practical for use in busy clinical settings while maintaining strong psychometric properties. The JFLS-8 has demonstrated excellent validity and reliability and has been successfully translated and culturally adapted into several languages, confirming its effectiveness as a clinical assessment tool.
Therefore, there is a clear need to translate the JFLS-8 into an Arabic version, perform cultural adaptation, and evaluate its validity and reliability among patients with temporomandibular disorders in Arabic-speaking populations.
Study design
- Observational model
- Other
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult male and female patients diagnosed with temporomandibular disorders (TMD), aged 18 to 65 years, who are native Arabic speakers. Participants are recruited from El-Kasr Elainy jaw and dental clinics to evaluate the validity, reliability, feasibility, and cultural adaptation of the Arabic version of the 8-item Jaw Functional Limitation Scale (JFLS-8).
Key inclusion criteria (5 listed)
- Patients aged 18 to 65 years .
- Diagnosis of temporomandibular disorders ) jaw pain-popping sounds in the jaw -limited jaw movements - orofacial pain ) for one month at least, not receiving actual treatment for the orofacial region (splinting)
- Being conscious and oriented.
- Able to read and write in Arabic.
- Both Genders were included.
Key exclusion criteria (3 listed)
- History of trauma (recent head or neck or TMJ severe trauma)
- Recent surgery at the neck, head or TMJ
- Diagnosed systemic and psychiatric diseases; diseases that may affect the TMJ, such as ankylosing spondylitis or rheumatoid arthritis; and pregnancy
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Questionnaire AdministrationParticipants complete the Arabic version of the 8-item Jaw Functional Limitation Scale (JFLS-8), along with reference measures (Visual Analogue Scale and Fonseca Anamnestic Index), to evaluate validity, reliability, feasibility, and cultural adaptation of the questionnaire. A subset of participants completes the JFLS-8 again after 2 days to assess test-retest reliability. | Other | – |
Primary outcome
Face Validity of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
Time frame: 30 minutes
It will be assessed using the Clarity Index and Expert Proportion of Clearance, judged by two expert panels (5 experts each) to evaluate whether the scale appears clear and relevant.
Content Validity of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
Time frame: 30 minutes
It will be assessed using the Content Validity Index (CVI) and Expert Proportion of Relevance, to confirm that the 8 items adequately cover the construct of jaw functional limitation.
Feasibility of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
Time frame: 30 minutes
It will be evaluated by two factors: time needed to complete the questionnaire and the missed item index (ratio of unanswered items).
Internal Consistency Reliability of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
Time frame: 30 minutes
It will be measured using Cronbach's alpha to confirm that all 8 items are measuring the same underlying construct.
Test-Retest Reliability of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8)
Time frame: 2 days
It will be assessed using Spearman's rank correlation coefficient, with a subset of patients completing the JFLS-8 again after 2 days under the same conditions.
2 secondary outcomes
Visual Analogue Scale (VAS)
Time frame: 30 minutes
Fonseca Anamnestic Index (FAI)
Time frame: 30 minutes
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Mar 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Dina Sayed Abd Allah, PhD contact
Salwa Fadl Abdel Mageed, PhD study chair
Professor, Cairo University
Dina Sayed Abd Allah, PhD study director
Lecturer, Cairo University
Eman Sayed Ahmed Shalaby, PhD study director
Lecturer, Cairo University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Temporomandibular Joint Disorders, run by Cairo University at 1 site in Egypt.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 4 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Egypt. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Wafaa Hashem Ahmed Hasan, B.Sc (+20 10 50861450, wafaahashem859@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Face Validity of the Arabic Version of the 8-item Jaw Functional Limitation Scale (JFLS-8) (time frame: 30 minutes). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Mar 2026.