Normal binocular single vision range in Singaporean adults
Pilot Study of Normative Range of Field of Binocular Single Vision in Adults in Singapore
This study will test the normal range of binocular single vision in healthy Singaporean adults of Asian descent aged 21 to 59.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 30 (estimated) |
| Ages | 21 Years to 59 Years |
| Sex | All |
| Sponsor | Tan Tock Seng Hospital Academic / other |
| Locations | 1 site (Singapore, Singapore) |
| Trial ID | NCT07257341 on ClinicalTrials.gov |
What this trial studies
This observational project will measure the field of binocular single vision in adults aged 21–59 who are of Asian descent and meet strict ocular and systemic health criteria. Participants will undergo standardized binocular field testing at Tan Tock Seng Hospital using modern measurement techniques and language support in English, Mandarin, or Bahasa Melayu. Collected data will be used to create up-to-date, population-specific normative boundaries and to compare those boundaries with the historical Feibel & Roper-Hall values from 1974. The goal is to address limitations of the original small, demographically narrow dataset by providing more representative norms for clinical use in Singapore.
Who should consider this trial
Good fit: Healthy adults of Asian descent aged 21–59 who can understand English, Mandarin, or Bahasa Melayu, have adequate near vision, no history of ocular/facial/head trauma or ocular disease, and can give informed consent.
Not a fit: People with prior ocular disease or surgery, facial or head trauma, systemic conditions affecting vision, poor unaided near vision, significant ocular misalignment, or inability to attend in person or communicate in the listed languages are unlikely to benefit.
Why it matters
Potential benefit: If successful, the results could provide clinicians with updated, population-specific norms to improve diagnosis and management of binocular vision problems in Singapore.
How similar studies have performed: The method follows the longstanding Feibel & Roper-Hall normative approach from 1974, but comparable large-scale contemporary normative studies in Asian populations are limited or lacking.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age: 21 to 59 years old * Gender: Males or females * Ethnicity: Asian descent. * Language comprehension: Able to understand verbal spoken instructions in: • British/American English * Mandarin Chinese * Bahasa Melayu * Protocol compliance: Ability to comply with the study protocol, as determined by the investigator's judgment * Consent capacity: Must be able to understand and provide informed consent, with signed informed consent form required before any study assessments Exclusion Criteria: \- Communication barrier: Unable to understand verbal spoken instructions * Medical history: * Any facial trauma * Any ocular trauma * Any head trauma * Any history of ocular disease * Any history of ocular surgery * Systemic condition(s) * Near visual acuity: o Right eye \& Left eye monocularly, binocularly unaided near vision: worse than N6 at 40cm from participant's nose * Ocular alignment: o Prism cover test at near (30cm) of equal or greater than 10 prism diopters at these positions of gaze: * Primary gaze * Right gaze * Left gaze * Up gaze * Down gaze * Extraocular movement: o Extraocular movement of over-action or under-action of equal or greater than 0.5 in any of the nine cardinal positions of gaze * Confrontational Visual field: o Abnormal monocular visual field on confrontational visual field test * Hess chart test o Abnormal or asymmetry in pattern of extraocular muscle action in Hess chart test
Where this trial is running
Singapore, Singapore
- Tan Tock Seng Hospital — Singapore, Singapore, Singapore (Recruiting)
Study contacts
- Principal investigator: Daniel Chin, MBBS — Tan Tock Seng Hospital
- Study coordinator: Zheng Kuang Noel Soh, BSc
- Email: zheng.kuang.soh@nhghealth.com.sg
- Phone: +65 6357 3693
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.