Comparative Efficacy of Duochrome Test Verse +1 Blur Test in Detecting Refracting Error Across Different Ages

NCT ID: NCT07001124

Last Updated: 2025-07-16

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 33 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-03-01
• Study Completion Date: 2026-02-28

Brief Summary

The comparative efficacy of the duochrome test versus +1 blur test in detecting refractive errors across different ages remains under-explored in current ophthalmic research. While the duochrome test is widely used to refine prescriptions, its standalone effectiveness compared to +1 blur test based refraction has not been thoroughly investigated.

Detailed Description

This study aims to evaluate the efficacy, accuracy, and reliability of the duochrome test in identifying refractive errors, including myopia and hyperopia across various ages. Refractive errors, including myopia, hyperopia, and astigmatism, are leading causes of visual impairment, requiring precise diagnostic tools. The duochrome test utilizes chromatic aberration to refine prescriptions, whereas the +1 blur test assesses spherical correction accuracy. Despite their clinical use, direct comparative studies remain limited. A total of 33 participants with estimated 10% dropout randomly assigned to undergo both tests. Groups will be based on different ages, Group A (18-35 years)and group B (36-60 years) ..both test (Duochrome test and +1 blur test) will apply on every patients.

Conditions

Refractive Errors

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: HEALTH_SERVICES_RESEARCH
• Blinding Strategy: NONE

Study Groups

duochrome test and +1 blur test (Group1) 18-35

Group Type: EXPERIMENTAL

duochrome test and +1 blur test

Intervention Type: DIAGNOSTIC_TEST

The participant is seated at a standard testing distance (typically 6 meters or 20 feet). A duochrome chart with black letters on a split red-green background is presented.

After determining the subjective refraction, a +1.00 diopter (DS) lens is added to the final prescription. The participant is asked to read the distance visual acuity (VA) chart. The expectation is that the visual acuity should drop to 4 lines on Snellen chart (6/24) when the +1.00 DS lens is added. If VA reduces to 6/24: Indicates that the refraction is not over-minused or over-plussed (proper end point of refraction). If VA remains better than 6/24: Suggests the patient was still accommodating, possibly leading to over-minus (in myopes) or under-plus (in hyperopes) and the refraction should be re-evaluated.

duochrome test and +1 blur test (Group1) 36-60

Group Type: ACTIVE_COMPARATOR

duochrome test and +1 blur test

Intervention Type: DIAGNOSTIC_TEST

The participant is seated at a standard testing distance (typically 6 meters or 20 feet). A duochrome chart with black letters on a split red-green background is presented.

After determining the subjective refraction, a +1.00 diopter (DS) lens is added to the final prescription. The participant is asked to read the distance visual acuity (VA) chart. The expectation is that the visual acuity should drop to 4 lines on Snellen chart (6/24) when the +1.00 DS lens is added. If VA reduces to 6/24: Indicates that the refraction is not over-minused or over-plussed (proper end point of refraction). If VA remains better than 6/24: Suggests the patient was still accommodating, possibly leading to over-minus (in myopes) or under-plus (in hyperopes) and the refraction should be re-evaluated.

Interventions

duochrome test and +1 blur test

The participant is seated at a standard testing distance (typically 6 meters or 20 feet). A duochrome chart with black letters on a split red-green background is presented.

After determining the subjective refraction, a +1.00 diopter (DS) lens is added to the final prescription. The participant is asked to read the distance visual acuity (VA) chart. The expectation is that the visual acuity should drop to 4 lines on Snellen chart (6/24) when the +1.00 DS lens is added. If VA reduces to 6/24: Indicates that the refraction is not over-minused or over-plussed (proper end point of refraction). If VA remains better than 6/24: Suggests the patient was still accommodating, possibly leading to over-minus (in myopes) or under-plus (in hyperopes) and the refraction should be re-evaluated.

Intervention Type: DIAGNOSTIC_TEST

Eligibility Criteria

Inclusion Criteria

• Age between 18 to 60 years old.
• Both genders.
• Those who have refractive error.
• Patients with no history of prior eye surgery.
• No active eye diseases affecting visual acuity, such as cataracts or retinal disorders.
• Ability to cooperate with both the duochrome test and +1 blur test.

Exclusion Criteria

• Patients with severe visual impairment or neurological conditions affecting vision.
• Patients with nystagmus or conditions that could interfere with reliable testing.
• Age below 18 year and above 60 year excluded
• Those patients who don't show their consent.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Superior University

OTHER

Sponsor Role: lead

Responsible Party

Muhammad Naveed Babur

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Eye professionals clinic (14-S DHA Phase 2 Ghazi road)

Lahore, Punjab Province, Pakistan

Countries

Pakistan

Other Identifiers

MSRSW/Batch-Fall23/821

Identifier Type: -

Identifier Source: org_study_id