During a trial-frame refraction, what sequence was used to test the spherical power in the example?

During a trial-frame refraction, what sequence was used to test the spherical power in the example?

• A. Show +1.00 first, then -1.00
• B. Show -1.00 first, then +1.00
• C. Show +0.50 first, then +0.50
• D. Show Plano first, then +1.00

Answer: (A)

During a trial-frame refraction, you want to minimize the influence of accommodation on the response. The way to do that is to fog the eye first with a plus lens, which relaxes the eye’s focusing and makes the subjective response more about the refractive error itself rather than ongoing accommodation. In the example, the examiner starts with a plus lens of +1.00 to introduce this mild fog, then compares it with minus power by presenting -1.00. This sequence quickly reveals which spherical correction the patient truly prefers: if acuity is better with the plus, the eye is effectively more hyperopic or less myopic; if acuity improves with the minus, the spherical diagnosis leans toward myopia and the minus helps pinpoint the correct amount. Using plus first helps prevent accommodation from biasing the result and makes the refinement step with minus more efficient.

During a trial-frame refraction, you want to minimize the influence of accommodation on the response. The way to do that is to fog the eye first with a plus lens, which relaxes the eye’s focusing and makes the subjective response more about the refractive error itself rather than ongoing accommodation. In the example, the examiner starts with a plus lens of +1.00 to introduce this mild fog, then compares it with minus power by presenting -1.00. This sequence quickly reveals which spherical correction the patient truly prefers: if acuity is better with the plus, the eye is effectively more hyperopic or less myopic; if acuity improves with the minus, the spherical diagnosis leans toward myopia and the minus helps pinpoint the correct amount. Using plus first helps prevent accommodation from biasing the result and makes the refinement step with minus more efficient.