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弗莱堡视力测试 (FrACT):最佳的试验数量?
1Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Germany, Freiburg, Germany. bach@uni-freiburg.de.
概括
确定视觉敏度需要精确度和努力的平衡. 对于8个替代任务,18个试验提供了一个高效的妥协,达到±0.17LogMAR的测试-重新测试精度.
科学领域:
- 眼科医生 眼科 眼科
- 心理物理学的精神物理.
- 视觉科学科学 视觉科学
背景情况:
- 视觉敏度评估涉及测量精度和参与者/考试人员的努力之间的权衡.
- 弗赖堡视力测试 (FrACT) 使用贝叶斯的"最佳PEST"算法来优化视型尺寸选择,以有效确定值.
研究的目的:
- 用FrACT确定最优的试验数量,以精确有效地测量视力敏度.
- 为了评估视力敏度测量在不同试验数量的测试-重新测试可靠性.
主要方法:
- 该研究使用2x78运行与26名参与者评估了测试-重新测试的协议限制 (LoA).
- 视力敏度从1.22到-0.59LogMAR不等,有些视力敏度是人为降低的.
- 分析了从6到48的试验计数的LoA.
主要成果:
- 随着越来越多的试验,协议限制 (LoA) 显著改善,从6次试验的±0.46 LogMAR下降到18次试验的±0.17 LogMAR.
- 随着试验的进一步增加,回报率逐渐下降,在48个试验中,LoA达到±0.12 LogMAR.
- 测试-重试精度在评估的视敏度范围内是一致的.
结论:
- 18个试验代表了准确性和参与者/考试人员负担之间的有效平衡,用于8个替代视力敏度任务.
- 这一发现适用于使用Landolt C定向的任务,可能也适用于Sloan信件.
- 较少的试验可能足以满足较少的响应替代方案的任务,例如翻转E (4个选择).
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