Hatch Brian C, Hilber David J, Elledge James B, Stout James W, Lee Robyn B
Tri-Service Vision Conservation and Readiness Program, U.S. Army Center for Health Promotion and Preventive Medicine, Aberdeen Proving Ground/EA, Maryland, USA.
Optom Vis Sci. 2009 Dec;86(12):E1359-67. doi: 10.1097/OPX.0b013e3181be9740.
To explore the effects of visual acuity on target discrimination and marksmanship.
A randomized, single-blind, repeated measures study was conducted to evaluate the effect of visual acuity on target discrimination and marksmanship. Subjects were examined for inclusion criteria and equivalent plus lens over-refractions necessary to obtain the five test visual acuity ranges. Qualified subjects fired at randomized target presentations from 50 to 300 m while wearing customized spectacles to yield the visual acuity levels being evaluated. Subjects then rotated foxholes for target discrimination sequences. Randomized targets marked as friend or enemy were presented in like manner for each of the five visual acuity levels.
Subjects at acuities better than 0.2 LogMAR were significantly more likely to hit the target than those with acuities equal to or worse than 0.7 LogMAR. Target discrimination results show subjects with acuities between -0.2 and 0.6 LogMAR were significantly more likely to correctly identify the target than those with acuities equal to or worse than 0.7 LogMAR. In addition, those at acuities of 0.0 LogMAR or better performed significantly better than those with acuities between 0.3 and 0.6 LogMAR.
Visual acuity significantly affects target discrimination and marksmanship performance. Results of this study closely mirror expected findings based on visual angles with acuities in the range 0.3 to 0.4 LogMAR (20/40-20/50) being the transition zone where performance begins to deteriorate. This performance-based evidence fully supports a vision classification system that mandates eyewear to maximize visual performance for deployable military members. Based on the results of this study, the current U.S. Army, U.S. Navy, and U.S. Marine Corps vision readiness standards of 20/40 or better uncorrected or corrected vision seems to be a valid choice because it is the transition point for performance in both target discrimination and marksmanship ability.
探讨视力对目标识别和射击技能的影响。
进行了一项随机、单盲、重复测量研究，以评估视力对目标识别和射击技能的影响。检查受试者的纳入标准以及获得五个测试视力范围所需的等效正透镜过矫。合格受试者在佩戴定制眼镜以产生所评估的视力水平的情况下，从50米至300米对随机呈现的目标进行射击。然后，受试者转动散兵坑进行目标识别序列测试。对于五个视力水平中的每一个，以类似方式呈现标记为友方或敌方的随机目标。
视力优于0.2 LogMAR的受试者比视力等于或差于0.7 LogMAR的受试者更有可能击中目标。目标识别结果显示，视力在-0.2至0.6 LogMAR之间的受试者比视力等于或差于0.7 LogMAR的受试者更有可能正确识别目标。此外，视力为0.0 LogMAR或更好的受试者的表现明显优于视力在0.3至0.6 LogMAR之间的受试者。
视力显著影响目标识别和射击技能表现。本研究结果与基于视角的预期结果密切相符，视力在0.3至0.4 LogMAR（20/40 - 20/50）范围内是性能开始下降的过渡区。这种基于性能的证据充分支持了一项视力分类系统，该系统要求佩戴眼镜以最大限度提高可部署军事人员的视觉性能。基于本研究结果，美国陆军、海军和海军陆战队目前的视力准备标准，即未矫正或矫正视力达到20/40或更好，似乎是一个有效的选择，因为它是目标识别和射击技能表现的过渡点。
