Assessment of the light intensity of otoscopes utilized in teaching hospitals

ABSTRACT INTRODUCTION: To attain an accurate otoscopic diagnosis, a functioning device with adequate capacity must be used. OBJECTIVE: Evaluate the light intensity of otoscopes, comparing it utilizing the batteries present at the moment of calibration and after new batteries were supplied. METHODS: Cross-sectional study of a historical cohort, which assessed 38 otoscopes, measuring the light intensity with the batteries present at the moment of assessment compared to the intensity with new batteries, as well as charge of the test batteries and the new batteries. RESULTS: The mean of the sum of new batteries' charge was 3.19 V, and of the test batteries was 2.70 V, representing a decrease of 18.02% in charge. The mean luminosity with the new batteries was 366.89 lumens, whereas in the test batteries it was 188.32 lumens, representing a decrease of 83.75% in the light intensity. Student's t-test was applied for data comparison, showing a statistical difference between the light intensity with the original batteries and the new batteries (p = 0.0001; CI = 0.95). CONCLUSION: There was a statistically significant difference between the proportions of light intensity in the otoscopes. A small variation in battery charge results in a great variation in light.

引言：要获得准确的耳镜（otoscope）诊断，必须使用性能正常且具备足够供电能力的设备。
研究目的：评估耳镜的发光强度，并分别使用校准时搭载的原装电池与更换全新电池后的电池进行对比测量。
研究方法：本研究为历史性队列横断面研究，共纳入38台耳镜开展评估。分别测量原装电池供电时的发光强度，以及更换全新电池后的发光强度，同时检测测试用原装电池与全新电池的电压值。
研究结果：全新电池的总平均电压为3.19 V，原装测试电池的总平均电压为2.70 V，电压降幅达18.02%。全新电池供电时的平均发光强度为366.89 流明（lumens），原装电池供电时的平均发光强度为188.32 流明，二者发光强度降幅达83.75%。本研究采用Student t检验（Student's t-test）进行数据对比，结果显示原装电池与全新电池供电时的发光强度存在统计学差异（p=0.0001；置信区间CI=0.95）。
研究结论：耳镜使用原装电池与全新电池供电时的发光强度存在统计学显著性差异。电池电量的小幅变化，会导致发光强度产生大幅波动。