For example, many objects such as jar lids, screws, bolts, bottle caps, nuts, and more, need to be turned a specific direction to be tightened or loosened. Other usagesĪlthough the term clockwise originated with the use of clocks, it is also used in other areas. The rotation of the Earth is clockwise if viewed from above the South Pole, but counterclockwise if viewed from above the North Pole, where "above" means farther away from the center of the Earth. If there were someone else on the other side of the wall who could see the same rotation that we were looking at, from their perspective, a clockwise rotation for us would be counterclockwise for them.Īnother example is the rotation of the Earth. Another possible direction is a person standing on the other side of the wall. For example, looking straight at a clock on a wall is one possible direction. #CLOCKWISE VS COUNTERCLOCKWISE HOW TO#Refer to the time page to learn more about various aspects of time or about how to read an analog clock.īoth the terms clockwise and counterclockwise are defined based on looking at the clock from a specified direction. The opposite direction of motion is described with the term counterclockwise. In the image below, the arrows indicate a clockwise direction: With reference to the numbers on a clock, they are passed in order from least to greatest, starting from 12, which is the 0 position of a clock. Looking at a clock from the front or above, the hand of a clock moves right and around in a circular motion. The term clockwise describes the direction in which the hands of a clock move. In contrast, there was a negative association between counterclockwise rotation and stroke (HR, 0.77) and cardiovascular disease (HR, 0.81) in men and women, and total mortality (HR, 0.87) in women.Home / primary math / time / clockwise Clockwise Cox analysis found a positive association between clockwise rotation and heart failure, cardiovascular disease (HR, 1.28), and total mortality (HR, 1.15). Clockwise rotation was associated with higher rates of other mild ECG abnormalities, including axis deviation, ST depression, atrial fibrillation, T wave inversion, and minor Q waves. For both men and women, clockwise rotation increased in prevalence with age and was observed to have a lower prevalence in subjects with a midrange body mass index. In contrast, counterclockwise rotation was associated with lower rates of hypertension, stroke, cardiovascular disease, and death. In women, clockwise rotation was associated with a higher incidence of cardiovascular risk factors (hypertension, higher cholesterol, higher blood glucose levels), and higher rates of heart failure, cardiovascular disease, and death. In univariate analysis, counterclockwise rotation in men was associated with a higher prevalence of heart failure, cardiovascular disease, coronary heart disease, and total death, whereas counterclockwise rotation was associated with lower rates of cardiovascular disease and total death. A similar ratio was observed in subjects enrolled in NIPPON DATA in 1990. At baseline, 51.7% of subjects (48.4% of women, 56.0% of men) had normal rotation, 41.4% (45.8% of women, 35.8% of men) had counterclockwise rotation, and 6.9% (5.8% of women, 8.2% of men) had clockwise rotation. ECGs were analyzed by two independent observers in cases of disagreement between readers, a panel of epidemiologists and cardiologists determined the final coding. A complete dataset was available for 9067 subjects. Subjects in this analysis were enrolled in 1980, at which time they had a complete history and physical, laboratory evaluation, lifestyle questionnaire, and 12-lead ECG they were then followed until 2004. Individuals with a history of stroke or coronary heart disease were excluded from participation. The NIPPON DATA cohort invited >13,000 individuals in 300 health districts to participate in a longitudinal study. Nakamura and colleagues (2012) used the NIPPON DATA cohort to assess the prognostic value of clockwise and counterclockwise rotation. While long-recognized, the clinical significance if any of clockwise and counterclockwise rotation has not been well defined. “Counterclockwise rotation” refers to a variant in which the transition is “early,” occurring at or before lead V 3, whereas “clockwise rotation” is a variant in which the transition occurs late, at or after lead V 4. In a “normal” electrocardiogram (ECG), the transition of the QRS axis in the precordial leads occurs between leads V 3 and V 4 (i.e., there is a dominant S in V 3 and a dominant R in V 4).
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