In patients who have had a myocardial infarction or revascularization procedure, secondary prevention of coronary artery disease by comprehensive risk factor modification reduces mortality, decreases subsequent cardiac events, and improves quality of life.oronary artery disease (CAD) is the leading cause of death in the United States, with more than 1 million new and recurrent cardiovascular events occurring each year, and its prevalence and impact are expected to grow.
ratio level measurement the highest form of measurement that meets all the rules of other forms of measure; it includes mutually exclusive categories, exhaustive categories, rank ordering, equal spacing between intervals, and a continuum of values. Ratio level measurement also includes a value of zero.
The ratio scale of measurement is the most informative scale. It is an interval scale with the additional property that its zero position indicates the absence of the quantity being measured. You can think of a ratio scale as the three earlier scales rolled up in one. Like a nominal scale, it provides a name or category for each object (the numbers serve as labels). Like an ordinal scale, the objects are ordered (in terms of the ordering of the numbers). Like an interval scale, the same difference at two places on the scale has the same meaning. And in addition, the same ratio at two places on the scale also carries the same meaning.