Analysis of data obtained from discrete variables requires the use of specific statistical tests which are different from those used to assess continuous variables (such as cardiac output, blood pressure, or PaO 2) which can assume an infinite range of values.
Primary symptoms of dengue appear three to 15 days after the mosquito bite and include the following: 1  high fever and severe headache, 2  with severe pain behind the eyes that is apparent when trying to move the eyes.
1 Symptoms of Ebola virus disease occur suddenly up to 21 days after exposure and include fever, headache, sore throat, joint and muscle aches, and weakness, followed by diarrhea, vomiting, and stomach pain. 2  Some patients may bleed inside and outside the body.