Construct and interpret a 99% confidence interval estimate of the mean difference. Increased blood vessel formulation is a predictive factor in survival for a certain disease. One treatment is stem cell transplantation with the patient's own stem cells. The accompanying data table represents the microvessel density for patients who had a complete response to the stem cell transplant. The measurements were taken immediately prior to the stem cell transplant and at the time the complete response was determined. Before 177 205 191 323 410 411 410 After 323 118 201 178 289 161 269 At the 0.01 level of significance