Management in the Emergency Department at Cedar Hill Hospital
has become increasingly concerned with the many preventable errors
and inefficiencies occurring in blood sample collection. The errors of
primary concern are mislabeled blood samples, hemolyzed blood
samples, and blood culture contaminations. In addition to raising
concerns about patient safety and satisfaction, these errors have
been found to increase costs by duplicating services, using extra
supplies, creating longer lengths of stay, and instigating unnecessary
a. An initial study of one hundred fifty samples found that the
incidence of mislabeling was 0.15 percent. How many
observations would it require to estimate the actual percentage of
mislabeling to within 0.1 percent, with confidence of 95.5 percent?
b. Initial results also found that the incidence of hemolysis was 13
How many observations would it require to estimate the
actual percentage of hemolysis to within 2 percent, with
confidence of 95.5 percent?