Biostatistics is an innovative field that involves the design, analysis, and interpretation of data as applied to biological areas. Biological laboratory experiments, medical research (including clinical research) and health services. Biostatistics experts arrive at conclusions about disease and health risks by evaluating and applying mathematical and statistical formulas to the factors that impact health.

The types of epidemiological studies are represented in the figure.

For the evaluation of diagnostic tests, we can see in the figure how to calculate the value of sensibility, specificity, the positive predictive value and the negative predictive value.

Other tests can be made like the calculation of positive or negative likelihood ratio. It calculates the ratio between a probability the test is positive/negative that has the disease, and the probability the test is negative/positive that has not the disease.

This are some fundamental ideas and basic concepts for who want to learn and have an introduction in this field of statistics.