Bio Statistics

BIOSTATISTICS Definition Biostatistics is the collection, arrangement, analysis and interpretation of mathematical facts or data with special reference to studies of Health and Social Problems IMPORTANCE • Used in Research • Assess results of Clinical Trials •

Assess new treatment strategies; new drugs

•

To find the cause of a certain disease or condition

CLINICAL TRIALS IN PHARMACOLOGY THESE ARE USED TO TEST THE EFFECTIVENESS OR OTHER CHARACTERISTICS OF A DRUG FOR A PARTICULAR CONDITION ALSO A NEW TREATMENT (DRUG) MAY BE COMPARED WITH AN OLD TREATMENT (DRUG) IMPORTANT TERMINOLOGY IN CLINICAL TRIALS SAMPLES (TEST AND CONTROL) SAMPLE SIZE VARIABLE(S) CONSENT PLACEBO PROSPECTIVE STUDY RETROSPECTIVE STUDY BIAS SINGLE BLINDED STUDY DOUBLE BLINDED STUDY

PRESENTATION OF DATA A.PICTORIAL DESCRIPTION •

BAR GRAPHS, HISTOGRAMS

• FREQUENCY TABLES •

PIE CHARTS, PICTOGRAMS

B.QUANTITATIVE DESCRIPTION

MEASURES OF CENTRAL TENDENCY 1. MEAN (AVERAGE) SUM OF ALL THE READINGS DIVIDED BY THE NUMBER OF READINGS MEAN = SUM OF ALL INDIVIDUAL BSERVATIONS NUMBER OF OBSERVATIONS M=ΣX n Σ = SUM OF X= INDIVIDUAL OBSERVATIONS n = NUMBER OF OBSERVATIONS

MEASURES OF VARIABILITY

−3σ

−2σ

Mean 95.5 % 99.7 %

+2σ

+3σ