INTRODUCTION Statistical methods for evaluating medication safety data differ depending on the stage of the drug's life cycle. DURING CLINICAL TRIALS POST-MARKETING SURVEILLANCE 🐭Descriptive Statistics. 🐭Hypothesis Testing 🐭Time-to-event analysis 🐭Regression Analysis 👩🏻🔬Disproportionality Analysis 👩🏻🔬Bayesian Methods
DURING CLINICAL TRIALS
DESCRIPTIVE STATISTICS 🌀Side effect Reports = 100 patients Headache 20% (20 patients) Diarrhoea 15% (15 patients) Dizziness10% (10 patients) Nausea5% (5 patients) Most common: Headache 🌀Age of patients with dizziness Mean value= 54.6 years Median value= 55 years Mean value Average Median value Middle value 🌀Range of years: 62-45=17 years Range:17 years Age spread: 17 years Descriptive statistics provide a simple, initial understanding of a drug’s safety profile
HYPOTHESIS TESTING STEP-1: FORMULATE HYPOTHESIS NULL HYPOTHESIS(H ): Drug X Adverse event ALTERNATIVE HYPOTHESIS(H a ): Drug X Adverse event STEP-2: COLLECT DATA & CALCULATE Clinical Trial Data Statistical Test (e.g. Chi-square test) GROUP PATIENTS ADVERSE EVENT Drug X 1000 50 (5%) Placebo 1000 20(2%) P-value=0.05 P-value <0.05 Adverse event is produced by the drug P-value >0.05 Adverse event is not produced by the drug
CHI-SQUARED TEST
CONTD..
CONTD.. Ho Drug A does not cause headache
TIME-TO-EVENT ANALYSIS Kaplan-Meier Curve ⏰Time-to-event analysis is also known as survival analysis ⏰Represented by Kaplan-Meier curve ⏰GOAL: To estimate the probability of survival (free from adverse effects) ⏰Y-AXIS: Cumulative probability of being event free defines the dependent variable and its scale ⏰Median Survival time is employed; Time where the curve crosses 50% survival probability line
Drug dose (mg) Adverse Event Occurrence Regression line quantifies the linear association between drug dose and adverse event occurrence REGRESSION ANALYSIS 🌸Regression analysis draws a line through the data points to show the overall trend. This line helps predict how likely it is for adverse events to happen at different drug doses. 🌸By using this method, we can spot which doses carry higher risks 🌸Regression analysis uses math to show and predict how adverse effects changes as the drug dose increases.
POST-MARKETING SURVEILLANCE
DISPROPORTIONATE ANALYSIS A+OD 100 NO Disproportionality signal ✅ ✅ Observed = 100 ✅ Expected = 100 ✅ Observed = Expected ✅ NO DIFFERENCE! Disproportionality signal Detected ❌ A+OD 250 ❌ Observed = 250 ❌ Expected = 100 ❌ Observed Expected ❌ BIG DIFFERENCE!
BAYESIAN METHOD Allow us to update our knowledge about a drug as new data comes in! 📜 Starting point 📜Represents everything about the drug’s safety before analysing new reports 🔍 This is the new, objective evidence often from a clinical trial or from spontaneous adverse event reporting system that challenges the prior belief This is the result. 📜+🔍= ✅ ✅The Bayesian analysis mathematically combines the Prior belief with the new data to get the most accurate and updated assessment of risk
SIGNIFICANCE OF STATISTICAL METHODS IN EVALUATING MEDICATION SAFETY DATA Safety signal Detection Risk Quantification and Comparison Controlling for confounding factors Establishing Statistical significance Characterizing event timing Regulatory compliance Analysing rare events I MPOR T ANT
CONCLUSION 🤝Statistics are the indispensable bridge between data and decision 🤝They ensure early detection of unknown risks 🤝They validate risk assessments 🤝Never guessing, always quantifying! 🤝Focus on the patient 🤝Silent guardians of the public health
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