Lecture on Epidemiology and Evidence-Based Medicine

Introduction to Epidemiology

• Epidemiology: Science of determining if something is beneficial or harmful in the real world.
• Often misunderstood; linked to sensationalized newspaper headlines.
• Examples: Daily Mail headlines dividing objects into cancer-causing or preventing categories.

The Role of Evidence in Science

• Science is about critically appraising evidence, not relying on authority.
• Importance of questioning scientific claims in academic settings.

The Weakness of Authority

• Authority in Science: Not based on titles or qualifications; requires evidence.
• Example: Dr. Gillian McKeith presented as an authority despite questionable credentials.
• Misleading claims about nutrition and health.

Proper Scientific Evidence

• Real Science Example: Misinterpretation of studies by media.
• Red wine and breast cancer study illustrates misunderstanding of lab results as direct health advice.

Observational Studies vs. Trials

• Observational Studies: Provide correlations but not causation.
  • Example: Olive oil and wrinkle study misinterpreted correlation.
• Trials: More reliable; ideally involve control groups to establish causation.
  • Biblical reference to Daniel 1:12 as an early trial.

Placebo Effect and Trials

• Importance of control groups to account for placebo effect in trials.
• Placebo Examples:
  • Two sugar pills more effective than one for gastric ulcers.
  • Saltwater injections more effective due to perceived intervention.

Pharmaceutical Industry Tactics

• Similar deceptive tactics as media but more sophisticated.
• Trials often compared against placebo, avoiding comparisons with existing treatments.

Manipulating Trial Results

• Rigging trials by:
  • Comparing new drugs with ineffectively dosed alternatives.
  • Example: Antipsychotic drugs trials with manipulated doses.

Missing Data in Trials

• Industry-funded trials more likely to show positive results due to unpublished negative data.
• Publication Bias: Funnel plots demonstrate missing negative trials.
• Reboxetine Example: Majority of trials withheld, misleading prescribers.

Current Ethical Problem in Medicine

• Withholding data from systematic reviews and meta-analyses.
• Example: Tamiflu data withheld, impacting decision-making on flu prevention.

Conclusion

• Highlighting the need for transparency in science.
• Encourages scrutiny and openness to improve scientific integrity.
• Emphasizes the importance of making all trial data available.