Introduction to Research and Clinical Epidemiology
The object of epidemiologic research
Is the occurrence of disease and it's relation to determinatnts
Good studies consist of...
Large sample size Good control of... Bias, confounding effects, random chance
The peer Review Process
Manuscript submitted Referred by editor to 2 or 3 reviews (non-biased) Authors respond to reviser questions and requests for clarifications Decision made ( Reject, Accept, accept if revised)
peer reviewed
Must pay to subscribe and articles are published only after careful analysis by experts
Non-peer reviewed
Often sent free to practitioners and report expert opinions rather than new data
What should a practitioner read?
One of the Big 4 At least one peer reviewed specialty journal. Throw-aways are
Two types of journals
Online and Pay-to-publish -legitimate but predatory
Why do ineffective treatments persist after published articles
Patient may recover in spite of treatment 3 popular rationalization -Didnt start right treatment soon enough -Didnt use the treatment long enough -Used inadequate dose of the treatment
Blinding controls for what
Patient: control placebo effect Researcher: Control for observer bias
Observer bias
People hear and see what they expect Patients want to please their doctors
The means by which new medical knowledge is gained
Research
The gold standard in Clinical Research
Double-blind, placebo-controlled trial
Which research is the best source for information
Evidence-based medicine
Why is human research difficult
Hard to control all the variables Hard to control bias and confounding Hard to control for random chance Hard to protect the rights and safety of patients
All placebos are not equal
Incision> injection> pill> touch> verbal Red pills are the best placebo Placebos can be influenced by culture
Results are published in
Medical literature
Question bias is a type of observation bias, what shouldn't your questions look like
Shouldn't ask" you are feeling better today, aren't you?
Epidemiology
The study of factors affection health and Illness of populations.
Effectiveness of placebos
They work best for subjective complains such as pain, well being, and mood They are effective for a brief period of time Work for less than 6 months