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Unformatted text preview: s is per protocol analysis This is ‘per protocol’ analysis Effectiveness Effectiveness study Does the intervention have an effect in the entire Does the intervention have an effect in the entire group group of people to whom it is assigned? This is intention This is ‘intention-to-treat’ analysis analysis Once Once randomized, always analyze! Run in periods to test compliance of study Run-in periods to test compliance of study participants participants with assigned treatment in study protocol
25 5. Report study outcome 5. Report study outcome
Ethical responsibility to report ALL results Ethical responsibility to report ALL results, positive and negative, for all outcomes studied (avoid negative publication bias) (avoid negative publication bias) Register Register study at onset with clinical trial registry registry Make Make results publically available /www.scielosp.org/scielo.php?pid=S0042/scielo.php?pid=S004296862008000600021&script=sci_arttext&tlng =en
26 Factorial Design Example Factorial Design Example Aspirin Group ß-carotene Placebo CHD deaths Placebo Group
ß-carotene Placebo Present
Physician’s Health Study Future 27 Assessing Assessing the Association of Aspirin and B-carotene on the Risk of and carotene on the Risk of Coronary Coronary Heart Disease (CHD)
CHD Aspirin YES YES NO NO YES B-carotene NO YES NO a A c C b B d D
28 Community Trial Example Community Trial Example
58 mandated community 11 intervention smoking cessation cities activities
Randomized Quit rate 11 control cities Usual activities Quit rate Baseline prevalence to establish cohort of smokers Present
29 Future Case Case-crossover Design Design Group 1 Aspirin Ibuprofen Assess pain Group 2
Ibuprofen Aspirin Assess pain Present Future 30 Within Within-Subject Cross over design Cross over design
Do food colors increase hyperactivity in young Do food colors increase hyperactivity in young children? children? 22 children with hyperactivity put on diet free 22 children with hyperactivity put on diet free of of food colors. Parents...
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- Spring '08