PPT-Selection Bias for Compounds with Positive Phase 2 Results

Simon Kirby David Li and Christy ChuangStein PSI Conference 2017 Grange Tower Bridge Hotel London Pfizer ChuangStein Consulting Layout The problem Some examples Some possible bias adjustment methods. Selection Bias Selection bias is a distortion in a measure of association rate ratio risk ratio or odds ratio Selection bias usually occurs as a result of either using improper procedures for obtaining persons from the target population to become me When the patient recruitment decision is influenced by the knowledge of upcoming treatment allocation selection bias is inevitable and the validity of the trial result is seriously damaged Allocation concealment is defined as the procedure for prote Why is it so damn confusing?. Marc V. Gosselin. Disease or Outcome. +. -. +. -. Exposure. a. b. c. d. n. Basic Measures. Incidence. Estimate of risk. Need a cohort study (follow-up). Cumulative. Number of new cases in a period of time/total population at risk. Selection bias Information bias Confounding bias Bias is an error in an epidemiologic study that results in an incorrect estimation of the association between exposure and outcome. Is present when th Step 3: Critical . appraisal of studies. 5-step approach. EBMgt is a 5-step approach. Formulate an answerable question (PICOC). Search for the best available evidence. . Critically . appraise the quality of the found evidence. Mgr. Pavel Reich. 1. Outline. Hidden bias as a form of doublespeak. Presidential Debates. Example of the use of hidden bias. Results of the analysis. 2. Doublespeak. Doublespeak - language that pretends to communicate but really doesn’t. It is language that makes the bad seem good, the negative appear positive, the unpleasant appear attractive or at least tolerable. Doublespeak is language that avoids or shifts responsibility, language that is at variance with its real or purported meaning. It is language which conceals or prevents thought; rather than extending thought, doublespeak limits it (Lutz 1990:1). HSB4M Culminating Activity . Oh Yea, and How To Do It Right!. No, we would NEVER do that…... Instead of taking all the bother and time to sample at all…... Biased Sampling. There are many different types of sampling bias. Some . Hua . zhang. 1. Questions. :. Do people’s beliefs in different outcomes change as a result of searching?. Do search engine results bias in favor of particular outcomes?. What is the impact of bias on search outcomes, specifically on answer accuracy?. David . Perry. a,b. , Kim . KcKelvey. b. , Sophie . Kinnear. b. , Dmitry . Momotenko. b. , Joshua . Byers. b. and Patrick . Unwin. b. a) MOAC DTC b) Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, Warwickshire. Hua . zhang. 1. Questions. :. Do people’s beliefs in different outcomes change as a result of searching?. Do search engine results bias in favor of particular outcomes?. What is the impact of bias on search outcomes, specifically on answer accuracy?. Validity and testing for validity. Reliability and testing for reliability. Group task for today. Bias is a . systematic . error in the design, conduct, or analysis of a study that results in errors when calculating measures of association between risk factors and outcomes. Critical. . appraisal of medical literature . 2010. 9. 고려대학교 의과대학. 안 형 식. What is bias?. Systematic error or deviation from the truth. may overestimate or underestimate. biased studies lead to misleading results. . . What do we mean by confidence in a systematic review and in an estimate of effect?. How should we assess how much confidence to place in a systematic review of health systems research?. What do we mean by confidence in a systematic review?. Library service, University Hospitals Bristol. Critical Appraisal. What is Critical Appraisal?. Critical appraisal is an assessment of the strengths and weaknesses of research methodology. It aims to examine .