Karteikarten
Randomized Trial
Karten in diesem Stapel (44)
- 1Randomized are imporant inevaluating for the prevention, dignosis, and treatment of disease
- 2RT can asnwer:more than one question at a time( factorial and other desighns)
- 3RT in some situations:can randomize entire groups ) communites, medical practices)
- 4In order to assess causal effects we shouldcontrast the outcome of people exposed to a risk factor with what would have happend in the absence of exposure
- 5The theoretically ideal way to assess what would have happened in the absence of exposure is termed the___counterfactual
- 6What is an imossible study desighnCompare the oucomses f a person exposed to a risk factor with the same person not exposed to the risk factor, at the same time and in the same place
- 7The closest we can come to such desighn isexperimental study
- 8What is the Evidence of Treatment Efficacy Hierarchy: (6)1.Anecdotal Case Reports 2.Case series w/o controls 3.Cross-sectional studies 4.Case-Control studies
5.Longitudinal studies
6.Randomized clinical trials - 9An experimental study can determine: (2)If the factor prevents disease or if the therapeutic is an effect treatment
- 10What is the gold standardThe randomized trial is for assess the relationship between a therapeutic or clinical intervention and a disease outcome
- 11Another word for efficacy isinternal valididty
- 12One reason why we randomize:Self Selection to the treatment group is eliminated: studying the association between HTR and heart disease
- 13What is the second reason why we randomizePredictive factors (known and unknown) tend to be balances between intervention and comparison groups
- 14Predictive facotors:known factors have been assessed in the study, and unknown factors may affect the outcome. but have not been assess in the sudy
- 15THe observation studies of smoking cessation aids are fraught withselection biasis which typically deomstrates that the smoking cessation aids are ineffective( and selction bias)
- 16Explain the selection bias in smoking cessation studiesREaltionshps among use of cessation aids, nicotine dpendence and abistence are complicated: 3 self selcting groups
- 17In a RT the "current treatment can either__be given no treatment or the existing standard of care
- 18In RT the length of time between treatment and assessment will depend onwhat is being studied
- 19New treatment group=intervention group
- 20current treatment group=non intervention or control group
- 21In RT:There is defined population which will be randomized into a new treatment and current treatment and both into improved and not improved
- 22In an experiemtal study the advantage is that you canramdomize the intervention and no intervention group
- 23Rondomization is generally carried out usingcomupter generated random numbers
- 24For large studies, randomization should result in ____equal proportions of prognostic risk factor between the two groups, or also stratified randomization
- 25Validity of a randomized trial largely depends onsucess of the randomization process
- 26What is step one in stratifying randomizationStratify our study population by each variable that we consider important
- 27Step 2 in stratifying randomizationRandomize participants to treatment groups within each stratum
- 28In a double blinding Participants are__not aware of their intervention or treatment status
- 29In a double blinding Data collectors/analysts cannot___identify participants as being in the intervention or control groups
- 30In a DB: Study participantsdo not know which groups they are assighned to
- 31In a DB: Data collectors/ analystsdo not know which groups the patients have been assigned to when outcomes
- 32In a planed Cross over dseighn individualsswitch treatment and act as their own controls
- 33PCD is not possible iftherapy is surgical or cures the disease
- 34What are some precautions in a PCD:Carryover effects of one therapy into second therapy : may need a washout period
- 35a factorial randomized design is:A randomized trial design for evaluating 2 drugs or therapeutics "simultaneously" in the same study population
- 36a FRD can only be used ifthe anticipated outcomes of 2 drugs are "independent" and thier modes of action are "independent"
- 37Factorial Desighn example to assess preventive effects of1. Beta-Carotene on Cancer 2. Aspirin on myocardial infarction
- 38What is external valididtydetermined by how closely matched the study population is to the reference (or general) population
- 39Internal validity is determined byrandomization process, and is achieved when an observed difference (or lack of difference) in the treatment and control groups can be attributed to the treatment alone
- 40Externa validiy ( Generalizabilty) deals withRefernce population to the study population
- 41Internal validity deals withnew treatment and current treatment after they were randmized from te study population
- 42What are some units of group randomizationscommunities, small town, factories, schools, religious insitutions, chapters of social organizations, clinical practices
- 43Randomizing Groupsare less efficient statistically than randomization by individual
- 44In Randomized Groups the design and analysis must account forthe correlation of individuals within a group
Informationen
- Beschreibung
- college Epid (Cross Sectional Study) Karteikarten am Randomized Trial, erstellt von maxytrejo1 am 22/05/2014.
- Erstellt von
- maxytrejo1
- Aufrufe
- 23
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