A very secretive example. A clinical trial was planned with the ﬁnal sample size of 250 per. treatment. There is going to be one interim analysis with possible termination. (efﬁcacy or futility) at N =150. The study was powered to detect a difference of 37:5. The (common) standard deviation was assumed to be 128.
http://www.mc.vanderbilt.edu/crc/workshop_files/2009-07-31.pdf
The First Received date is the date on which summary clinical study protocol information was first submitted to the ClinicalTrials.gov registry. There is typically a delay of a few days between the First Received date and when the study information is available on ClinicalTrials.gov.
https://clinicaltrials.gov/ct2/about-studies/glossary
The estimated primary completion date is the date that the researchers think will be the Primary Completion Date for the study. The Primary Completion Date is the term used on ClinicalTrials.gov for completion date as defined in Section 801 of the Food and Drug Administration Amendments Act of 2007.
https://clinicaltrials.gov/ct2/about-studies/glossary
TRIGGER was an open-label cluster randomised trial whose primary outcome was further bleeding. Because of the cluster randomisation, all researchers in a hospital were aware of treatment allocation and so could not perform a blinded assessment.
http://trialsjournal.biomedcentral.com/articles/10.1186/1745-6215-15-456
A type of clinical trial in which observations made during the trial are compared to a standard, called the control. The control may be observations of a group of participants in the same trial or observations from outside the trial (for example, from an earlier trial, which is called a historical control).
https://clinicaltrials.gov/ct2/about-studies/glossary
A planned measurement described in the protocol that is used to determine the effect of interventions on participants in a clinical trial. For Observational studies, a measurement or observation that is used to describe patterns of diseases or traits, or associations with exposures, risk factors, or treatment.
https://clinicaltrials.gov/ct2/about-studies/glossary
Data collected at the beginning of a clinical study for all participants and for each arm or comparison group. These data include demographics, such as age and gender, and study-specific measures (for example, systolic blood pressure, prior antidepressant treatment).
https://clinicaltrials.gov/ct2/about-studies/glossary
For objective outcomes, such as all-cause mortality, unblinded assessment is unlikely to bias the trial results [5]. However, evidence suggests that treatment effect estimates may be exaggerated for subjective outcomes when outcome assessors are not blinded [6–13].
http://trialsjournal.biomedcentral.com/articles/10.1186/1745-6215-15-456
Interim Analysis in Clinical Trials. Clinical Trial. - is a clinical investigation of a drug that is administered or dispensed to. human subjects. - is a prospective study comparing the effects and values of intervention(s) against a control in human subjects.
http://www.mc.vanderbilt.edu/crc/workshop_files/2009-07-31.pdf
Direct assessment by a blinded clinician. Blinded assessment may not be feasible in trials where all clinicians or researchers in a centre are aware of treatment assignment by necessity (for example, in a cluster randomised trial where all patients in a centre receive the same treatment).
http://trialsjournal.biomedcentral.com/articles/10.1186/1745-6215-15-456
when a trial is complete is data unblinded
No, when a trial is complete, data is not unblinded. No, when a trial is complete then the data is not unblinded.