Intent-to-Treat

Please provide a definition of the per protocol population and the intention to treat population Per protocol population Intention to treat population... 

The first-line regimen should contain a PPI plus clarithromycin and either amoxicillin or metronidazole. The combination of two antimicrobials and a PPI leads to cure rates greater than 80% (by intention-to-treat basis) and reduces the... 

Which patients should be in which data set is something that should be considered before analysis data sets are created. For example, it is often decided that all analysis data sets should have a record for a subject if that subject was randomized to treatment and is considered an intent-to-treat subject. Whether this is true or not, the specifications for analysis data sets should make it clear who should be present in any analysis data set. Here is a list of common populations and their definitions ... 

Intent-to-treat All patients randomized to a study therapy. It is intended that they will be treated. Patients are analyzed according to randomized treatment group. 

Another study with citalopram evaluated its efficacy in the treatment of social anxiety disorder along with co-morbid major depression (Schneier etal., 2003). The outpatients (n= 21) were predominantly Hispanic (76%) and from New York. Response rates for the intent-to-treat sample were 66.7% for social anxiety disorder and 76.2% for major depression. Only one subject was known to have withdrawn secondary to severe side effects. The mean dose of the medication was 37.6 mg/day and there was no placebo control. The depressive symptoms tended to improve... 

The results from an open-label, pilot study evaluating the efficacy of fluvoxamine for hypochondriasis were recently published (Fallon et al, 2003). The study sample included six Hispanics (subgroup unknown). Significant improvement (57.1%) was noted for the intent-to-treat group (eight out of fourteen) based on physicianrated and self-rated scales. The sample size was too small to identify differences in response or adverse effects by ethnicity. 

In accord with the fact that XPS has become a standard surface science technique but has not been appreciated adequately in electrochemistry, it is the scope of this review chapter to bring XPS nearer to those who work on electrochemical problems and convince electrochemists to use XPS as a complementary technique. It is not the intention to treat fundamental physical and experimental aspects of photoelectron spectroscopies in detail. There are several review articles in the literature treating the basics and new developments in an extensive and competent way [9,13], In this article basic aspects are only addressed in so far as they are necessary to understand and... 

Only RCTs should be analysed on the basis of intention to treat. ... 

In explanatory trials, we are hkely to exclude both protocol violators and treatment non-compliers. The objective behind these exclusions is to increase the efficiency. However the exclusions may give rise to bias and hence to compromise the results if too many patients are excluded. Such an analysis population is termed as completers, or per protocol, population. In pragmatic trials, we generally include all patients using the intention-to-treat (ITT) principle. 

The CARE-HF study was a European study of medical therapy alone versus medical therapy with the addition of a CRT pacemaker [119]. A total of 813 patients were enrolled and randomized in a 1 1 ratio prior to device implant, again a true intent-to-treat design. Patients were followed longer than in the COMPANION trial, for a mean of 29.4 months. The primary end point was the time to... 

If there are separate analysis plans for the clinical and economic evaluations, efforts should be made to make them as consistent as possible (e.g., shared use of an intention-to-treat analysis, shared use of statistical tests for variables used commonly by both analyses, etc.). At the same time, the outcomes of the clinical and economic studies can differ (e.g., the primary outcome of the clinical evaluation might focus on event-free survival, while the primary outcome of the economic evaluation might focus on quality-adjusted survival). Thus, the two plans need not be identical. 

Option 3 this is the only valid option. It is the only option that compares groups which are alike in terms of the mix of patients. This is the intention-to-treat option which compares the groups as randomised. 

The principle of intention-to-treat (ITT) tells us to compare the patients according to the treatments to which they were randomised. Randomisation gives us comparable groups, removing patients at the analysis stage destroys the randomisation and introduces bias. Randomisation also underpins the validity of the statistical comparisons. If we depart from the randomisation scheme then the statistical properties of our tests are compromised. 

The previous section clearly indicates the need to conform to the principle of intention-to-treat to ensure that the statistical comparison of the treatment groups remains valid. In practice compliance with this principle is a little more difficult and the regulators, recognising these difficulties, allow a compromise. This involves the definition in particular trials of the full analysis set which gets us as close as we possibly can get to the intention-to-treat ideal. 

The intention-to-treat principle implies that the primary analysis should include all randomised subjects. Compliance with this principle would necessitate complete follow-up of all randomised subjects for study outcomes. In practice this ideal may be difficult to achieve, for reasons to be described. In this document the term full analysis set is used to describe the analysis set which is as complete as possible and as close as possible to the intention-to-treat ideal of including all randomised subjects. ... 

The term full analysis set was introduced in order to separate the practice of intention-to-treat from the principle, but practitioners still frequently use the term intention-to-treat population when referring to this set. The term modified intention-to-treat population is also in common use within particular companies and also by regulators in some settings where exclusions from strict intention-to-treat are considered. 

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