QuestionSBA
QuestionChoice
The diamond shows the pooled result of all the studies. The vertical line indicates the line of no effect, i.e. the point at which there is statistically no significant difference between the control and intervention group. The width of the diamond illustrates the length of the confidence interval. Therefore, if the diamond touches the vertical line, it means that the overall result is **not** statistically significant
32053
a
If the diamond touches the solid vertical line, it indicates that the overall outcome is not statistically significant
QuestionChoice
The horizontal lines through the boxes illustrate the length of the confidence interval. A shorter line means that the confidence interval is very narrow, hence implying that the study is more reliable as there is a more precise estimate of effects. This is more likely to happen in larger studies with greater numbers of participants
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b
A shorter horizontal line suggests that the study is less reliable
QuestionChoice
A larger box would indicate a greater weight of that particular study in the pooled result. The horizontal lines through the boxes illustrate the length of the confidence interval; the longer the line, the wider the interval
32055
c
A larger box indicates a wider confidence interval for the study
QuestionChoice
Each box represents an individual study with the 95% confidence interval plotted as a horizontal line
32056
d
Each box with a horizontal line represents the results of a collection of studies
QuestionChoice
The interpretation would depend on whether the outcome of interest is desirable (e.g. cure) or adverse (e.g. death). If the outcome is desirable, results to the right of the vertical line will favour the treatment over the control
32057
e
If the results are to the right of the vertical line, it would always indicate that they favour the treatment over the control group
QuestionComment
it's a square...
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Monoclonal Lumbar
Concept
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# Definition 

A type of clinical study in which participants are assigned to groups that receive one or more intervention/treatment (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

# Types of interventional trials 

A randomized control trial is the strongest type of interventional trial, but other forms include non-randomised controlled trials, pre-post studies and quasi experiments.

A pre-post study is a study in which occurrence of an outcome is measured both before and after an intervention is administered; it is in this way that the effect of the intervention can be properly assessed. If the occurrence of the outcome was only measured after the intervention; the exact effect of the intervention cannot be determined.

Another form of trial is a crossover randomized control trial. A crossover RCT is a type of interventional study design where study participants intentionally “crossover” to the other treatment arm.

# Uses 

Interventional studies are used to answer study questions relating to either therapeutic agents, and evaluating the efficacy of therapeutic agents, or are used to assess mechanisms of preventing potential causes of damage.
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Interventional studies
Topic
51
Medical Statistics
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In forest plots, if the diamond intersects the vertical line, the overall result is statistically non-significant.
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Forest Plot.png
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Topic
51
Medical Statistics
Forest plots are often used to summarise the results of meta-analyses in a graphical form. An example is shown below:

[lightgallery]

Which of the following statements is true of a forest plot?
a