Questions tagged [prevalence]
The prevalence tag has no usage guidance.
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Relationship between sensitiviy, probability of detection and Prevalence
Folks, I have 3 questions:
If I know the number of exams performed with a specific test on a group of patients and the test's sensitivity, can I directly estimate the overall probability of detecting ...
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What data are used to find the final threshold for a medical diagnostic test?
Suppose I have some blood measurement X whose values correlate with some disease Y (so people with the disease use to have larger values of X). Moreover suppose that the disease is rare, say 1% of a ...
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Sample size calculation for prevalence studies: how do I find d when reviewing a published study?
I have found the following formula in Munn et al.:
$$N = \frac{Z^2 P(1-P)}{d^2}$$
$N$ = sample size
$Z$ = statistic for a level of confidence
$P$ = expected prevalence
$d$ = precision
The problem I ...
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Accounting for recall period in proportion meta-analysis
We are conducting a meta-analysis of "prevalence" of event-type exposures, e.g. "have you been physically assaulted in the past X months". We are trying to adjust for different ...
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What will be the sample size to determine the incidence and prevalence when estimated prevalence is 17.93 per 100000?
I want to conduct a study to determine the incidence and prevalence of oral cancer in an area. I prefer door to door community based screening by Oral visual examination and refer suspected case for ...
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R survey package: compare weighted prevalence with literature result
I have a large dataset (>3000 cases) with results of serological tests. Based on these results i want to calculate the weighted prevalence of the disease. The data is categorical (0 = disease ...
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37
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Prevalence / Incidence and Relative Risk
I'm doing a course in biostatistics and I came across this question to solve:
"Consider a two-year follow-up study of the association between a measure
of stress (dichotomised into two levels: ...
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Appropriate statistical test evaluating difference in proportions between two groups over multiple time points
Over the course of a year, I took samples from dogs and their beds and looked for the type of bacteria in the bed and in the dog every month. I did not get samples from the same dogs or the same beds ...
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How should the prevalence be calculated when determining prevalence-adjusted PPV?
I am assessing the performance of a test for a certain disease. I have selected the disease cases and controls from a large dataset that is reasonably representative of the general population.
As I ...
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How to relate prevalence to factors with multivariate analyses model (GAM beta inflated)?
While analizing the prevalence of cows to brucellosis (illness), and in order to relate it to a set of factors like country, state, and detection technique, I need to apply a multivariate analysis ...
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Adjust a crude rate based on observed prevalence within population [closed]
I have data such as the below:
Area
Admissions
Population
Crude rate per 100,000
Cambridge
137,204
1,077,382
12,735
London
111,896
1,013,985
11,035
I have been asked to 'adjust the crude rate for ...
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Age Adjusted Prevalence at region level with only country-level population distribution
I'm trying to calculate age-adjusted prevalence for a bunch of different chronic diseases from hospital data in a specific area and I'm having some difficulty. I have total country level population, ...
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Accounting for overrepresentation of positives in binary classification test set for calculation of precision and recall
I have a binary classification task with highly imbalanced data, since the class to be detected (in the following referred to as the positives) is very rare.
For data limitation reasons my test set ...
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Calculating the confidence interval or standard error of a PPV adjusted for prevalence
I am trying to evaluate how well a disease test performs in a case-control study. In this example, the prevalence is 0.5%, and the results are below:
Disease +
Disease -
Test +
40 (TP)
10 (FP)
Test ...
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What is the probability of at least one person in a sample of k people being infected?
Given the prevalence, sensitivity and specificity of a single test are known.
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