Publications by Pedro Henrique Brant
tinv - a function in R to emulate the one in Microsoft Excel
While working on the sample size calculation for the PPCR group project, I encountered a problem: one of the papers we were trying to use (D’Silva et al., 2023) did not report the standard deviation (SD) for the primary outcome. Then, when we were trying to calculate the standardized mean difference, we had some trouble. Professor David Wypi...
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Sample Size with David
Sample Size with David Calculating the Sample Size with Z-value Consider power = 0.9 Using this website to get the z-score (can this be the source of error? How to get the z-score in another manner?) Z-score = 1.17 (p-value 0.242) Z-score = 1.09 (p-value 0.277) sd = 7.5842 (for z = 1.17, n = 38) sd = 3.2381 (for z = 1.09, n = 41) effect size = 3...
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Association between sleep quality and pain in older adults
Introduction In this manuscript, we’re going to conduct an analysis into the ELSI Dataset. This is a modified version for usage in the Principles and Practice of Clinical Research program of Harvard T.H. Chan School of Public Health. The aim here is to replicate the analysis done in a previous paper and see if the results also apply to the sa...
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What is the association between sleep quality and pain (presence and intensity) in older adults?
In this manuscript, we’re going to conduct an analysis into the ELSI Dataset. This is a modified version for usage in the Principles and Practice of Clinical Research program of Harvard T.H. Chan School of Public Health. The aim here is to replicate the analysis done in a previous paper and see if the results also apply to the sample that was...
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Testing assumptions
Daniel has modified the original dataset and has added the variables “sleep_sum”, “pain_sum” and “covariates_sum”. I’ll undertake some exploratory data analysis. First order of business is to read in the data: require(tidyverse) ## Loading required package: tidyverse ## ── Attaching packages ────────────�...
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Multivariable model for association between sleep quality and pain in older adults
Previously, in another Rpubs post I discussed building regression models in order to test for the relationship between sleep quality and pain in the ELSI dataset. Now, we’re going to build a model which adjusts for covariates when examining this relationship. Let’s read the data (we’re using a modified version of the dataset provided by ...
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Analysis of dichotomous variables
In the last Rpubs post we tried to establish a model, using a modified version of ELSI dataset, to show association between pain intensity and sleep quality. Unfortunately, probably due to the large amount of missing observations in the pain intensity variable, the model was invalid, as the assumptions weren’t met. In this new analysis, we w...
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Effect of Baseline Variables in the Effect of Asthma Treatments in Children
In my last published analysis I tried to ascertain if the baseline value of hemoglobin affected treatment effectiveness in the CAMP teaching dataset. In this new analysis, we’re going to try to create a model that takes into account all the measured baseline characteristics to see if they can explain the differences that arise in treatment ...
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Does baseline hemoglobin change the effect of potential asthma treatments?
When answering the Lecture 11 assignment for PPCR, I was introduced to the CAMP dataset. In this dataset, the effect of two different treatments in asthmatic children was evaluated and compared to placebo. In the feedback I received for that assignment, Carla Mori, my TA, suggested the following: As a secondary analysis, If you would like to g...
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Assignment for Lecture 11 PPCR
This week’s assignment asks us to review the CAMP dataset, develop a question, run the analysis on the dataset and report our conclusions. The assignment asked us to do this in STATA, but, as I’ve enjoyed using R much more than STATA and find that publishing R markdown documents makes for a much clearer and reproducible report, I’ll be do...
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