vitaminL

Data from the vitamin Study,
a randomized study where the growth of guinea pigs was monitored before and after intake of vitamin E/placebo.
The weight of each guinea pig was recorded at the end of week 1, 3, 4, 5, 6, and 7. Vitamin E/placebo is given at the beginning of week 5.
This dataset is in the long format (i.e. one line per measurement).
<ul>
<li><code>group</code>: treatment group: vitamin or placebo.</li>
<li><code>animal</code>: identifier</li>
<li><code>weight1</code>: weight (in g) of the pig at the end of week 1 (before treatment).</li>
<li><code>weight3</code>: weight (in g) of the pig at the end of week 3 (before treatment).</li>
<li><code>weight4</code>: weight (in g) of the pig at the end of week 4 (before treatment).</li>
<li><code>weight5</code>: weight (in g) of the pig at the end of week 5 (after treatment).</li>
<li><code>weight6</code>: weight (in g) of the pig at the end of week 6 (after treatment).</li>
<li><code>weight7</code>: weight (in g) of the pig at the end of week 7 (after treatment).</li>
</ul>

datasets

Companion R package for the course "Statistical analysis of correlated and repeated measurements for health science researchers"
taught by the section of Biostatistics of the University of Copenhagen.
It implements linear mixed models where the model for the variance-covariance of the residuals is specified via patterns (compound symmetry, toeplitz, unstructured, ...).
Statistical inference for mean, variance, and correlation parameters is performed based on the observed information and a Satterthwaite approximation of the degrees of freedom.
Normalized residuals are provided to assess model misspecification.
Statistical inference can be performed for arbitrary linear or non-linear combination(s) of model coefficients.
Predictions can be computed conditional to covariates only or also to outcome values.

vitaminL: Data From The Vitamin Study (Long Format)

Description

Usage

Arguments

References