diff --git a/tests/testthat/test-relative-dates.R b/tests/testthat/test-relative-dates.R
index 4e46099..cb844ed 100644
--- a/tests/testthat/test-relative-dates.R
+++ b/tests/testthat/test-relative-dates.R
@@ -1,7 +1,7 @@
 test_that("Using relative and absolute dates gives the same answer", {
   # these take a while, so don't run on CI
   skip_on_ci()
-  dat_absolute <- data.table::fread(test_path("testdata", "delta_full_relative.rds"))
+  dat_absolute <- data.table::fread(system.file("delta_full.rds", package = "epikinetics"))
   mod_absolute <- biokinetics$new(data = dat_absolute, covariate_formula = ~0 + infection_history)
   delta_absolute <- mod_absolute$fit(parallel_chains = 4,
                    iter_warmup = 50,
@@ -11,7 +11,7 @@ test_that("Using relative and absolute dates gives the same answer", {
   set.seed(1)
   trajectories_absolute <- mod_absolute$simulate_individual_trajectories()
 
-  dat_relative <- data.table::fread(system.file("delta_full_relative.rds", package = "epikinetics"))
+  dat_relative <- data.table::fread(test_path("testdata", "delta_full_relative.rds"))
   mod_relative <- biokinetics$new(data = dat_relative, covariate_formula = ~0 + infection_history)
   delta_relative <- mod_relative$fit(parallel_chains = 4,
                    iter_warmup = 50,
diff --git a/vignettes/data.Rmd b/vignettes/data.Rmd
index d9aeac3..30f0dd8 100644
--- a/vignettes/data.Rmd
+++ b/vignettes/data.Rmd
@@ -2,9 +2,9 @@
 title: "A guide to model input and output data"
 output: rmarkdown::html_vignette
 vignette: >
-%\VignetteIndexEntry{A guide to model input and output data}
-%\VignetteEngine{knitr::rmarkdown}
-%\VignetteEncoding{UTF-8}
+    %\VignetteIndexEntry{A guide to model input and output data}
+    %\VignetteEngine{knitr::rmarkdown}
+    %\VignetteEncoding{UTF-8}
 ---
 
 ```{r, include = FALSE}