diff --git a/.Rbuildignore b/.Rbuildignore
index 6008b579d5dd55cd0c61aa4e05404c8437d91f3f..4212858235c6fea27a834c5e1a0012856a4ec6c9 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -10,7 +10,7 @@ README\.md$
 vignettes
 .gitlab-ci.yml
 # unit tests should be ignored when building the package for CRAN
-^tests$
+#^tests$
 # CDO is not in windbuilder, so we can test the unit tests by winbuilder
 # but test-CDORemap.R and test-Load.R needs to be hidden
 #tests/testthat/test-CDORemap.R
diff --git a/R/Trend.R b/R/Trend.R
index 1f714a6fac3b87e9c2796afcbfde6d3d4cb42fc7..d709101a681eec1bab3104081bb184356d2fd0ba 100644
--- a/R/Trend.R
+++ b/R/Trend.R
@@ -50,7 +50,9 @@
 #'  \code{conf = TRUE}.
 #'}
 #'\item{$p.val}{
-#'  The p-value calculated by anova(). Only present if \code{pval = TRUE}.
+#'  A numeric array of p-value calculated by anova(). The first dimension 
+#'  'stats' is 1, followed by the same dimensions as parameter 'data' except 
+#'  the 'time_dim' dimension. Only present if \code{pval = TRUE}.
 #'}
 #'\item{$detrended}{
 #'  A numeric array with the same dimensions as paramter 'data', containing the 
@@ -188,7 +190,7 @@ Trend <- function(data, time_dim = 'ftime', interval = 1, polydeg = 1,
     }
 
     if (pval) {
-      p.val <- rep(NA, polydeg + 1)
+      p.val <- as.array(NA)
     }
 
   }
diff --git a/man/Trend.Rd b/man/Trend.Rd
index d283ee652d6795f127c6853e5dfa52e9715ce2e9..7623c3613149b891a5bf83c26bb32fb56716c541 100644
--- a/man/Trend.Rd
+++ b/man/Trend.Rd
@@ -66,7 +66,9 @@ A list containing:
  \code{conf = TRUE}.
 }
 \item{$p.val}{
- The p-value calculated by anova(). Only present if \code{pval = TRUE}.
+ A numeric array of p-value calculated by anova(). The first dimension 
+ 'stats' is 1, followed by the same dimensions as parameter 'data' except 
+ the 'time_dim' dimension. Only present if \code{pval = TRUE}.
 }
 \item{$detrended}{
  A numeric array with the same dimensions as paramter 'data', containing the 
diff --git a/tests/testthat/test-Trend.R b/tests/testthat/test-Trend.R
index 49a998229f5ca9336bb5a7c06c1eb8144922411e..07da6ce45c6b687c8e0ef9a7f746be1794d83b50 100644
--- a/tests/testthat/test-Trend.R
+++ b/tests/testthat/test-Trend.R
@@ -112,6 +112,22 @@ test_that("2. Output checks: dat1", {
     0.1153846,
     tolerance = 0.001
   )
+  expect_equal(
+    dim(Trend(dat1)$trend),
+    c(stats = 2, dat = 1, sdate = 2)
+  )
+  expect_equal(
+    dim(Trend(dat1)$p),
+    c(stats = 1, dat = 1, sdate = 2)
+  )
+  expect_equal(
+    dim(Trend(dat1)$detrend),
+    c(ftime = 13, dat = 1, sdate = 2)
+  )
+  expect_equal(
+    dim(Trend(dat1, polydeg = 3)$trend),
+    c(stats = 4, dat = 1, sdate = 2)
+  )
 
 })
 
@@ -176,8 +192,32 @@ test_that("5. Output checks: dat4", {
     as.numeric(rep(NA, 5))
   )
   expect_equal(
-    Trend(dat4)$p.val[, 1, 1, 1],
-    c(NA, 0.01800594),
-    tolerance = 0.0001
+   dim(Trend(dat4)$p.val),
+   c(stats = 1, lat = 2, lon = 3, lev = 2)
+  )
+  expect_equal(
+    is.na(Trend(dat4)$p.val[, 1, 1, 1]),
+    TRUE
   )
+  expect_equal(
+    as.vector(Trend(dat4)$trend[1, 2, , ]),
+    as.vector(Trend(dat3)$trend[1, 2, , ])
+  )
+  expect_equal(
+    as.vector(Trend(dat4)$p.val[1, 2, , ]),
+    as.vector(Trend(dat3)$p.val[1, 2, , ])
+  )
+  expect_equal(
+    as.vector(Trend(dat4)$conf.l[1, 2, , ]),
+    as.vector(Trend(dat3)$conf.l[1, 2, , ])
+  )
+  expect_equal(
+    as.vector(Trend(dat4)$conf.u[1, 2, , ]),
+    as.vector(Trend(dat3)$conf.u[1, 2, , ])
+  )
+  expect_equal(
+    as.vector(Trend(dat4)$de[1, 2, , ]),
+    as.vector(Trend(dat3)$de[1, 2, , ])
+  )
+
 })