diff --git a/npRCT_functions.R b/npRCT_functions.R
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+# --------------------------------------------
+# --------------npRCT Function----------------
+# --------------------------------------------
+
+
+
+npRCT.pwr.t.test <- function(d1 = 0.5, d2 = 0.5, 
+                            sig.level1 = 0.05, sig.level2 = 0.05,
+                            power1 = 0.8, power2 = 0.8, 
+                            type1 = "two.sample", type2 = "two.sample", 
+                            alternative1 = "two.sided", alternative2 = "two.sided",
+                            suppressInfo = FALSE)    {
+    
+    # Load required package
+    require("pwr")
+    
+    # Run power calculation for first t-test (traditional part of RCST)
+    t1 <- pwr.t.test(d = d1, sig.level = sig.level1, power = power1, type = type1, 
+                     alternative = alternative1)
+    
+    # Run power calculation for second t-test (stratified part of RCST)
+    t2 <- pwr.t.test(d = d2, sig.level = sig.level2, power = power2, type = type2, 
+                     alternative = alternative2)
+    
+    # Compute sample sizes (per group)
+    n1 = ceiling(t1$n)
+    n2 = t2$n
+    n2_rct = ceiling(n2 / 2) # n still traditionally randomised in stratified part
+    
+    n_strat = n1 - n2_rct
+    n_total = n_strat + n2
+    
+    # Create output
+    output = data.frame(n_strat = n_strat,
+                        n_total = n_total)
+    
+    # Information message for output
+    if(suppressInfo == FALSE) {
+        cat("Find here sample sizes per group for the time point\nof stratification (=n_strat) as well as for the complete\nRandomised Controlled Stratified Trial (=n_total)\n\n")
+    }
+    
+    # End function by returning the output data.frame
+    return(output)
+}