diff --git a/workflow/apps/r/calculate_interaction_zscores5.R b/workflow/apps/r/calculate_interaction_zscores5.R
index 7a377dc1..1fc547ec 100644
--- a/workflow/apps/r/calculate_interaction_zscores5.R
+++ b/workflow/apps/r/calculate_interaction_zscores5.R
@@ -124,6 +124,7 @@ load_and_process_data <- function(easy_results_file, sd = 3) {
       delta_bg_tolerance = mean(delta_bg, na.rm = TRUE) + (sd * sd(delta_bg, na.rm = TRUE)),
       NG = if_else(L == 0 & !is.na(L), 1, 0),
       DB = if_else(delta_bg >= delta_bg_tolerance, 1, 0),
+      SM = 0,
       OrfRep = if_else(ORF == "YDL227C", "YDL227C", OrfRep),
       conc_num = as.numeric(gsub("[^0-9\\.]", "", Conc)),
       conc_num_factor = as.numeric(as.factor(conc_num)) - 1)