diff --git a/scripts/write-output/final-output-concepts.R b/scripts/write-output/final-output-concepts.R
index 075ba4f..9af8e24 100644
--- a/scripts/write-output/final-output-concepts.R
+++ b/scripts/write-output/final-output-concepts.R
@@ -37,6 +37,15 @@ combined_output_concepts <- bind_rows(combined_device,
                                       combined_healthkit)
 combined_output_concepts <- combined_output_concepts[!duplicated(combined_output_concepts), ]
 
+valid_participants <- 
+  read.csv(file.path(outputConceptsDir, "participant_devices.csv")) %>% 
+  distinct(participantidentifier) %>% 
+  pull()
+
+combined_output_concepts <- 
+  combined_output_concepts %>% 
+  filter(participantidentifier %in% valid_participants)
+
 combined_output_concepts %>% 
   write.csv(file.path(outputConceptsDir, "output_concepts.csv"), row.names = F)
 cat(glue::glue("output_concepts written to {file.path(outputConceptsDir, 'output_concepts.csv')}"),"\n")