diff --git a/cumulus_library_covid/covid_symptom/table_prevalence_ed.sql b/cumulus_library_covid/covid_symptom/table_prevalence_ed.sql
index fa72d2a..9212f3a 100644
--- a/cumulus_library_covid/covid_symptom/table_prevalence_ed.sql
+++ b/cumulus_library_covid/covid_symptom/table_prevalence_ed.sql
@@ -28,12 +28,11 @@ join_2020 AS (
         p.subject_ref,
         p.encounter_ref,
         COALESCE(pcr.covid_pcr_result_display, 'None') AS covid_pcr_result,
-        CASE
-            WHEN dx.cond_code IS NOT NULL THEN True ELSE False
-        END AS covid_icd10,
+        COALESCE(dx.cond_code, 'None') AS covid_icd10,
         CASE
             WHEN
-                (dx.cond_code IS NOT NULL OR pcr.covid_pcr_result_display = 'POSITIVE') THEN True ELSE False
+                (dx.cond_code IS NOT NULL OR pcr.covid_pcr_result_display = 'POSITIVE')
+                THEN True ELSE False
         END AS covid_dx,
         COALESCE(nlp.symptom_display, 'None') AS covid_symptom,
         COALESCE(icd10.icd10_display, 'None') AS symptom_icd10_display