Table 2.

Total volume of EHR data related to clinician action for patients in the sepsis cohort within the first 24 hours after ED triage. Total items represent each instance of any EHR item while unique items represent the different types of items (eg, hospital admission order set, serum potassium, glycopeptide antibiotic). The table shows the total number of items and unique items initially extracted from the EHR (left), those removed for appearing only a single time (middle italics), and those ultimately included (right) in the count matrix for LDA implementation. Of the 3 478 677 total orders drawn from the EHR, 2 305 061 were part of an established order set and were included together with other orders that were part of the same order set and had the same time stamp as 1 instance of that order set, resulting in 248 120 total order sets.

	Items initially extracted from EHR		Items removed (appearing only once)	Items included in LDA count matrix
EHR item type	Total	Unique	Unique	Total	Unique
Orders
Individual	1 173 616	1657	236	1 173 380	1421
Order sets	248 120	238	24	248 096	214
Medications given	452 193	699	89	452 104	610
Procedures	17 806	464	188	17 618	276
Total	1 891 735	3058	537	1 891 198	2521

Abbreviations: EHR, electronic health record; LDA, Latent Dirichlet Allocation.