PHIN MESSAGING GUIDE FOR SYNDROMIC SURVEILLANCE: QUESTIONS & ANSWERS

PHIN SS Guide Q and A (final).docx Page 1 

Question # 1: 

What is the relationship between the “Final Recommendation: The Core Processes & EHR Requirements of Public 

Health Syndromic Surveillance” (PHSS)1 document released by the International Society for Disease Surveillance 

(ISDS) and the PHIN Messaging Guide for Syndromic Surveillance? 

Answer: 

The ISDS document1

, in Section 1.1, states that its purpose is “...to define the core of PHSS practice and the EHR data 

requirements widely needed to support the core.” CDC’s PHIN Messaging Guide for Syndromic Surveillance 

provides technical specifications and implementation guidance to support the exchange of the core syndromic 

surveillance data from healthcare to public health in accordance with the ISDS document. 

Question # 2: 

How will the PHIN Messaging Guide for Syndromic Surveillance be maintained and updated in the future? 

Answer: 

The CDC will issue new versions of this guide as necessary to incorporate additions and modifications to the 

syndromic surveillance business standards and data requirements. The CDC will collaborate with ISDS to address 

and incorporate modifications based on but not limited to ISDS input; public comments; feedback from CDC, state 

and local public health agencies and vendors; and input from public health partner organizations in the development 

of future versions of this guide. 

Note: Refer to Section 2.5 for a more details 

Question # 3: 

What data source(s) does the PHIN Messaging Guide for Syndromic Surveillance support? 

Answer: 

Within the ISDS document1, Section 1.2.1 defines the most important data sources for syndromic surveillance: 

emergency department (ED) and urgent care (UC) patient visits captured by health information system and sent to a 

public health authority. These data sources are in scope of the ISDS Recommendations1 and provide the foundation 

for the PHIN Messaging Guide for Syndromic Surveillance. In the future, ISDS will extend the scope of data sources 

for syndromic surveillance and updated versions of the PHIN Messaging Guide for Syndromic Surveillance will be 

published. 

Question # 4: 

The PHIN Messaging Guide for Syndromic Surveillance indicates (see Section #6) the PHIN Message Quality 

Framework (MQF) will support real time validation of syndromic surveillance messages. How will MQF support the 

validation of these messages? 

Answer: 

Implementers will be able to use MQF to validate messages they create during their development and testing 

phases. The MQF tool will perform several validations on syndromic surveillance messages based on the technical 

specification contained in the PHIN Messaging Guide for Syndromic Surveillance. 

Question # 5: 

If a sender does not have a value for a data element with a usage type of “RE” and the data element is sent in an 

OBX segment, is it necessary to include an OBX segment for that data element with an empty OBX-5 field? 

Answer: 

No. Since the usage is “RE” and the sender does not have a value for the data element it is not necessary to include 

an OBX segment for that data element. 

 

1

International Society for Disease Surveillance, Final Recommendation: The Core Processes and EHR Requirements of Public Health Syndromic Surveillance.

International Society for Disease Surveillance, Brighton, MA (January 2011); http://www.syndromic.org/projects/meaningful-use
PHIN MESSAGING GUIDE FOR SYNDROMIC SURVEILLANCE: QUESTIONS & ANSWERS

PHIN SS Guide Q and A (final).docx Page 2 

Question # 6: 

Can a single batch contain different types of syndromic surveillance messages? 

Answer: 

Yes. For example, a batch may contain Admin/Visit Notifications (ADT^A01) and Discharge/End Visit (ADT^A03) 

messages. 

Question # 7: 

Are receivers required to acknowledge all syndromic surveillance messages? 

Answer: 

The guide includes the specifications for the acknowledgement messages, but the sender and receiver will decide 

whether or not to use acknowledgement in their specific data exchange implementation. 

Question # 8: 

Why didn’t the CDC publish separate PHIN Messaging Guides for Syndromic Surveillance for each of the supported 

HL7 Versions (2.3.1 and 2.5.1)? 

Answer: 

Based on the currently recommended by ISDS core syndromic surveillance data elements, there are just two basic 

differences between the syndromic surveillance message for HL7 version 2.3.1 and 2.5.1 - HL7 2.3.1 doesn’t have the 

MSH-21 (Message Profile Identifier) and the ENV-7 (Event Facility) fields. Therefore, the guide identifies how to 

construct both HL7 2.3.1 and HL7 2.5.1 messages to accommodate these differences. 

(Note: See Section 2.4 for additional details.) 

Question # 9: 

Our state requires triage notes for a patient visit and the clinical impression of the diagnosis for syndromic 

surveillance. However the PHIN Messaging Guides for Syndromic Surveillance specifies the usage of the triage notes 

and clinical Impression data elements to be optional. Can we make these data elements required for our 

jurisdiction? 

Answer: 

Yes. As necessary, states may add data elements, modify the data element usage and/or constrain message 

elements to support their specific requirements, laws and regulations. 

Question # 10: 

Why are three syndromic surveillance data element tables provided in Section 4? 

Answer: 

The table in Section 4.2.1 contains the syndromic surveillance core data elements that ISDS identified as the 

minimum set commonly used by public health for syndromic surveillance. The other two tables, in Sections 4.2.2 

and 4.2.3, are provided to inform implementers of the other data elements identified by ISDS that may be used by 

jurisdictions to extend the core data set or that will be considered for inclusion into the core minimum data set in 

the future.