NNDSS Case Notifications
CDC_NNDSSfree12 data-quality rules for National Notifiable Diseases Surveillance System (NNDSS) case notifications sent from states/jurisdictions to CDC, per the HL7 v2.5.1 Generic Message Mapping Guide (MMG) and PHIN Messaging Specification. Covers strictly-required ("R") data elements, PHIN VADS value sets (condition, case status, case class, sex, race, ethnicity, jurisdiction), date logic, timeliness, and duplicate suppression. HL7 messages missing required elements are rejected — clear these before transmission.
Checks included (20)
Case Status Is Valid(case_status)
MMG case status (Case Class Status) must be a coded value: confirmed, probable, suspect, or unknown (SNOMED-coded per PHIN VADS).
Administrative Sex Is Valid(patient_sex)
Patient administrative sex must be a value from the HL7/PHIN VADS sex value set (M, F, O, U, A, N).
Ethnicity Is Valid(patient_ethnicity)
Ethnicity must be a value from the CDC ethnicity group value set (Hispanic or Latino, Not Hispanic or Latino, Unknown).
Age Units Are Valid(age_units)
Patient age units must be a valid UCUM/PHIN age-unit code (years, months, weeks, days, hours, minutes).
Hospitalized Indicator Is Valid(hospitalized)
The hospitalized indicator must be a valid yes/no/unknown code.
Pregnancy Status Is Valid(pregnancy_status)
Pregnancy status, when reported, must be a valid yes/no/unknown/ not-applicable code.
Reporting Source Type Is Valid(reporting_source)
The reporting source type must be a valid PHIN code (laboratory, hospital, physician, clinic, other).
Condition Code Is a Notifiable Condition (PHIN VADS)
The reported condition code must exist in the PHIN VADS Nationally Notifiable Condition value set. Non-notifiable or retired condition codes cannot be processed.
Race Coded in the CDC Race Value Set
Race must be coded against the CDC Race & Ethnicity (PHIN VADS) value set so demographics aggregate consistently across jurisdictions.
Reporting Jurisdiction Is Valid
The reporting jurisdiction must be a valid state/territory FIPS code so the notification routes to the correct surveillance program.
Country of Residence Is Valid ISO 3166
The patient's country of usual residence must be a valid ISO 3166 country code.
Strictly-Required (R) Elements Present
The Generic MMG marks core elements as strictly required ("R"): condition code, case status, reporting jurisdiction, and report date. HL7 messages missing any are rejected at CDC.
Patient Age or Birth Date Present
Either patient age (at onset/diagnosis) or birth date must be present; age is essential for surveillance stratification.
Diagnosis / Onset Date Present
Each notification must carry a diagnosis or illness-onset date for time-series surveillance.
Onset Date Not After Report Date
Illness onset cannot occur after the date the case was reported. A reversed sequence indicates a date-entry error.
Confirmed Case Has Confirmatory Basis
A case classified "confirmed" must carry a confirmation method / lab basis consistent with the condition's surveillance case definition.
Birth Date Before Onset Date
The patient birth date cannot be after the illness onset date.
Notification Sent Within Required Window(report_date)
Case notifications must be transmitted to CDC within the cadence required for the condition (commonly within 7 days, sooner for urgent conditions).
No Duplicate Case Notifications(local_record_id)
The local record id (jurisdiction + local case id) must be unique; duplicate notifications double-count cases in national surveillance.
Patient Age Is Plausible(patient_age_years)
Patient age in years (when reported in years) must fall between 0 and 130.