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Meningococcal disease and the law: does non-notification really happen?
1Department of Paediatrics, School of Medicine, University of Melbourne, Parkville, Victoria.
Abstract:
In Victoria, legislation clearly makes the notification of clinical or confirmed cases of meningococcal disease mandatory. Statistical modelling suggests that meningococcal disease is significantly under-notified, and that incorrect codes might be being ascribed to some in-patient episodes. The aims of this study were (i) to test the assumption that cases identified as non-notified cases were true cases, and (ii) to identify the reasons for non-detection on the hospital separation database and non-notification to the infectious diseases unit. Of 26 cases not identified on the in-patient dataset, the main causes were either being given completely incorrect ICD-9-CM codes (11 cases) or being given codes for a different type of meningitis (8 cases). Of 29 non-notified admissions, most were clinically (17) or microbiologically (6) confirmed cases, although 5 were coded in error and were not cases of meningococcal disease. Therefore, although the allocation of incorrect ICD-9-CM codes at separation was a major reason for discrepancy, non-notification was a real and recent problem. It is also possible that some clinical staff did not understand the relationship between Neisseria meningitidis and meningococcal disease, the public health implications of this infection, or the law relating to it.
Insights
Meningococcal disease in Victoria is under-reported due to incorrect medical coding and non-notification. This study found significant discrepancies in case identification and reporting, highlighting a real public health issue.
Area of Science:
- Public Health
- Infectious Diseases
- Health Informatics
Background:
- Legislation in Victoria mandates reporting of meningococcal disease cases.
- Statistical modeling indicates significant under-notification of meningococcal disease.
- Incorrect coding of inpatient episodes may contribute to under-reporting.
Purpose of the Study:
- To validate cases initially identified as non-notified.
- To determine reasons for non-detection in hospital databases.
- To identify causes of non-notification to infectious disease units.
Main Methods:
- Review of 26 cases not found in the inpatient dataset.
- Analysis of 29 non-notified admissions.
- Investigation of coding errors and diagnostic discrepancies.
Main Results:
- Incorrect ICD-9-CM codes were assigned in 11 cases, and codes for other meningitis types in 8 cases, leading to non-detection.
- Most non-notified admissions (17 clinical, 6 microbiological) were confirmed meningococcal disease cases.
- Five non-notified admissions were miscoded and not meningococcal disease cases.
Conclusions:
- Incorrect ICD-9-CM coding is a major factor in meningococcal disease under-notification.
- Non-notification of confirmed cases remains a significant and current problem.
- Lack of understanding regarding Neisseria meningitidis, its implications, and reporting laws may contribute to non-compliance.
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