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Comparison of Maryland hospital discharge and trauma registry data
Melissa Lee McCarthy1, Andrew D Shore, Tracey Serpi
1Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA. mmccarth@jhmi.edu
Background:
This study aimed to examine the validity of using Maryland hospital discharge data to characterize injuries sustained by trauma patients.
Methods:
Maryland hospital discharge and Maryland trauma registry data for 1999 were merged, and the extent of agreement regarding the presence and severity of injuries sustained was evaluated.
Results:
The mean Injury Severity Score was 8.4 according to the Maryland hospital discharge data and 10 according to the Maryland trauma registry data (p < 0.0001). The Maryland hospital discharge data identified 95% or more of all moderate to severe injuries (Abbreviated Injury Score, > or =2) for all body regions except the head. There was substantial agreement between the two data sets for mechanism of injury (weighted kappa, 0.62), the number of preexisting conditions present (weighted kappa, 0.45) and final disposition (weighted kappa, 0.78).
Conclusions:
The Maryland hospital discharge data are a valid source for documenting the nature and severity of injuries sustained by trauma patients, except for those with a relatively minor head injury.
Insights
Maryland hospital discharge data accurately identifies most trauma injuries, except minor head injuries. This study validates its use for characterizing injury severity and patient outcomes.
Area of Science:
- Trauma research
- Health services research
- Injury surveillance
Background:
- Characterizing trauma patient injuries is crucial for effective healthcare.
- Hospital discharge data is a potential source for injury information.
- The validity of using Maryland hospital discharge data for trauma injuries requires examination.
Purpose of the Study:
- To assess the accuracy of Maryland hospital discharge data in describing trauma patient injuries.
- To compare injury severity metrics between hospital discharge data and trauma registry data.
- To evaluate the agreement on injury characteristics and patient disposition.
Main Methods:
- Merging Maryland hospital discharge data with Maryland trauma registry data from 1999.
- Comparing the presence and severity of injuries recorded in both datasets.
- Utilizing statistical measures like the Injury Severity Score and weighted kappa coefficients.
Main Results:
- A statistically significant difference in mean Injury Severity Score (ISS) between the two datasets (8.4 vs. 10, p < 0.0001).
- Maryland hospital discharge data captured over 95% of moderate to severe injuries (Abbreviated Injury Score >= 2) across most body regions, excluding the head.
- Substantial agreement was found for mechanism of injury (kappa=0.62), comorbidities (kappa=0.45), and disposition (kappa=0.78).
Conclusions:
- Maryland hospital discharge data serves as a valid resource for documenting the nature and severity of trauma-induced injuries.
- The data is particularly effective for moderate to severe injuries across most body regions.
- An exception is noted for minor head injuries, which may be underrepresented or mischaracterized.
