Developing a Methodology for Real Time Tracking of Heat Related Morbidity Counts in Maricopa County
Methods: Total weekly hospital visits and HRM-associated visits were extracted from hospital discharge data (HDD) for January 2006 through December 2012. The R statistics package was used to determine the expected levels of HRM visits to total visits and establish a baseline and epidemic threshold. Data from 2006-2007 were used as a reference data set and the model was applied to 2008-2012. Alarms were triggered when the proportion of HRM visits exceeded the expected baseline and the epidemic threshold.
Results: A total of 11,698,199 hospital visits occurred during the study period. The HRM rate was 84.13/100,000 visits; 95%CI (82.47-85.79), and seasonally ranging from 5.68; 95% CI (4.22-7.14) in January to 300.37; 95%CI (289.26-311.48) in summer months. Numbers of HRM remained below the epidemic threshold during the study period but several alarms were produced when the numbers of HRM exceeded the expected baseline, even during years with lower rates.
Conclusions: Time-series methods are useful and sometimes necessary for aberration detection. These methods are especially useful for seasonal data and to identify aberration during low-rate periods often missed by methods that ignore the temporal dimension.
Learning Areas:Biostatistics, economics
Environmental health sciences
Systems thinking models (conceptual and theoretical models), applications related to public health
Explain the methodology for identifying the baseline levels and epidemic thresholds of heat-related morbidities. Describe the usefulness of time-series methods for aberration detection.
Keyword(s): Climate and Health, Environmental Health
Qualified on the content I am responsible for because: I worked closely with the first author of this abstract in developing an enhanced methodology for real time counting of heat related illnesses.
Any relevant financial relationships? No
I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.