Table 1 Attributes included in the development of a classifier for statistical alarms recorded by a PHE multi-system syndromic surveillance service
From: Machine learning to refine decision making within a syndromic surveillance service
Field Name | Description | Entries | Missing | Unique | Ip | Values | p-value |
|---|---|---|---|---|---|---|---|
Class Variables | |||||||
Decision | Decision taken by syndromic surveillance analyst | 592 | 66,913 | 3 | 1.0000 | Alert, Monitor, No-action | – |
Attribute Variables; from event | |||||||
Year | Year of the alarm | 67,505 | 0 | 3 | 0.0001 | 2013, 2014, 2015 | 9.7 × 10−2 |
Q | Quarter | 67,505 | 0 | 4 | 0.0002 | Jan-Mar, Apr-Jun, Jul-Sep, Oct-Dec | 3.3 × 10−2 |
D | Day of the week | 67,505 | 0 | 7 | 0.0006 | Sun, Mon, Tue, Wed, Thu, Fri, Sat | 6.9 × 10−8 |
Alarm | Was the event a statistical alarm? | 67,505 | 0 | 3 | 0.0014 | Yes, No, Unknown | < 10−10 |
System | The system that alarmed | 67,505 | 0 | 5 | 0.0006 | NHS111, NHS24, EDSSS, GPOOHSS, or GPIHSS | 4.4 × 10−9 |
IndicatorS | Indicator that alarmed | 67,505 | 0 | 53 | 0.0041 | 1 of 53 different syndromes | < 10− 10 |
IndicatorG | Coarse grained version of IndicatorS | 67,505 | 0 | 8 | 0.0013 | Cardiac, Impact of Cold, Gastrointestinal, Impact of Heat, Influenza-like illness, Respiratory, Other & Unspecified | < 10− 10 |
IndicatorP | Specific/general indicator | 67,505 | 0 | 2 | 0.0001 | specific, General | 2.0 × 10−3 |
IndicatorL | Indicator severity | 67,505 | 0 | 5 | 0.0002 | Consultation, Admitted, Severe, High Dependency Unit/Intensive Care Unit, Mortality | 1.0 × 10−10 |
Region | PHE Region | 67,505 | 0 | 13 | 0.0037 | 1 of 13 PHE regions | < 10−10 |
LocationP | Geography of alarm | 67,505 | 0 | 3 | 0.0037 | Local, Regional, National | < 10−10 |
Experience | Is syndromic surveillance analyst experienced? | 67,505 | 0 | 2 | 0.0001 | Yes, No | 2.1 × 10−2 |
Attribute Variables; from first stage risk assessment | |||||||
Excess | Size of the alarm | 66,406 | 1099 | 4 | 0.0115 | 0,1,2,3 | < 10−10 |
Repeated | Is the alarm a repeat? | 65,766 | 1739 | 4 | 0.0026 | 0, 1,2,3 | < 10−10 |
Multi-system | Is the alarm in multiple systems simultaneously? | 65,742 | 1763 | 4 | 0.0094 | 0,1,2,3 | < 10−10 |
Nattrend | Is the alarm counter to the national trend? | 65,771 | 1734 | 4 | 0.0003 | 0,1,2,3 | 2.3 × 10−5 |
Score1 | Sum of scores from first stage risk assessment | 65,795 | 1710 | 13 | 0.0277 | 0–12 | < 10−10 |
BInitial | Does first stage analyst engage consultant epidemiologist to perform second stage? | 67,505 | 0 | 2 | 0.0357 | Yes, No | < 10−10 |
Attribute Variables; from second stage risk assessment | |||||||
Season | Is the alarm counter to the seasonal trend? | 573 | 66,932 | 3 | 0.0258 | Yes, No, Missing | < 10−10 |
Geography | Does the alarm show an atypical geographical clustering? | 572 | 66,933 | 3 | 0.0259 | Yes, No, Missing | < 10−10 |
Age | Is the alarm centred on a particular age group? | 572 | 66,933 | 3 | 0.0264 | Yes, No, Missing | < 10−10 |
Severity | Is there an unusual increase in illness severity associated with the alarm? | 571 | 66,934 | 3 | 0.0259 | Yes, No, Missing | < 10−10 |
BScore | Are the second stage scores subsequently completed? | 67,505 | 0 | 2 | 0.0130 | Yes, No | < 10−10 |
Score2 | Sum of scores from second stage risk assessment | 67,505 | 0 | 15 | 0.0325 | 1–15 | < 10−10 |
Bsummary | Presence of text in summary field | 67,505 | 0 | 2 | 0.0041 | Yes, no | < 10−10 |