from data to signals to screenshots: recent developments in nycdohmh ed syndromic surveillance. marc...
TRANSCRIPT
From Data to Signals to Screenshots: Recent Developments in NYCDOHMH
ED Syndromic Surveillance.
Marc Paladini
New York City Department of Health and Mental Hygiene
Questions
• What are we looking for?
• How are we looking for it?
• What do we need to find it?
• What do we do after we find it?
• How does this help us do our job more effectively?
Outline
• Introduction to NYC emergency department syndromic surveillance.– Analysis– Signal Investigation
• Data Visualization
• Future Directions
ED Syndromic Surveillance in NYC
• Chief complaint – hierarchical syndrome coding• Syndromes:
– 1. Sepsis– 2. Respiratory– 3. Rash– 4. Fever– 5. Cold– 6. Diarrhea– 7. Asthma– 8. Vomit– Other
Hospital Statistics - 2005
• 3,136,772 total visits. (7000-10,000 / day)syndrome number percent
other 2351837 74.98%
sepsis 16968 0.54%
respiratory 258946 8.26%
rash 61352 1.96%
fever 184034 5.87%
cold 54387 1.73%
diarrhea 51027 1.63%
asthma 75566 2.41%
vomit 82655 2.64%
Data Analysis
• Ratio of syndrome/other• Citywide and spatial (zip code, hospital)• Age 13+: respiratory and fever• All ages: diarrhea and vomit• Age group
– 0-4– 5-17– 18-59– 60+
• 7 days/week
Syndromic Analyst
• Run surveillance – usually @ 2 hours
• Review output for signals
• Review signal details– Linelist– Baseline vs. signal frequency tables
• Consult with DOH Physician on call (Cluster Doc)
Cluster Doc
• Review data with analyst
• Ask for further details
• Decide on follow up– guidelines/protocol– “fingerprint” of signal
Signals – 2005
syndrome City Hospital Ziprespiratory 17 3 1fever 11 10 7diarrhea 28 8 6vomit 23 10 10
Investigation of Signals
• Review line list• Check complimentary systems• Acquire interim data (12 hour log)• Call to EDs• Chart reviews• Patient follow up (phone calls)• Augment lab testing/collect specimens• On site epi teams• Special studies (case-control)
Routine Steps
• First day (Resp/Fev) vs. 2nd day (Vom/Dia)• Perform descriptive statistics, midday log• Examine CUSUM, other systems• Call hospitals with CUSUM alarms
– What did they see yesterday?– What are the seeing today?– Clinical clusters, unexpected severe illness?– Augment lab testing
• Alert ED staff
Concerning Features of a Syndromic Signal
• Sustained• Multiple hospitals • Large number of excess cases • Uniformity of chief complaints• Young adults or age/sex clustering • Overlapping syndrome signals • Coincident clinician call • Coincident with high profile public event• Concordance with other surveillance systems
Results of Investigations
• Some clear seasonal patterns evident
• Sharp spikes associated with known events
• Rich ecological associations
• Difficult to investigate
• Used to reinforce public health messages (influenza, viral GI, heat wave, blackout, asthma)
Proposed Prospective Investigation Protocol
• All significant resp and fever signals
• Chart reviews
• Patient interviews
• Classify if cases in signal are related– by lab diagnosis, i.e. strep pharyngitis– by clinical diagnosis, i.e. pharyngitis– by risk factor, i.e. subway travel
Fev/resp/resp non-feb
Febrile Respiratory, Fever and Non-febrile Respiratory Syndromes. Weekly ratio. Log Scale.
0.001
0.01
0.1
1
1/5/
2002
2/9/
2002
3/16
/200
24/
20/2
002
5/25
/200
26/
29/2
002
8/3/
2002
9/7/
2002
10/1
2/20
0211
/16/
2002
12/2
1/20
021/
25/2
003
3/1/
2003
4/5/
2003
5/10
/200
36/
14/2
003
7/19
/200
38/
23/2
003
9/27
/200
311
/1/2
003
12/6
/200
31/
10/2
004
2/14
/200
43/
20/2
004
4/24
/200
45/
29/2
004
7/3/
2004
8/7/
2004
9/11
/200
410
/16/
2004
11/2
0/20
0412
/25/
2004
1/29
/200
53/
5/20
054/
9/20
055/
14/2
005
6/18
/200
57/
23/2
005
8/27
/200
510
/1/2
005
11/5
/200
512
/10/
2005
1/14
/200
6
Sum of RRespnofev Sum of Rfevflu Sum of RRfev
Diar/vom age 0-4
Diarrhea and Vomit Syndromes Age 0 - 4. Weekly Ratio.
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
1/5/
2002
2/9/
2002
3/16
/200
24/
20/2
002
5/25
/200
26/
29/2
002
8/3/
2002
9/7/
2002
10/1
2/20
0211
/16/
2002
12/2
1/20
021/
25/2
003
3/1/
2003
4/5/
2003
5/10
/200
36/
14/2
003
7/19
/200
38/
23/2
003
9/27
/200
311
/1/2
003
12/6
/200
31/
10/2
004
2/14
/200
43/
20/2
004
4/24
/200
4
5/29
/200
47/
3/20
048/
7/20
049/
11/2
004
10/1
6/20
0411
/20/
2004
12/2
5/20
041/
29/2
005
3/5/
2005
4/9/
2005
5/14
/200
5
6/18
/200
57/
23/2
005
8/27
/200
510
/1/2
005
11/5
/200
512
/10/
2005
1/14
/200
6
Sum of Rvom Sum of Rdiar
Fev resp/fev cold
Febrile Respiratory and Cold Syndrome Visits.Weekly Ratio.
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
1/5/
2002
2/9/
2002
3/16
/200
24/
20/2
002
5/25
/200
26/
29/2
002
8/3/
2002
9/7/
2002
10/1
2/20
0211
/16/
2002
12/2
1/20
021/
25/2
003
3/1/
2003
4/5/
2003
5/10
/200
36/
14/2
003
7/19
/200
38/
23/2
003
9/27
/200
311
/1/2
003
12/6
/200
31/
10/2
004
2/14
/200
43/
20/2
004
4/24
/200
45/
29/2
004
7/3/
2004
8/7/
2004
9/11
/200
410
/16/
2004
11/2
0/20
0412
/25/
2004
1/29
/200
53/
5/20
054/
9/20
055/
14/2
005
6/18
/200
57/
23/2
005
8/27
/200
510
/1/2
005
11/5
/200
512
/10/
2005
1/14
/200
6
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
Sum of RRfev Sum of RCLD_fev