Statistical Report on Diagnoses of C. difficile and Deaths among Patients with C. difficile

Statistical Report on Diagnoses of C. difficile and Deaths among

Patients with C. difficile Chris Robertson

Strathclyde University Health Protection Scotland

May 09, 2012 1

Outline• Aims and Methods• Diagnoses of C. difficile

– Comparison of wards and periods • Testing for C. difficile

– Where and when was testing taking place• Rates of new diagnoses per 1000 occupied bed days

– Comparison of wards and periods • Funnel plots to compare wards• Death Rates among patients with C. difficile

– All cause deaths and deaths where C. difficile is a contributory cause• Control Charts

– Were the number of cases per week typical• Potential Outbreak Analysis*

– Number of cases in a ward at the same time *

• Trends in C. difficile reports over time *

May 09, 2012 2* At request of Vale of Leven Inquiry Team

Aims

• Investigate pattern of Diagnoses of C. difficile and the extent to which the pattern varies over wards and time

• Investigate pattern of Testing for C. difficile and the extent to which the pattern varies over wards and time

• Investigate pattern of Deaths and report on the extent to which the pattern varies over the wards and period

May 09, 2012 3

Aims and Methods

Methods

• The rate of occurrence of events or the proportion of patients with an event, which require the use of an appropriate denominator.

• In some instance the denominator will be– the number of patients with C. Difficile, – the number tested for C. Difficile, – the number of occupied bed days.

• The latter denominator is required for comparison of wards as the wards are of different sizes.

May 09, 2012 4

Aims and Methods

Methods

• Analysis of rates is based upon the Poisson distribution– Assessed using standard methods– residual plots and index of dispersion test

• Comparison of proportions– Fisher’s exact test and exact binomial confidence

intervals• Time to event analysis

– Cox regression

May 09, 2012 5

Aims and Methods

Study Period• 3 periods of particular interest:

– January to June 2007, – July to November 2007 and – December 2007 to June 2008

• The latter period is the period most under scrutiny

• January to June 2007 is the period which is most directly comparable (temporally) to the main study period

May 09, 2012 6

Aims and Methods

Distribution of new diagnoses of C. difficile over time and ward

• Generally the ward of sample collection is the same the same ward that the result is returned to but not always – Due to patient movement– Admissions – Transfers from and to another hospital

• 2 views– By ward the sample was collected from– By ward the positive result was returned to

• Descriptive analysis of where in the hospital C. difficile was present

May 09, 2012 7

New diagnoses of C. difficile

New and Repeat InfectionsNegative Test was negative

Positive First Test was positive for C. difficile and this was the first positive test for the patient. The patient may have had prior negative tests

Positive Continuation Test was positive for C. difficile and in the previous 28 days the patient has had a positive test result. The patient may have had prior negative tests

Positive Subsequent(Assumed to be a new infection)

Test was positive for C. difficile and in the previous 28 days the patient has not had any positive test results. The patient will have had at least one prior positive test result and may have had prior negative tests

May 09, 2012 8


All New Diagnoses of C. difficile by ward of diagnosis

May 09, 2012 9

Date: 01/01/2007 - 30/06/2008

Wa

rd

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

14

15

3

4

5

6

F

HDU

C Diff All New Diagnoses

Black spots are the first positive test; green dots are a presumed new infection in a patient previously positive for C. difficile. Diagnoses from RAH, WIG, Home or community are excluded


All New Diagnoses of C. difficile by ward of sample collection

May 09, 2012 10

Black spots are the first positive test; green dots are a presumed new infection in a patient previously positive for C. difficile. Diagnoses from RAH, WIG, Home or community are excluded

Date: 01/01/2007 - 30/06/2008

Wa

rd

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

14

15

3

4

5

6

F

HDU

MAU

C Diff All New DiagnosesWard Sample Colleced From


Summary – New Diagnoses

• C. difficile is present throughout the whole period from January 2007 to June 2008,– Especially in Wards 6, 14 and 15.

• This presentation does not take into account ward size or occupancy.

• Little difference between results presented by ward of sample collection and ward result reported to and most subsequent analysis is based upon ward of report

May 09, 2012 11


Testing for C. Difficile by ward and time

• The aim of this section is to see if testing is spread throughout all the wards or is localised to a few wards or a specific period

• Examples from 3 wards

May 09, 2012 12

Testing for C. difficile

May 09, 2012 13


Positive Continuation: Previous positive result may have been in another wardPositive Subsequent: Previous first diagnosis may have been in another ward

May 09, 2012 14


May 09, 2012 15

Summary: testing for C. difficile throughout the whole period in virtually all wards but especially in 14, 3, 5, 6, F and CCU/HDUEven in wards with few cases


Summary

• Testing throughout the whole period in virtually all wards but especially in – 14, 3, 5, 6, F and CCU/HDU.

• This presentation does not take into account ward size or occupancy – 6, 14 and 15 with 19, 22 and 23 beds occupied on

average; – 3, 5, F, Fruin are smaller at 17, 14, 15, 12 beds – CCU/HDU at 9 beds.

May 09, 2012 16


Rates of C. difficile

• Rates per 100 occupied bed days so that comparisons of wards and periods are referred to a common baseline

• Aim• Is there any evidence that the rate of new

diagnoses varies– over period– over ward

May 09, 2012 17

Rates of C. Difficile per 1000 occupied bed days

Rates of new C. difficile infections per month

May 09, 2012 18

Month

Rat

e pe

r 10

00

04

8

Ja7 Ma7 Ma7 Ju7 Se7 No7 Ja8 Ma8 Ma8

Ward 14

Month

Rat

e pe

r 10

00

04

8


Ward 15

Month

Rat

e pe

r 10

00

04

8


Ward 3

Month

Rat

e pe

r 10

00

04

8Ja7 Ma7 Ma7 Ju7 Se7 No7 Ja8 Ma8 Ma8

Ward 5

Month

Rat

e pe

r 10

00

04

8


Ward 6

Month

Rat

e pe

r 10

00

04

8


Ward CCU/HDU

Month

Rat

e pe

r 10

00

04

8


Ward F

Month

Rat

e pe

r 10

00

04

8


Ward Fruin

Ja7 is January 2007, Ja8 January 2008. Occupied beds days data is not available for every day and imputed values are used when necessary. The horizontal dotted blue line is the average rate of new infections per week in the hospital over the whole study period. The vertical green dotted lines separate the time axis into the three periods.


C Difficile Rates by Ward

May 09, 2012 19

No significant difference between the two periods, Jan to May 2007 and Dec-Jun 2008, p = 0.59

Significant differences between the wards, p < 0.0001

The dot is the rate and the horizontal line represents the 95% confidence interval for the rate. The rates are derived from a Poisson regression model adjusting for ward and period (Jan to Jun 2007 and Dec 2007 to June 2008)


Summary – Rates• Ward F has two clear peaks in April/May 2007 and

January/February 2008. • The double peak is also visible in ward 3 while the 2008

peak is visible in ward 6. • The April 2007 peak can be identified in ward CCU(4)/HDU. • Wards 5, 14 and 15 have fairly constant rates• Rate of C. difficile infections varies among the three

periods, p = 0.010. – The rates in the period Jul to Nov 2007 are 45% (95% CI 10%,

67%) lower than those in the first period (Jan to Jun 2007).• No difference in rates between Jan to Jun 2007 and Dec

2007 to June 2008

May 09, 2012 20


Funnel Plots

• Funnel plots show the anticipated variation in the rates of new infections among the wards.

• Aim of this section is to see if there is evidence that the rates of diagnoses of C. difficile in a ward are higher or lower than the average in the hospital taking into account– the natural variation you would expect by chance,

and – the size of the wards as measured by occupied bed

days.

May 09, 2012 21

Funnel Plots of Rates of C. Difficile

Monitoring

May 09, 2012 22

Funnel Plots – what variations should you expect if the rate is the same in all wards

Bed Occupancy increased? – one month extra observation time in latter period

No cases in Fruin Jan 2007-June 2007


Summary Funnel Plots• In the first two periods there is no evidence that any ward

has substantially higher rates of C. difficile with regard to the others, – though ward 15 and Fruin have lower rates in the first period.

• In the last period December 2007 to June 2008, – Ward 6 has higher rates than the others, – ward 5 and Fruin have lower, – and all are outside the 95% funnel plot limits for the size of the

ward. • Assuming that the Poisson model is valid this suggests that

there may be more variability among the wards than could reasonably be attributed to chance (at the 95% confidence limits).

May 09, 2012 23


Deaths

• Is there evidence that the rate of death among patients who were diagnosed with C. difficile vary– over ward, and– over period.

May 09, 2012 24

Death Rates

All Cause Deaths• There are 130 C. difficile patients and for 80 there is a record of

death.• Death Rate is 61.5% (95% CI 52.6%, 69.9%)

– percentage of patients who had C. Difficile who died• Of the 80 patients who died,

– 25% died within 6 days of the confirmed diagnosis being reported to the ward,

– 50% within 17 days, – 75% within 2 months and – 90% within 4 months.

• Three patients died on the day of report and 7 died before the report came back to the ward (1 with a 3 day gap, and 3 with gaps of 2 days, 3 with gaps of 1 day) – the sample was collected while the patients was alive but the patient died before the laboratory reported.

May 09, 2012 25

Death Rates

There is a great deal of variation – some wards had few C Difficile patients, but no statistically significant differences, p=0.14

May 09, 2012 26

Ward of Diagnosis Ward Sample Collected From

Ward Total Dead Percent Lower Upper Total Dead Percent Lower Upper

3 20 14 70.00 45.72 88.11 19 13 68.42 43.45 87.42

4 5 3 60.00 14.66 94.73 6 4 66.67 22.28 95.67

5 9 2 22.22 2.81 60.01 7 1 14.29 0.36 57.87

6 33 20 60.61 42.14 77.09 31 20 64.52 45.37 80.77

14 17 10 58.82 32.92 81.56 17 11 64.71 38.33 85.79

15 11 10 90.91 58.72 99.77 11 9 81.82 48.22 97.72

F 16 9 56.25 29.88 80.25 17 8 47.06 22.98 72.19

Fruin 2 2 100.00 15.81 100.00 2 2 100.00 15.81 100.00

HDU 4 3 75.00 19.41 99.37 3 2 66.67 9.43 99.16

MAU 5 3 60.00 14.66 94.73

Total 117 73 62.39 52.96 71.18 118 73 61.86 52.47 70.65

Death Rates

Percentages of Patients with C. difficile who died by Ward

No statistically significant differences, p=0.73

Period Total Dead Percent Lower Upper

Jan-Jun 200753 31 58.49 44.13 71.86

Jul-Nov 200719 11 57.89 33.50 79.75

Dec-Jun 200858 38 65.52 51.88 77.51

May 09, 2012 27

Death Rates

Percentages of Patients with C. difficile who died by Period

Percentages of Patients with C. difficile dying within 30 days by Ward

There is a great deal of variation – some wards had few C Difficile patients, but no statistically significant differences, p=0.75

May 09, 2012 28

Death Rates

Ward Total Dead Percent Lower Upper Total Dead Percent Lower Upper3 20 9 45.00 23.06 68.47 19 8 42.11 20.25 66.504 5 2 40.00 5.27 85.34 6 2 33.33 4.33 77.725 9 1 11.11 0.28 48.25 7 1 14.29 0.36 57.876 33 13 39.39 22.91 57.86 31 12 38.71 21.85 57.81

14 17 6 35.29 14.21 61.67 17 7 41.18 18.44 67.0815 11 6 54.55 23.38 83.25 11 6 54.55 23.38 83.25

F 16 6 35.29 14.21 61.67 17 5 29.41 10.31 55.96Fruin 2 1 50.00 1.26 98.74 2 1 50.00 1.26 98.74HDU 4 1 25.00 0.63 80.59 3 1 33.33 0.84 90.57MAU 5 2 40.00 5.27 85.34Total 117 45 38.46 30.15 47.51 118 45 38.14 29.88 47.14

Ward of Diagnosis Ward Sample Collected From

Percentages of Patients with C. difficile dying within 30 days by Period

No statistically significant differences, p=0.45

May 09, 2012 29

Death Rates

Total Dead Percent Lower UpperJan-Jun 2007 53 18 33.96 21.52 48.27Jul-Nov 2007 19 5 26.32 9.15 51.20Dec-Jun 2008 58 24 41.38 28.60 55.07

Cause of Death of the 60 patients who had a diagnosis of a new infection of C. difficile between

December 1st, 2007 and 30th June 2008 Ward Diagnosis reported to Ward Sample Collected From Dead Dead

Ward Total Alive

C Difficile not a contributory cause

C Difficile a contributory cause

Percent C Difficile contributory cause Lower Upper Total Alive

C Difficile not a contributory cause

C Difficile a contributory cause

Percent C Difficile contributory cause Lower Upper

3 8 2 1 5 62.5 24.5 91.5 7 2 1 4 57.1 18.4 90.14 2 0 1 1 50.0 1.3 98.7 2 0 0 2 100.0 15.8 100.05 2 1 0 1 50.0 1.3 98.7 1 0 0 1 100.0 2.5 100.06 16 5 3 8 50.0 24.7 75.3 14 4 4 6 42.9 17.7 71.114 8 2 2 4 50.0 15.7 84.3 7 1 2 4 57.1 18.4 90.115 5 0 0 5 100.0 47.8 100.0 6 1 0 5 83.3 35.9 99.6F 9 5 1 3 33.3 7.5 70.1 8 5 1 2 25.0 3.2 65.1Fruin 2 0 0 2 100.0 15.8 100.0 2 0 0 2 100.0 15.8 100.0HDU 1 1 0 0 0.0 0.0 97.5 1 1 0 0 0.0 0.0 97.5MAU 4 1 1 2 50.0 6.8 93.2

7 patients with unknown ward of diagnosis excluded 8 patients with unknown ward of collection excluded

May 09, 2012 30

No evidence that having C. difficile as a contributory cause of death is related to the ward of collection of the sample, p=0.31, or ward of diagnosis, p = 0.29.

Death Rates

Summary - Deaths• There is no evidence that the percentage of C. difficile

patients who died varied over period or ward.• There is no evidence that percentage of C. difficile

patients who died with C. Difficile is a contributory cause varied over ward in the period December 2007 to June 2008.

• Analysis takes into account, age and gender and time to death from first diagnosis but does not adjust for co morbidity of patient

• The relatively small sample size and large number of wards make it difficult to detect differences unless they were very large.

May 09, 2012 31

Death Rates

Control Charts for new infections• In this section the use of elementary control charts on

the weekly new notifications of C. difficile infections per ward is investigated.

• The aim is to see if or when there would have been statistical evidence suggesting that there were an exceptionally large number of C. difficile cases in the hospital i.e. exploratory.

• The study period is divided into two separate periods– Jan-Nov 2007 and Dec 2007 to Jun 2008.

• The main focus is the period Dec 2007 to Jun 2008 and data from the earlier period is used to set the baseline control limits.

May 09, 2012 32

Control Charts

Control Charts Dec 2007-Jun 2008

May 09, 2012 33

The mean number of new diagnoses of C. difficile in patients residing in the hospital from the period Jan to Nov 2007 is used to construct the control chart – 1.69 per week. In the period Dec 2007 to Jun 2008 there are two instances where the statistical process control methods signal - the week beginning 21 January 2008 and the week beginning 28 April 2008

Control Charts

Control Charts - Summary

• Using the period January 2007 to November 2007 to set the baseline, there is evidence of 2 periods of a large number of new diagnoses of C. difficile in the hospital than would be expected by chance

• Conclusions unchanged when using the period January to June 2007 as baseline

• Analysis is retrospective and does not reflect the situation which would have been observed as the data evolved prospectively

May 09, 2012 34

Control Charts

Potential Outbreaks of C. difficile

• During the period Jan 2007 to June 2008 guidelines for defining the occurrence of an outbreak existed.

• Aim of this investigation is to see if there were any dates when an outbreak may have occurred.

• Investigation carried out at the request of the Vale of Leven Hospital Inquiry team

May 09, 2012 35

Potential Outbreaks

Potential outbreaksGeneric Two or more linked cases (or isolates) of unexplained

illnesses which indicates the possibility that they may be due to a known or unknown infectious agent identified in health care premises

Gastrointestinal Three or more cases, with two or more episodes of unexplained vomiting and/or diarrhoea, within a 24 hour period in healthcare premises

May 09, 2012 36

NHS Greater Glasgow and Clyde Control of Infection Committee Policy. Outbreak Policy for outbreaks in healthcare premises. Effective from July, 2006; Review Date July 2010; Replaces previously issued outbreak policies

Potential Outbreaks

Re - creation of C. difficile burden in hospital - Assumptions

• A patient with C. difficile has it for 7 days (range 3-10) following any positive test, not just the first positive test.

• Movement of patients between wards and transfers out and death taken into account

• Analysis is fraught with difficulties because of the lack of absolute certainty in the data. – Although the ward to which the diagnosis was reported is

known there is no guarantee that the patient remained in the same ward for the subsequent 7 days if there is no mention of death, discharge, transfer out to another hospital or movement to another ward.

– analysis is the weakest and the one which is most sensitive to the data quality.

May 09, 2012 37

Potential Outbreaks

May 09, 2012 38

1 2 3 4 5 6 7 8 9 10 11Day

Ward A

Same ward for all 7 days – No subsequent positive test

Ward A

Same ward - subsequent positive test on day 3

Ward A

Same ward - Died or transferred out on day 4

Denotes patient with C. difficile diagnosis on ward

Potential Outbreaks

Example Patient Trajectories

May 09, 2012 39

1 2 3 4 5 6 7 8 9 10 11Day

Ward A

Ward B

Moved ward day 3 - No subsequent positive test

Ward A

Ward B

Moved ward day 3 - subsequent positive test day 7, died day 10, moved back to original ward day 10

Potential Outbreaks

Example Patient Trajectories

May 09, 2012 40

1 2 3 4 5 6 7 8 9 10 11Day

Patient A

Patient B

Moved ward day 3, returned day 6

Potential Outbreaks

Example Ward Trajectories

Patient died on 5th day post diagnosis

1 1 2 1 1 2 2 0 0 0 0Number of Positive patients in ward

Estimated numbers of C. difficile Patients in the hospital per day

May 09, 2012 41

Seldom is there a period with no C. difficile cases in the hospital, 29% of the whole period

Potential Outbreaks

Potential Outbreaks in the wards

May 09, 2012 42

Potential Outbreaks

A black spot corresponds to an occasion when there are 2 patients with C. Difficile in the ward on the same date;

A red spot corresponds to 3 or more patients.

No episodes were observed in the wards not listed in the graphs.

Potential outbreaks in the wards3 day period after positive test

May 09, 2012 43

A black spot corresponds to an occasion when there are 2 patients with C. Difficile in the ward on the same date;

A red spot corresponds to 3 or more patients.

No episodes were observed in the wards not listed in the graphs.

Potential Outbreaks

Outbreak - Summary

• Analysis sensitive to assumptions and data quality

• Evidence of instances where potential outbreaks are possible even with most favourable conditions (1 day post diagnosis)– Both in the January to June 2007 and in the

December 2007 – June 2008 period

May 09, 2012 44

Potential Outbreaks

Comparison with C. difficile cases prior to 2007

• Investigation carried out at the request of the Vale of Leven Hospital Inquiry team

• This investigation is likely to be subject to ascertainment bias due to– Introduction of mandatory reporting of C. difficile

cases from September 2006 onwards– More detailed investigation of hospital and

laboratory data in the period January 2007 – June 2008

May 09, 2012 45

Time Trends

New Reports of C. difficile from 2003 to June 2008

• Data were collected as part of a police investigation and were typed into a spreadsheet from the Vale of Leven infection control team records.

• Potentially useful for describing the historical trends in the numbers of cases of C. difficile in the Vale of Leven Hospital prior to the period under investigation in this report.

• Comparisons of the early with cases from 2007 onwards must always bear in mind that mandatory reporting of all cases of C. difficile in patients over 65 was established as from 1st September 2006.

• With mandatory reporting came – a national case definition, – rules for case finding and definitions; – reporting practices prior to September 2006 may not be comparable

with reporting practices after this period.

May 09, 2012 46

Time Trends

New Reports of C. difficile from 2003 to June 2008

• In the period 2003-2006 there were on average 2.3 new patients with C. difficile per year– some evidence of an increasing trend, p = 0.042– rates increasing by 19.7% (95% CI 0.7%, 42.3%) per year.

• In the three periods which were wholly after the introduction of mandatory reporting for C. difficile among those aged 65 or over there was a big increase in the rates of new patients per month, p < 0.0001, adjusting for trend

May 09, 2012 47

Time Trends

Summary – 2003-June 2008

• It is not easy to interpret the increase in rates as mandatory reporting was introduced in September 2006– part of the increase may be due to changes in

reporting and ascertainment practices. – Part of the increase may also be associated with a

continuation of the increasing trend from 2003 to 2006.

May 09, 2012 48

Time Trends

Summary - Data• There are data issues. • There were rather a large number of data corrections and this

leads to a reduction in confidence in the data. • Some of the problems will stem from data recording issues in

case notes and missing information in cases notes. • The database in the legal office was not set up for a rigorous

analysis as much information was contained within the same text entry field.

• Patient movement data may not be complete• Not absolutely certain that the database for the trend

analysis had all cases of C. difficile, – testing regime may have been different 2007 onwards

May 09, 2012 49

Summary

Summary C. Difficile Cases• C. Difficile is present throughout the whole period from

January 2007 to June 2008 notably in in Wards 6, 14 and 15.

• Using data from Jan – Jun 2007 and Dec 2007-Jun 2008 – there are higher rates of new C. Difficile infections in wards 6

and F, – no differences in the rates between the two periods.

• The funnel plot analysis suggested that in the last period December 2007 to June 2008 the level of variation among the wards was greater that anticipated: – Ward 6 had higher rates of new C. Difficile infections than the

other wards and ward 5 had lower rates.

May 09, 2012 50

Summary

Summary Deaths

• No statistical evidence that the proportion of C. Difficile patients who died varies significantly over the wards.

• No statistical evidence that the proportion of C. Difficile patients who death was associated with C. Difficile varied significantly over the wards in the Dec 2007 to June 2008 period.

• There was no evidence that the proportion of C. Difficile patients who died varied over the three periods.

• From a statistical perspective there are few C. Difficile patients and this contributes to the lack of precision in the estimates and a reduced power for the tests.

May 09, 2012 51

Summary

Summary - Outbreaks

• It seems likely, even allowing for caveats in the data, that there have been a number of occasions, in the periods January-June 2007 and Dec 2007- June 2008 especially, when there were 3 or more patients with C. Difficile in a ward at the one time.

May 09, 2012 52

Summary

Summary Trends

• Increasing rate of cases in the period 2003-2006.

• In Jan-June 2007 and Dec 2007 – June 2008 there were more cases per month than that predicted by the continuation of the increasing trend

• Unknown impact of introduction of mandatory reporting of C Difficile among patients 65+ and possible ascertainment bias

May 09, 2012 53

Summary

May 09, 2012 54

Extra slides showing simulation results

• Even when the length of time a patients is assumed to have C. difficile is varied there is never an occassion when there is not at least one instances with at least 3 patients in a ward on the same day with C. Difficile.

May 09, 2012 55

0 2 4 6 8 10

W.6

010

00

W.5

060

0

0 1 2

W.other

060

0

0

W.HDU

060

0

2 4 6 8 10 13 16

W.F

080

0 1

W.3

060

0

3 4 5 6 7

W.14

020

0

0 1 2 3 4

W.150

300

0

W.4

060

00

W.Fruin

060

0

Assumed a case for 3 - 10 days

3+ cases in a day

17 22 27 32 37 42

W.6

040

800

W.5

060

0

7 10 14 18 22 26

W.other

060

0 1

W.HDU

060

0

15 19 23 27 31 35 39

W.F

060

5 7 9 12 15 18 21

W.3

060

3 5 7 9 11 14 17

W.14

080

3 4 5 6 7 8 9 10

W.150

150

0

W.4

060

00

W.Fruin

060

0


2+ cases in a day

1 3 5 7 9 12 15 19

W.6

010

00

W.5

060

0

2 3 4 5 6 7 8 9 11

W.other

010

0

0

W.HDU

060

0

4 6 8 10 13 16

W.F

010

0

1 2 3 4 5 6 7 8 9

W.3

015

0

1 2 3 4 5 6 7

W.14

020

0

1 2 3 4 5

W.150

200

0

W.4

060

00

W.Fruin

060

0


2+ cases in a day

0 1 2

W.6

040

00

W.5

060

0

0

W.other

060

0

0

W.HDU

060

0

0 1 2 3 4

W.F

020

0

0

W.3

060

0

1 2 3 4 5

W.14

020

0

0

W.150

600

0

W.4

060

00

W.Fruin

060

0


3+ cases in a day

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Statistical Report on Diagnoses of C. difficile and Deaths among Patients with C. difficile

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