# Presentation: 534680

## The Barell Matrix, Updates; 

**TEMR**

**THE  ISRAELI **
**CENTER FOR**

- Limor Aharonson-Daniel, Israel
- Megan Davies, USA

- The Center for Trauma and Emergency Medicine Research,
- Gertner Institute for Epidemiology and Health Policy Research, Israel
- National Center for Injury Prevention and Control,
- Centers for Disease Control and Prevention, Atlanta, GA USA

- The **Barell Matrix**, Updates;
- The Composition of **TBI Rows**
**Multiple Injury Analysis** Using Matrix

**Notes:**
I can not start this presentation without mentioning Vita Barell. Vita was a special person with a great passion for life and compassion for people. As a researcher, Vita was thorough and smart and original in her approach to things when she set her mind on doing something, she would be entirely consumed by it and there was no doubt the goal would be achieved, no matter how far fetched. Such a goal was this matrix. Finishing the matrix was a race against time, Vita knew it for much longer than we were willing to admit it.  We all knew she was sick. Very sick, but when she died, we were caught unprepared.  To me, this matrix is Vitas legacy. So it took a while to get used to making the decisions without getting the feedbacks, I still find myself thinking, Vita would kill me for this once in a while. But her enthusiasm for this project was contagious and  with the support and help of Lois Fingerhut and with the blessing of Ellen Mackenzie, I was able to pick up where she left and finalize this Matrix. Naming the matrix after Vita seemed the natural thing to do. 
Our presentation has three parts.
First, I will update you on the status of the Barell Matrix and on the application of our agreements from last year.
I will conclude with the only issue which is still being discussed – The TBI rows.
Megan Davies of the CDC, will pick up from there and present the concerns of the CDC NCIPC and those expressed by several neurological organizations about the TBI rows of the matrix and its implications for the definition of TBI.
I will then present the issue of multiple injury analysis using the Matrix.
The multiple injury analysis is at it’s very preliminary stages and involves some serious methodological dilemas. I plan to expose some of the weak spots to you, hoping to hear your thoughts and ideas either in the next four days or by e-mail later.

## What is the Matrix?

**The Matrix is a tool for classifying injury ICD-9-CM codes by body region and nature of injury. **
**It is useful for standardized retrieval of injury cases for epidemiological, clinical and management oriented analyses**

**What is the Matrix?**

**Matrix Reminder**

**Notes:**
Just a few words to remind those of you who were not involved closely with the matrix or anybody who was not at the ICE last year. The matrix is a tool...
Matrix objectives were

## Matrix objectives

** ****To characterize the patterns of injury **

**Matrix objectives**

** ****To serve as a standard for casemix comparison **

** ****To simplify the process of classifying injuries**

** ****To provide a standard format for reports**

**Matrix Reminder**

**Notes:**
Were to
To simplify the process of classifying injuries using ICD-9 CM in a trauma setting.
To provide a standard format for reports from trauma registries, hospital discharge data systems, emergency department data systems or other sources of nonfatal injury data. .
Serve as a standard for case-mix comparison across time and place 
Characterize the patterns of injury resulting from diverse circumstances using a manageable number of clinically meaningful diagnostic categories

## Motivation for building the matrix

- Sorted by **nature of injury**

- Detecting injuries by **body region**
- requires collating codes across
- chapters

**ICD 9-CM CODES**** **
**800-995**

**Matrix Reminder**

**Notes:**
The motivation for building the matrix rose from the fact that ICD9 cm codes 800-995 which describe traumatic injuries appear in a thick book sorted by nature of injury.(enter)
Detecting all injuries to the same body region requires collating codes across chapters, leaving room for variation and error.  
For example, if I want to look at lower leg, I may or may not include the knee, while others may choose to do otherwise, resulting in a different population.
This becomes more of a problem when we attempt to do comparative or international studies.

## ICD 9-CM CODES 800-995

**Motivation for building the matrix**

**nature of injury**

**body region**

**Matrix Reminder**

**Notes:**
So we were looking for a way to present codes in a way which would define in a standard fashion both the nature of injury and the body region of the injury. These are the two axes of the matrix.

## The Matrix structure

** **

**Nature of injury**

**Body Region**

- ICD-9-CM injury codes

**Matrix Reminder**

**Notes:**
Matrix columns describe the nature of injury,
Rows detail the body region and matrix cells (enter) 
contain ICD-9-CM injury codes

## Body Region (Rows) are based on :

**Anatomic subgroups**
**High Incidence**
**Variability in Outcome**
**Difference in health care utilization**

**Body Region (Rows) are based on :**

**Matrix Reminder**

**Nature of injury (Columns) are based on**
**Sequence**** ****of codes in ICD-9-CM codebook**

**Notes:**
Nature of injury is described in 12  columns based on the sequence of codes in ICD9CM.  (enter) 
body region was divided into 35 rows.
The subdivision of the rows was based on anatomic subgroups, high incidence, variability in outcome, difference in utilization

## Dissemination

**The Matrix was posted on the net by Lois in October 2001.**

**A paper describing matrix construction will be published in the June 2002 issue of Injury Prevention.**

**Notes:**
Before I go into the details, just two words about the dissemination of this work, 

## General Agreements Reached

- “Five digit ICD-9-CM codes will be used where necessary”.

- “Priority codes will not be used, an “other and unspecified” by body region row will be added in order to minimize loss of information”.

**April 3, 2001: ICE meeting, Washington DC**

**General Agreements Reached**

- “Instructions on how to collapse rows will be available to ensure a standard collapsed table”.

**Notes:**
I will start with quoting our agreements from last year and presenting the actions performed on the matrix in response to these agreements. First Instructions...

## Specific Agreements, 

- ICE meeting, Washington DC, 2001

**Specific Agreements,**** **

## Specific Agreements, 

- ICE meeting, Washington DC, 2001

**Specific Agreements,**** **

## Specific Agreements, 

- ICE meeting, Washington DC, 2001

**Specific Agreements,**** **

## Specific Agreements, 

- ICE meeting, Washington DC, 2001

**Specific Agreements,**** **

## Specific Agreements, 

- ICE meeting, Washington DC, 2001

**Specific Agreements,**** **

- “The matrix has a row for “system wide conditions” enabling use for non traumatic injuries”.

## Specific Agreements, 

- ICE meeting, Washington DC, 2001

**Specific Agreements,**** **

- The split of TBI conventional definition into two rows in the matrix brought about discussions with CDC NCIPC, the American Academy of Neurology and others on TBI definition and separation into several levels of TBI.

## Original TBI definition

**injury to the head that is documented in a medical record, with one or more of the following conditions attributed to head injury: observed or self-reported decreased level of consciousness, amnesia, skull fracture, objective neurological or neuropsychological abnormality, or diagnosed intracranial lesion; **

- Thurman DJ, Sniezek JE, Johnson D, Greenspan A, Smith SM. *Guidelines for Surveillance of Central Nervous System Injury.* Atlanta: Centers for Disease Control and Prevention, 1995.

## Original Two-row TBI definition

**Definite ****TBI**

**Injuries with no mention of intracranial injury or with loss of consciousness of less than one hour****.**

**injuries with a specific mention of intracranial injury  or loss of consciousness of more than one hour**

**Original Two-row ****TBI definition**

**(created by Vita Barell)**

- A derivation from CDC definitions: concussions with no or short loss of consciousness were classified as ‘possible TBI’.

**Possible**** ****TBI**

- An addition to the definition: injuries indicating damage to the optic nerve pathways:
- optic chiasm (950.1)
- optic pathway (950.2) and
- visual cortex (950.3)

**Notes:**
TBI were initially based on the CDC case definition but were split into two groups: definite tbi and possible TBI. The DTBI includes injuries with a specific mention of intracranial injury or loss of consiousness of more than one hour. Possible TBI included cases with skull fratures and no mention of intracranial injury or with a loc of less than one hour. A derivation from CDC definitions were concussions with no or short loc which were classified as ‘possible’. 
These changes started a dialogue with ncipc.

## CDC concerns regarding TBI separation

** **959.01
-  Concussions with no or short LOC
-  TBI with LOC of unspecified duration
-  TBI with unspecified level of consciousness
-  Shaken baby syndrome

**Three-row ****TBI definition**

## Three-row 

**Definite ****TBI**
**Type 1**

**Injuries with no mention of intracranial injury or with no loss of consciousness**

**Injuries with a recorded evidence of an intracranial injury or a moderate or prolonged loss of consciousness (loc).**

**Possible**** **
**TBI**

**Three-row **
**TBI definition**

**Definite ****TBI**
**Type 2**

**Injuries with no recorded evidence of intracranial injury  and loc of less than one hour; loc of unknown duration or unspecified level of consciousness.**
**Concussions.**

## Three-row 

**Definite ****TBI**
**Type 1**

**Injuries with no mention of intracranial injury or with no loss of consciousness**

**Injuries with a recorded evidence of an intracranial injury or a moderate or prolonged loss of consciousness (loc).**

**Possible**** **
**TBI**

**Three-row **
**TBI definition**

**Definite ****TBI**
**Type 2**

**Injuries with no recorded evidence of intracranial injury  and loc of less than one hour; loc of unknown duration or unspecified level of consciousness.**
**Concussions.**

** **959.01      854
-  Concussions with no or short LOC
-  Shaken baby syndrome (995.55)
-  LOC of unspecified duration
-  Unspecified level of consciousness

## Possible TBI

**Probable ****TBI**

**Plausible ****TBI**

**Definite ****TBI ****type 1 (grade 1)**

**Definite ****TBI ****type 2 (grade 2)**

**Definite severe/moderate ****TBI**

**Definite mild ****TBI**

## Three-row TBI

**Three-row ****TBI**

**Notes:**
So this is the current look of the matrix

## Traumatic Brain Injury

**Notes:**
This table presents the severity, inpatient death rate and other characteristics of TBI patients. 
Type 1 DTBI Patients had significantly higher proportion of ISS 25+ (30 vs 1%)
Inpatient death rate was 13% compared with 0.3
These results reinforce the appropriateness of this separation.

## Megan

## Multiple injury

**Multiple injury**
**And the construction of injury profiles**

- The Center for Trauma and Emergency Medicine Research,
- Gertner Institute for Epidemiology and Health Policy Research, Israel

## Summarizing multiple injuries Motivation

**Multiple injury is often associated with greater severity and mortality.**
** ****ISS takes into account the contribution of multiple injuries to severity, but does not profile the injury.**

**Summarizing multiple injuries** **Motivation**

## Summarizing multiple injuries AIMS

**To standardize this method to enable the conduct of comparable studies across populations, time, place etc.**

**Summarizing multiple injuries ****AIMS**

**Notes:**
Our aims were To create a method for presenting aggregated data on injury patterns in populations And (enter)
 To standardize this method to enable the conduct of comparable studies across populations, time, place and so on

## Adam

- Jo

**Fractured ankle**

**Skull fracture, with an intracranial injury**
**Flail chest**

**multiple diagnoses**

**Single diagnosis**

**Notes:**
Adam was in a severe car crash. He has a skull fracture with an intracranial injury and a flail chest. (enter)
Jo was striding along on his scooter as he fell. He fractured his ankle.

## Single diagnosis

**Single diagnosis**

## Summary report 

**Notes:**
This table presents data from the Israeli National Trauma registry for two years, summarized by broad matrix rows (5 groups). We see that ... (describe)

## Summarizing multiple injury diagnostic data

**Select one**** **
**diagnosis**

- first listed/major

**multiple diagnoses**
**patients**

**single diagnosis**
**patients**

**Notes:**
When multiple diagnoses in one patient are present, one option would be to select a diagnosis, either the first listed or the major diagnosis (this is done in the states with Nhds data)

## Limitation of using a Single diagnosis

**Difficulty in assigning the principal diagnosis **

**Limitation of using a Single diagnosis**
**For summarizing multiple injuries**

**Adam**

**Distorts the description of the actual injury**

**Skull fracture, with an intracranial injury**
**Flail chest**

**Notes:**
Choosing a single diagnosis is sometimes impossible. In Adams case for example, it is hard to define which of his injuries (head or chest) are more severe.
Additionally, once the primary diagnosis is selected, the other diagnoses will no longer appear thus the picture we get of the injury is distorted. 

## Distribution of injuries by body region

**Population: ITR Road Traffic Accidents, 1997-2000, total of 17459 patients**

**Distribution of injuries by body region**

**Single or Multiple?**

**Notes:**
The distribution of diagnoses in ITR road traffic accidents for three years from 1997-2000 is presented in this figure.
Please note that this figure presents diagnoses, not individuals. On the horizontal axis we have the body region, on the vertical we have number of diagnoses. Those with only one diagnosis appear in checkered yellow while those with more than one diagnosis will appear in the red. As the figure shows diagnoses, people with multiple diagnoses will appear in more than one bar..
The majority of injuries were to the head or neck followed by injuries to the extremities.
The large proportion of multiples in the population stresses the significance of a good summary methodology.

## Reasons for using multiple diagnoses

- Enable counting all cases with a specific injury
- Reflect the actual injury pattern in the individual
- Often associated with greater severity
- Identification of common profiles of multiple injuries

**Reasons for using multiple diagnoses**
**For multiple injury patients**

**Multiple diagnoses injury profiles**

**Notes:**
The use of multiple diagnoses enables the identification of all cases with a specific injury.
Even if you had another injury, all diagnoses will be kept redlecting the actual pattern of injury in the individual, 
multiple injury it is often associated with greater severity AND it enables the identification of common profiles of multiple injuries.

## Create injury profile

**diagnosis**

- first listed/major

**Create injury profile**

**multiple diagnoses**
**patients**

**Summarizing ****multiple**** injury diagnostic data**

**Notes:**
So it is clear that selecting one diagnosis is not a good option and what we want to do is to create and injury profile
This profile can include one or more diagnoses.  

## Creating injury profiles

**Divide body regions into groups**

**Head and Neck   H**
**Spine and Back   S**
**Torso              T**
**Extremities        E**
**Other              O**

**Notes:**
Stage 1: divide body region into groups
For demonstrating the method, body was split into five regions, this methodology can then be applied to a more detailed division of body regions. 

## Slide 37

**Notes:**
We first printed out all combinations and all those with a % > 1 were chosen for the report.
Combinations with a % smaller than 1 were grouped together

## Frequency distribution of groups

- Head and Neck   H
- Spine and Back   S
- Torso                 T
- Extremities        E
- Other  multiple   O

**Frequency distribution of groups**

**Notes:**
Frequency distribution of each diagnostic group is examined. 
For example, in road traffic accident injuries in Israel, 25% were single injury to the head, 21.5% were extremities and 11.1 % were both head and exremities.

## Characterizing diagnostic groups

**ISS**
**Inpatient death**
**Duration of inpatient stay**
**External cause of injury**
**                               ****etc.**

**Notes:**
Several variables are used to characterize injury profiles. These may include iss, inpatient death, duration of inpatient stay, ...

## Duration of Inpatient stay by diagnostic group combinations

**Legend**
- Head and Neck   H
- Spine and Back   S
- Torso                  T
- Extremities        E
- Other  Multiple   O

- Multiple injuries

- Single injuries

- 75%

- 25%

- Median

**Notes:**
On the horizontal axis we have the injury profile, on the vertical axis we have the number of days. The red dots represent the median and the yellow line is the interquartile range from 25 to 75 percent
The duration of inpatient stay was significantly higher for patients with multiple injury, particularly those with injuries to the head neck extremities and torso with a median of 8 days compared to 2 days for patients who had torso alone or head neck alone.
It is obvious in the graph that patients with multiple injuries (marked with a light square) are those with the longer stays

## Inpatient death by diagnostic group combinations

**4346**

**1935**

**2010**

**922**

**1319**

**1121**

**417**

**3760**

- n

- Multiple injuries

- Single injuries

- Inpatient death

**Notes:**
The injury profile is now on the left hand side and the proportion who died  in hospital is on the horizontal axix
An examination of inpatient death rates showed that death rate increases with an increase in the number of diagnosis
The highest death rate was registered to head neck extremities and torso injuries.

## Slide 42

**Notes:**
Looking into a population of road traffic accidents we can also crosstabulate with external cause of injury

## A technique for analyzing multiple injuries was presented using the Barell diagnostic matrixThe importance of using multiple injury in describing the injured has been demonstrated. Injury profiles enable standardized comparisons of casemix and outcome between external cause of injury, hospitals and countries. Profiles could also serve for efficient staffing of specialists in multidisciplinary trauma teams. 

- A technique for analyzing multiple injuries was presented using the Barell diagnostic matrixThe importance of using multiple injury in describing the injured has been demonstrated. Injury profiles enable standardized comparisons of casemix and outcome between external cause of injury, hospitals and countries. Profiles could also serve for efficient staffing of specialists in multidisciplinary trauma teams.

**Notes:**
A technique for analyzing multiple injuries was presented using the Barell diagnostic matrix
The importance of using multiple injury in describing the injured has been demonstrated on road traffic casualties. Injury profiles enable standardized comparisons of casemix and outcome between hospitals and countries. Profiles could also serve for efficient staffing of specialists in multidisciplinary trauma teams. 

## Problems, Limitations 

**and Unresolved issues**

**Definition of multiple **

**Number of combinations**

**Severity measures **

## Thanks for your attention

**Thanks for your attention**