# Presentation: 672821

## Using and Interpreting Data

- Substance Abuse Epidemiology Unit
- Epidemiology and Response Division
- New Mexico Department of Health

## Outline

- Measures of relative frequency
- Calculating rates
- Examples
- Age-adjustment
- Trends
- Small group exercises
- Sources of data
- Review of the New Mexico State Epi Profile
- Community examples

## Ratios

- Ratio:  a comparison of two groups
- Groups may be unrelated or subgroups of a larger category
- Ratio = A / B
- Examples:  miles / gallon
- 			      students / teacher
-                       males / females (sex ratio)

**Notes:**
A frequency is a count or enumeration.  In order to compare groups, we use relative measures. 
When you look at secondary data in a report or publication, you need to be sure they are using the same measure so that you can compare groups. 

## Proportions

- Proportion:  a relationship of one part to the whole, e.g. percentage, fraction, decimal
- Percentage =  ___A___  x 100
-                              A + B
- Numerator is always included in the denominator
- Examples:
-  _______# of females in class_______
- 	         # of females + # of males in class
-  ____# of alcohol-related deaths in Sandoval county______
-       Total # of alcohol-related deaths in all 33 NM counties

**Notes:**
Example:  page 6 of State Epi Profile
Proportion implies a numerator (part) and a denominator (whole)

## Calculating Proportions - Example

- Proportion of alcohol-related (A-R) deaths in Sandoval county
- Numerator = # A-R deaths in Sandoval county = 213
- Denominator = # A-R deaths in New Mexico = 5,068
- Time Period = 1999-2003
- Constant = 100

- Proportion of statewide A-R = ___213__  x 100 = 4.2%
- deaths in Sandoval county        5,068

**Notes:**
Example:  page 6 of State Epi Profile
Number of deaths in Sandoval county = 213
Number of deaths in NM = 5,068
Proportion of statewide deaths in Sandoval county:  213/5,068 X 100 = 4.2%
Compare to bar graph on page 7

## Prevalence

- Prevalence = the number of existing cases or events in a certain population at a given point in time
- Prevalence is a proportion and can be expressed as a percentage
- Includes current cases/events
- Must indicate WHEN cases were enumerated
- Prevalence =  _# of existing cases_  = _15__ = 0.10 X 100 or 10%
-                          Total population       150

## Prevalence- ExampleYouth Binge Drinking

- Chart 2: Binge Drinking by Sex and Grade Level, 2003 NM YRRS

**Notes:**
Page 34, Chart 2  
What is the numerator for the first bar:  the number of ninth grade boys who had 5 or more drinks of alcohol in a row in past 30 days 

What is the denominator for the first bar:  the number of ninth grade boys in New Mexico public schools

What is the prevalence of binge drinking among 11th grade boys?  11th grade girls? 

What can you say about the prevalence of binge drinking among children in lower vs. higher grade levels?

Does there appear to be a gender difference?  When?  

## Rates

- Frequency of a defined event in a specified population during a given time period
- Incorporates time into the measure
- Multiplied by a constant for ease of interpretation
- Rate  =  _# events (deaths, cases, etc.)_
-                  ________# people at risk______
-                                      time
- Example:  crude death rate

## Calculating Rates - Example 

- 2002 all cause crude death rate for NM
- Numerator = # of deaths in NM during 2002 = 14,344
- Denominator = total population of NM in 2002 = 1,853,030
- Time Period = 2002
- Constant = 100,000

- Crude death rate = ___14,344___ X 100,000 = 774.1/100,000
-                                 1,853,030

*Source:  CDC Wonder *

**Notes:**
Numerator and denominator match in time period, and in population being described. 

## Age-adjustment of mortality rates

- Death rate – number of deaths occurring in a specified population during a given period of time
- Crude death rate – the death rate in the total population
- Adjusted death rate – recalculation of the death rate using a standard population reference
- Compensates for differences in the age distributions of populations being measured
- Allows comparisons between groups

## Age-adjustment - Example

- Crude death rate (1992-1994)
- Mexico:	  469.6/100,000
- US:  	  869.6/100,000
- Adjusted death rate (1992-1994)
- Mexico:	  596.6/100,000
- US:	  519.1/100,000

**Notes:**
Crude death rate in US appears to be twice that of Mexico
When adjust for age distribution in both countries, the rate in Mexico goes up to 596.6/100,000 and the rate in the US goes down to 519.1/100,000 
Why?  Population in Mexico is younger as a whole than population in US
Death rate in elderly population groups are higher than in US?

## Trends

- Looking at the same data over time
- Data collected the same way over periods of time
- Numbers large enough to calculate percentages or rates for each time period
- Same length of time in each period used as a data point

## Alcohol-Related Motor Vehicle Crash Fatality Rates, New Mexico and US, 1990-2004

*Source:  Division of Government Research, University of New Mexico *

- Alcohol-Related Motor Vehicle Crash Fatality Rates, New Mexico and US, 1990-2004

**Notes:**
What can you say about NM’s alcohol-related motor vehicle crash fatality rates since 1990?  Since 1998?
How do they compare with the US rates?

Alcohol-related motor vehicle crashes are the leading cause of alcohol-related injury death in New Mexico.  Over the past 20 years New Mexico's alcohol-related motor vehicle crash fatality rate has dropped from 1st to 6th among states, in response to a wide range of public health interventions.  New Mexico's alcohol-related motor vehicle crash fatality rate is less than half what it was 20 years ago.  

On the other hand, most of this rate decline occurred during the period 1982-1998.  New Mexico's rate has remained fairly stable since then, running at roughly twice the US rate.  Prevention efforts are currently underway to restart decreases in New Mexico’s alcohol-related motor vehicle crash fatality rate.

## Drug-Related Death Rates* New Mexico and US, 1990-2004

- Drug-Related Death Rates* New Mexico and US, 1990-2004

**Rates are age-adjusted to the 2000 US population*
*Sources: Bureau of Vital Records and Health Statistics, NMDOH; CDC Wonder*

**Notes:**
What can you say about NM’s drug-related death rates since 1990?  What about 2003-2004?
Drug-related deaths are deaths where drugs are a primary cause, such as drug dependence and drug overdose. Unintentional or undetermined drug overdoses are the largest subset of drug-related deaths and account for 70-75% of these deaths in the US. However, this proportion is larger in New Mexico where unintentional drug overdoses account for 79-84% of all deaths due to drugs. National data for 2003 and 2004 are not yet available.

In 2002, New Mexico had the highest death rate from drugs among the states, nearly twice as high as the national rate.  Drug-related death rates in New Mexico have been steadily increasing since 1990 and the peak death rate of 20.0 per 100,000 was seen in 2003.  The death rate decreased in 2004 to 17.3 per 100,000, nearly matching that of 2002.      

Among New Mexico counties, Harding (61.4 per 100,000), Rio Arriba (48.4), Chaves (30.3), De Baca (28.8), Guadalupe (25.2) and Grant (24.7) counties had the highest drug-related death rates for 2002-2004.  The rates for Harding and DeBaca county are highly unstable since they are both based on only 1 death during these 3 years.

* Note that the International Classification of Disease (ICD) codes changed from ICD-9 (prior to 1998) to ICD-10 in 1999 and onwards.  These ICD codes indicate the cause of death.

##  Small Group Exercises

## New Mexico Crude Death Rates By County, 2002

*Source:  CDC Wonder*

**Notes:**
For possible discussion after small group exercises or should I put as example of age-adjustment?

## New Mexico Age-Adjusted Death Rates By County, 2002

*Source:  CDC Wonder*

## Common Sources of Health Data

- Population and demographic data from the US Census Bureau and the Bureau of Business and Economic Research at UNM
- Birth and death data from the NM Bureau of Vital Records and Health Statistics
- Population-based survey data collected by the NM DOH
- YRRS: Youth Risk and Resiliency Survey
- BRFSS: Behavioral Risk Factor Surveillance System
- Hospitalization in-patient discharge data from the NM Health Policy Commission

**Notes:**
Secondary data:  data that already exist 
Data may be collected specifically to represent counts of people and populations, e.g. census data.
Denominator for many rates is census data.
We will talk about death data shortly when we review the NM State Epi Profile.
It is important to realize that the type of data as well as the method of collection will influence the inferences that you can make about a specific population.
Data are also collected to represent utilization of services (encounters, visits).  Administrative data may be used for public health purposes, but they do not represent counts of people and thus have limitations. 
For example, HIDD may be used to count hospital admissions for motor vehicle crash injuries, but this may not be an accurate count of the number of individuals injured in a time period:  an individual could be hospitalized more than once from a single crash incident, or could be involved in multiple crashes within the designated time period
It would be useful information for resource planning, such as for trauma admissions and/or transfers and hospital bed capacity 

## New Mexico SPF-SIG State Epi Profile 

**Notes:**
Secondary data:  example of mortality data
Mandatory reporting of all deaths, including underlying and contributing causes of death, via the death certificate to the State Center for Health Statistics 
Cause-specific death rates can be calculated from these population-based data 

## NM SPF-SIG State Epi Profile

- Provides a systematic and comprehensive overview of ATODA-related consequences ....

**Notes:**
State Epi Profile is useful to program planners designing substance abuse prevention interventions

Mortality data are outcome indicators for alcohol use

## NM SPF-SIG State Epi Profile

- ...  and ATODA-related consumption

**Notes:**
Indicators of substance abuse consumption behavior from self-reported substance use behaviors from statewide surveys

## How to use this report Outcome indicators: consequences

- Problem statement presents overview of the data and detailed statistics
- Outcome indicators – associated with two tables
- Number of deaths on the left side of the table
- Age-specific death rates per 100,000 population on the right side of the table*
- County bar chart showing age-adjusted rates for each NM county in descending order

- *Note: All-ages rate is per 100,000, age-adjusted to the 2000 US population

**Notes:**
Page 5:  Alcohol-Related Death

## How to use this report Outcome indicators – Table 1

- Table 1: deaths and death rates by sex, age group, and race/ethnicity
- Useful in determining the most important risk groups at a statewide level

## How to use this report Outcome indicators – Table 1

- How to use this report Outcome indicators – Table 1

**Notes:**
What is the numerator for alcohol-related deaths among Hispanic females ages 25-64?     233 deaths in this group during the 5 years
What would the denominator be?     187,619(5)=938,095   i.e.  the number of Hispanic females ages 25-64 in the mid-point population, multiplied by 5 years
What would the rate be?     233/938,095 X 100,000=24.8
Note: a combined 5-year period is used when presenting death rates.  Combining deaths over multiple years is necessary because in many of NMs small counties there are very few deaths due to a given cause in any given year.  Allows for calculation of rates that are more stable.

## How to use this report Outcome indicators – Table 2

- Table 2:  deaths and death rates for each NM county by race/ethnicity
- Useful in determining:
- Counties with the most severe substance abuse problems
- Groups with the highest risk within each county

## How to use this report Outcome indicators – Table 2

**All rates are per 100,000, age-adjusted to the 2000 US population*

**Notes:**
What would the numerator be for AR-CLD deaths among American Indians in Cibola county?     35
What would the denominator be?     10,422(5)=52,110

What would the rate be?     35/52,110 X 100,000=67.17   ->   Changes to 84.5 when age-adjusted to the 2000 US population

McKinley county: highest rate of AR-CLD
Within the county, American Indians have an AR-CLD death rate that is 1.7 times the Hispanic death rate

## How to use this report Outcome indicators – County bar charts

- Number of deaths and the percent of NM deaths occurring in each county are given next to the county name on the left side
- Highest death rates are at the top
- State rate shown with a darker bar for comparison

## Example of county 

- Example of county
- bar chart

- Alcohol-Related Chronic Liver Disease Death

-  McKinley county
- AR-CLD death rate:  39.3/100,000
-  McKinley county deaths:  119/1,304 = 9.1% of
- AR-CLD statewide deaths
-  New Mexico
- AR-CLD death rate:
- 14.4/100,000

**All rates are per 100,000, age-adjusted to the 2000 US population*

**Notes:**
**County rates excluded due to small number of deaths (<2 per county per year) during 1999-2003

## How to use this report Rates and numbers

- Example:  McKinley and Bernalillo counties
- Consider both prevalence and rate when designing interventions
- County with highest alcohol-related death rate
- 115.1 deaths / 100,000 population
- County with highest proportion of alcohol-related deaths in the state
- 1,491/ 5,068 = 29.5%

**Notes:**
Alcohol-related death, pages 6 & 7
Which county has highest alcohol-related death rate?
Which county has the highest proportion of alcohol-related deaths in the state?

## Example of county 

- Example of county
- bar chart

- Alcohol-Related Death Rates by County

-  McKinley county
- alcohol-related death rate:  115.1/100,000
-  New Mexico
- alcohol-related death rate:
- 56.7/100,000
-  Bernalillo county 1494/5,068 = 29.5% of
- AR-CLD statewide deaths

**All rates are per 100,000, age-adjusted to the 2000 US population*

**Notes:**
Compare to death rate in Bernalillo:  53.5/100,000
Compare to proportion of statewide deaths in McKinley:  6.9%

## How to use this report ATODA consumption behaviors

- BRFSS data estimate number and percent of people in population engaging in behavior
- Table 1:  Statewide estimates by age, sex, and race/ethnicity
- Table 2:  County estimates by race/ethnicity
- County bar charts arranged in descending order

**Notes:**
Consumption begins on page 29

## Example of county

- bar chart:  BRFSS

- Adult Drinking and Driving Rates by County

-  Luna county:  4.8% of adults reported drinking and driving at least once in past 30 days
-  No estimates available for small counties
-  Bernalillo county accounted for 47.8% of statewide drinking drivers

**Estimate of percent of people in population group who drove after drinking at least once in previous 30 days*

**Notes:**
Page 41
Sample from 5 strata (Regions) so not all counties are well-represented

## How to use this report ATODA consumption behaviors

- YRRS data estimate percent of public high school students engaging in behavior
- Table 1:  Prevalence estimates by grade, sex, and race/ethnicity
- Chart 1:  County bar charts with prevalence estimates  arranged in descending order

## Example of 

- Drinking and Driving Rates by County, Grades 9-12

- Example of
- county bar chart:  YRRS

-  Union county:  35.7% of youth reported drinking and driving in the past 30 days
-   New Mexico:
- 19.1% of youth

**Notes:**
YRRS 2003, Q10:  During the past 30 days, how many times did you drive a car or other vehicle when you had been drinking alcohol?
Not available counties:  ? No county-level estimates available because school districts did not agree to participate in survey or small response reate

## Survey Data

- BRFSS
- Telephone survey of adult health conditions and risk behaviors
- Random sample of adults 18 years of age or older in households with a land-line telephone
- Able to generate population-based estimates for adults
- YRRS
- School-based survey of health risk and resiliency behaviors among 9th-12th graders in NM
- School districts must agree to participate
- Estimates representative of public high school students
- Both surveys include self-reported data

**Notes:**
YRRS:  All public schools in NM are eligible.  Excludes students in private and federal schools (HIS), home-schooled students, and children not in school, i.e. drop-outs
BRFSS:  Adults living in group homes or in institutions (prisons, nursing homes, residential facilities, college dormitories) are not eligible.
Unemployed persons and lower income households are less likely to have telephones and may be underrepresented in the sample.
Both:  Include self-reported health conditions and behaviors
Survey data result from interviewing a small sample of the total population.  It would not be feasible to do a census of every person.  Therefore, each response represents a number of people in the target population and is only an ESTIMATE of the frequency of that characteristic in the true population.  
Confidence Intervals- A measure of the precision of an estimated value.  The interval represents the range of values consistent with the data, that is believed to encompass the “true” value with high probability (usually 95%).  The confidence interval is expressed in the same units as the estimate.  Wide intervals indicate lower precision and narrow intervals, greater precision.
When talking about survey data based on a sample, 
It is important to understand what a confidence interval is because it speaks to the comparability of the data.  Because the data is from a sample of people, we can only say that we are 95% confident that the true response falls somewhere in a range (the confidence interval).  The point estimate is an estimate in the middle of this range

## Adult Drinking and Driving Rates by County

- Alcohol-Related MVC Death Rates by County

**Notes:**
Consequences and consumption data are inconsistent at the state and county level
There may be a number of indicators to look at in order to understand an issue in your community.  For instance, the consumption behavior of binge drinking may also influence the rate of MVC deaths, but other factors may also be contributing to the problem:  alcohol outlet density, low pricing, etc. 

## How to use this report Missing data

- Rates calculated using small numbers are unstable and difficult to interpret
- Exclusions of rates occurred if:
- Fewer than four deaths and population <20 in the rate denominator (NM standard small numbers rule)
- Fewer than two deaths per county per year
- Results in data gaps for certain groups

**Notes:**
Rates and measures based on small or unstable numbers should be interpreted cautiously. For example, if three out of nine participants in a workshop smoked cigarettes, claiming a smoker rate of 33% could be a bit misleading. Remember, it’s only three people. That rate is “unstable.” It would change considerably if one person quit smoking or if one non-smoker joined the group. However, some counties have such a small population, you might not be able to avoid small numbers. In that case it might be possible to use multiple years of data to determine some rates.

## NM standard small numbers rule

- Examples of cells affected  by additional SPF-SIG rule

## Data Collection

- Think about data availability as a pyramid
-  Numerator – what are you counting?
-  Denominator – who is in the target population?
-  Are the data already available?
-  If not, can they be collected in a systematic way?

**Notes:**
Primary data:  data that have not been collected
Looking at mortality data gives us a small view of the extent of the problem in the population.  It is an indicator or bit of measurable information that tells us about the health status of a population.  HIDD data reflect the most severe cases of disease.  Rates of hospitalization for a disease do not represent the prevalence of disease in a population.  In addition, hospitalization data counts discharges, not people unless unduplicated data of persons hospitalized are analyzed.  
Many more individuals with a health condition will have an encounter with the health care system as an out-patient, and still more may never be recognized as having a condition:  no use or access to care, undiagnosed condition, etc.

## Data Collection

- Numerator:  Counting DWI convictions in 2004
- Denominator:  Determining the population at risk

- Example 1 – 2004 DWI Conviction Rate for New Mexico

**Notes:**
Data exists, but you may want to define it in a different way

Numerator:  
Persons cited for DWI in 2004
Persons convicted of DWI in 2004

Where is this information available?  Motor Vehicle Division DWI citation tracking system (DWICTS) ? and County Client Tracking Program

Denominator:  
Population at risk of arrest for DWI or already cited for DWI, but without a conviction yet
Is total population at risk of arrest for DWI all the people driving through NM (from neighboring states, Mexico, tourists), residing in NM, licensed and/or unlicensed drivers, etc.

Note: DWI convictions are those handed down in 2004.  Citations that resulted in these convictions could have been issued prior to 2004.  Convictions are counted by county of driver residence, not the county in which the citation was issued.  Driver residence county was determined by zip code.  The 805 convictions received by drivers with missing, invalid, or out-of-state zip copes (Other) are included in the total convictions.

## Example 1 

- 2004 DWI Conviction Rate for NM
- Numerator = # of DWI convictions in NM in 2004 =12,639
- Denominator = # of licensed drivers in NM in 2004 =1,289,089
- Time Period = 2004
- Constant = 1,000

- DWI Conviction Rate NM 2004 =  __12,639__ X 1,000
-                                                       1,289,089
- 			                =   9.80/1,000

*Source: New Mexico Department of Transportation, Driving While Impaired in NM, 2004 Report*

**Notes:**
The denominator includes only those at risk of being in the numerator.  
What does this measure?  Is is population that drinks and drives or measure of law enforcement measure

## Data Collection

- Numerator:  Counting FAS cases in NM
- Denominator:  Determining the population at risk

- Example 2 – Fetal Alcohol Syndrome (FAS) Rate in New Mexico

**Notes:**
Numerator:  Fetal alcohol syndrome results from maternal alcohol use during pregnancy.  Despite the known adverse effects of this exposure, children who experience them often do not receive a correct diagnosis or referral for diagnostic evaluation because of absence of uniformly accepted diagnostic criteria and referral guidelines.  
Represents a continuum of effects: fetal alcohol effects, alcohol-related birth defects, alcohol-related neurodevelopmental disorder, fetal alcohol spectrum disorders.
Present at birth, but may go unrecognized for years

Denominator:  Women who drink during pregnancy.  How do we measure this?  
Consumption of alcohol during pregnancy is collected on birth certificate, but much data are missing and consumption amounts are underreported
PRAMS collects this data as well from a sample of mothers who delivered in past 6 months

## Diagnosis of FAS

- Documentation of 3 dysmorphic facial features
- Prenatal or postnatal growth deficit in height or weight
- CNS abnormality
- Diagnosis classified on the basis of available history of confirmed or unknown prenatal alcohol exposure

**Notes:**
3 dysmorphic facial features:  Smooth philtrum, thin vermillon border, and small palbebral fissures
CNS abnormality may be structural, neurologic, or functional.

## Mothers Who Drank Alcohol Three Months Prior to Pregnancy and During the Last Three Months of PregnancyNew Mexico, 1998-2002

*Source: Pregnancy Risk Assessment & Monitoring System (PRAMS), NMDOH*

**Notes:**
18.6% of pregnant women drank 7 or more drinks per week or more than 4 drinks in one sitting (NM PRAMS 1998-2002) in the 3 months before their pregnancy
In addition, approximately half of all US pregnancies are unintended

Prenatal exposure to alcohol is among the most commonly identifiable causes of mental retardation and neurodevelopmental disorders, and is associated with miscarriages, birth defects and growth disorders. There is no known safe level of prenatal alcohol consumption or safe time during pregnancy to drink.  In 2005, the U.S. Surgeon General warned women who are pregnant or may become pregnant to abstain from alcohol consumption.

In 2002, 45.9% of mothers drank during the three months before pregnancy and 4.4% of mothers drank during the last 3 months of pregnancy. These rates have remained relatively stable since 1998.

In 2000, the prevalence of fetal alcohol syndrome (FAS) in New Mexico was similar to the national rate of 1.1 per 1,000 births.  Each year in New Mexico approximately 30 children are born with FAS and more than 250 are born with Fetal Alcohol Spectrum Disorders.

## Example 2

- FAS Prevalence Rate in NM
- Numerator = # FAS-affected children born 1998-2002
- Denominator = # live births in NM 1998-2002
- Time Period = 1998-2002
- Constant = 10,000

**Notes:**
From Georgia, Metropolitan Atlanta Congenital Defects Program 1998-2002
Fetus or newborn affected by maternal alcohol use:  1.48 per 10,000 live births
From CASAA:  Center on Alcoholism, Substance Abuse, and Addictions, Statewide FAS Prevention Program at UNM
In 2000, the prevalence of fetal alcohol syndrome (FAS) in New Mexico was similar to the national rate of 1.1 per 1,000 births.  Each year in New Mexico approximately 30 children are born with FAS and more than 250 are born with Fetal Alcohol Spectrum Disorders.

Worldwide: various prevalences of 0.2-1.5 cases per 1,000 live births

## Data Collection - Discussion

- What are some other substance use consequences in your community?
- Are there data already available?
- If data need to be collected, how would you define a case/event (numerator) and the population at risk (denominator)?
- Who can you call for help?

## Acknowledgments

- Dan Green, Social Indicator Epidemiologist
- Jim Roeber, Alcohol Epidemiologist
- Substance Abuse Epidemiology Unit
- Corazon Halasan, Community Epidemiologist
- Community Health Assessment Program

## Contact Information

- Tierney Murphy
- Substance Abuse Prevention Epidemiologist
- New Mexico Department of Health
- Phone:  827-6816
- E-mail:  tierney.murphy@state.nm.us

## Omitted Slides

## Data Collection

- Example 3 – School Truancy Rate in Your
- Community

- Numerator:  Counting middle and high school students who have unexcused absences
- Denominator:  Determining the population at risk

## Binge Drinking* Among Currently Drinking Adults by Age, New Mexico 1998-2004

** **5 or more drinks on one occasion*
*Source: New Mexico BRFSS, Injury and Behavioral Epidemiology Unit, NMDOH *

**Notes:**
Age is an important factor to consider in relation to binge drinking.  Among current drinkers, young adults (age 18-34) are significantly more likely to binge drink than middle-aged (age 35-54) or older adults (age 55+).  Middle aged adults are significantly more likely to binge drink than older adults (age 55+). 

There are no significant differences in the prevalence of binge drinking between young adult subgroups (i.e., 18-20 versus 21-25 versus 26-34 year olds).  The significantly higher rate of binge drinking among young adults persists well into adulthood.  This risk behavior is not restricted to younger (e.g., college-age) adults. 

In order to decrease binge drinking and related adverse health outcomes, age-specific strategies are indicated.

## Adult Binge Drinking by County

- Alcohol-Related MVC Death Rates by County

**Notes:**
Consequences and consumption data are inconsistent at the state and county level

## Calculating Rates

- Numerator:  Counting liquor outlets in 2002
- Denominator:  Determining the population at risk

- Example 2 – 2002 liquor license density rate for Rio Arriba county

## Calculating Rates – Example 3

- Liquor License Density
- Numerator = # licensed facilities in Rio Arriba county
- Denominator = 2002 population of Rio Arriba county aged 20 years and older
- Time Period = 2002
- Constant = 1,000

- Liquor License Density Rate Rio Arriba County 2004 = 2.7

*Source: New Mexico Alcohol and Gaming Division, Regulation and Licensing Department*

## Incidence Rate (Risk)

- Incidence = the number of NEW cases/events in a population over a given period of time
- Measures the probability of an event/case occurring during a period of time
- IR = _Number of NEW events during time period_
-    Total population at risk for event

**Notes:**
? omit

## Alcohol-Related* Death RatesNew Mexico and US, 1990-2004

*Sources: Bureau of Vital Records and Health Statistics, NMDOH; CDC Wonder*
*Rates are age-adjusted to the 2000 US Standard Population*

- Alcohol-Related* Death RatesNew Mexico and US, 1990-2004

**Notes:**
For the past twenty-five years (fifteen of which are shown above), New Mexico’s alcohol-related death rate has been more than twice the national rate, and second among states for most years, after Alaska.  National data for 2003 and 2004 are not yet available.

For 2002-2004. the highest alcohol-related death rates among New Mexico counties were for McKinley (50.2 per 100,000), Cibola (45.4), Mora (42.3), Rio Arriba (39.3), and Catron (38.0) counties.  The 2002-2004 rate in McKinley County was 7.4 times the 2002 U.S. rate.

## NM’s standard small numbers rule

- Examples of cells affected  by additional SPF-SIG rule

**Notes:**
How does a zero numerator give any rate?

## Slide 58

## Data Collection – General Principles

- Numerator – what are you counting
- Denominator – who is in the target population
- Is the data already available?
- If not, can it be collected in a systematic way?

**Notes:**
Primary data: data that haven’t been collected

Useful when:  you need opinions from your community
You need information on resources and assets
You need information specific to your community or a certain age group
You need an assessment of local laws and policies

How to collect it:  focus groups, key informant interviews, surveys, asset mapping (participatory planning and action tools)