Frequently Asked Questions

General

Why was the County-level Study (CLS) conducted?
How and when were 2011 CLS data collected?
Who participated in the 2011 CLS?
What kinds of questions were on the 2011 CLS?
Who paid for this study? Were state dollars used?
How can I obtain the complete study results?
How will the information be used?
These data are from adults. Do we have similar data for youth?
Are there other states that have conducted a large county survey like this one?

Study Design and Methodology

Why were sample sizes of 400 for smaller counties and 800 for larger counties used?
Why aren’t demographic breakdowns (age, race, income, education, health insurance status) provided for counties?
Why and how are data weighted?
What are the study limitations?
Which should be reported, age-adjusted or weighted prevalences?

General

Why was the County-level Study (CLS) conducted?

The need was identified for county-specific prevalence of tobacco use and related chronic disease risk factors, conditions and preventive practices to assist counties with determining health priorities and evaluating programmatic efforts.

How and when were 2011 CLS data collected?

CLS data were collected through random-digit-dialed (RDD) landline telephone interviews and random manually dialed cell telephone interviews conducted by trained interviewers at the University of Missouri-Columbia Health and Behavioral Risk Research Center. Data were collected January through December, 2011.

Who participated in the 2011 CLS?

What kinds of questions were on the 2011 CLS?

Who paid for this study? Were state dollars used?

The Missouri Foundation for Health paid for the entire study.  No state funds were used.

How can I obtain the complete study results?

Study results are available on the DHSS Community Profiles web site.  Researchers wishing to obtain the complete data set should contact the DHSS CLS Coordinator at 573/526-6660.

How will the information be used?

It is expected that local health departments, organizations and coalitions will utilize the data for determining priority health needs and planning interventions to address priority needs. If the study is replicated in the next few years, data could be used as part of an evaluation of programmatic efforts.

These data are from adults. Do we have similar data for youth?

There are no similar county-specific data available for youth (under age 18). The Youth Tobacco Survey (YTS) administered by the DHSS provides some similar data at the state level only.

Are there other states that have conducted a large county survey like this one?

Few states have conducted a county-level study of this size. California conducts a large health survey, and Florida and Illinois have also conducted large county surveys.

Study Design and Methodology

Why were sample sizes of 400 for smaller counties and 800 for larger counties used?

The sample sizes were selected to obtain acceptable margin of errors for the prevalence estimates at an affordable cost.  An 800-sample size was used in Jackson and St. Louis counties and the City of St. Louis to obtain prevalence estimates for both African American and whites.

Why aren’t demographic breakdowns (age, race, income, education, health insurance status) provided for counties?

A sample size of 400 respondents in most counties does not provide a sufficient number of responses to stratify by demographics at the county-level. Stratification was completed for race in Jackson and St. Louis Counties and the Cities of St. Louis  where oversampling was done to obtain 400 completed interviews each with white and African American respondents, and in Kansas City because of the oversampling in Jackson County .   

Why and how are data weighted?

Weighting allows results to be generalized to the adult population at the state, region and county levels.
Data were weighted to adjust for the unequal probability of selection, differential nonresponse, and possible deficiencies in the sampling frame. For more details on the weighting methodology, go to http://health.mo.gov/data/brfss/BRFSSweightingmethod.pdf.

What are the study limitations?

Respondents were non-institutionalized adults thereby excluding adults residing in nursing homes, mental institutions, and correctional facilities from the study. Data are self-reported and thereby subject to recall bias. Additionally, adults living in residences without a landline telephone that do not use a cell telephone or that do not speak English are not represented in the study.

Which should be reported, age-adjusted or weighted prevalences?

Prevalence is the proportion of a population that has a disease, condition, or risk factor at a particular point in time or over a specified period of time. It is a measure of the burden of diseases, conditions, and risk factors, while age-adjusted prevalence is a hypothetical number, which adjusts the prevalence based on the age distribution of another population (e.g., the 2000 U.S. Standard Population). When describing the burden of diseases, conditions and risk factors for the state, a region or a county, the prevalence should be used. When comparing the burden of disease among counties or regions, the prevalence should be reviewed first. If age is a risk factor for the disease and the age distributions are different among counties and regions, then look at the age-adjusted prevalence to determine if the difference or lack of difference in prevalence estimates is due to age.