Look at sample sizes and survey response rates - representative of your population? Enough responses to be valid?
Who was surveyed? - representative of population being compared to? Include group you are interested in?
Were the survey respondants from heterogeneous groups? Do the survey questions have a similar meaning to members of different groups?
How was survey conducted? Via telephone? - Many people only have cell phones. Random selection or targeted group?
What assumptions and methods were used for extrapolating the data?
Look at definitions of characteristics - Does this match your own definitions?
Who identified race/ethnicity of respondents/participants?
When was the data collected?
Reliability and validity:
Reliable data collection: relatively free from "measurement error."
Is the survey written at a reading level too high for the people completing it?
If I measure something today, then measure it again tomorrow using the same scale, will it vary? Why?
Validity refers to how well a measure assesses what it claims to measure
If the survey is supposed to measure "quality of life," how is that concept defined? Is it measurable?
Extensive discussions of reliability and validity are available in several texts, such as Textbook in Psychiatric Epidemiology (3rd Ed.; M. Tsuang et al. Wiley. 2011; See chapters 5 and 7).
Quickly get recent state, county, and city demographics, including age, race/ethnicity, income/employment, residence, education, languages spoken, and more.
Access data and digital content from the U.S. Census Bureau. Data sets from the census and the economic census are available and custom tables and maps can be created from the data. This platform replaces American FactFinder.
US CDC
National Vital Statistics System:
Births | Deaths Compilation of US birth and death certificate data
The world's largest, on-going telephone health survey system, tracking health conditions and risk behaviors in the U.S. yearly since 1984. Prevelance Trends, GIS data, Chronic Disease Indicators, as well as the survey data and methodology are available.
BRFSS state and MMSA information on numerous topics/categories: alcohol, physical activity, screening, injury, tobacco, fruit & vegetable consumption, and more.
Information on youth risk behaviors. Topics include:
- Unintentional injuries & violence
- Tobacco use
- Alcohol & other drug use
- Sexual behaviors
- Dietary behaviors
- Physical activity
- Asthma
Provides access to a variety of CDC reports, guidelines, and databases. Includes census data, mortality data, and natality data, as well as surveillance information.
Provides data on the number and rates of injury and illnesses by industry, details on the injured worker, nature of the disabling condition, and the event resulting in the disabling condition, and details on fatal incidents.
Examines and monitors more than 100 indicators that focus on risks and positive developments for children. For each indicator they summarize what the research says about its importance to children’s development, track trends over time and by subgroup, and highlight strategies likely to improve well-being.
The largest state health survey in the United States. It is a telephone survey conducted every two years on public health topics and access to health care. The web site contains the questionnaires, data files, and AskCHIS, an online data query system. (Requires one-time, free registration).
Offers access to standardized, non-confidential health and human services data that can be combined, downloaded, sorted, searched, analyzed, redistributed and re-used by individuals, business, researchers, journalists, developers, and government to process, trend, and innovate.
Links to every individual California county web site. May be useful for finding county level information.
Local public health departments are often a good source of community statistics and other information.
Tracks the well-being of children in the United States. Data is provided nationally and state-by-state. You can generate custom graphs, maps, ranked lists, and state-by-state profiles. Also, download the entire Kids Count data set as delimited text files. Indicators include: Infant mortality & child deaths, juvenile arrests, low birth weight, immunizations, children in poverty, education, and more.
This scorecard provides county-level data visualizations, tracking 28 key indicators of child well-being across all California counties, over time and by race and ethnicity. Additionally, for each indicator, the relative performances of counties are grouped by county population density and percentage of children living above poverty.
The Map Room provides > 15,000 data layers down to census tract level for demographics, social and economic factors, physical environment, health behaviors, clinical care, and health outcomes, as well as a Community Health Needs Assessment reporting tool with 80+ health-related indicators. From the Center for Applied Research and Engagement Systems (CARES) at the University of Missouri.
Includes vital health factors, including high school graduation rates, obesity, smoking, unemployment, access to healthy foods, the quality of air and water, income, and teen births in nearly every county in America. National & state data download: csv (national also SAS).
Map and list hazardous waste cleanup locations and grant areas, and drill down to details about those cleanups and grants and other, related information.
Data on school enrollment, non-English language learners, free lunch numbers, teacher and staff data, class size, revenue sources and amounts, and much more. Includes access to Ed-Data: timely and comprehensive data about K–12 education in California.
Has data available for viewing and downloading such as Hospital Annual Financial Data, Hospital Quarterly Financial Data, Utilization Data, Long-term Care Facility Financial Data, Patient Discharge Data, etc. Formerly known as OSHPD.
Provides access to an interactive repository of health statistics. Users are able to display data for selected indicators, health topics, countries and regions, and download the customized tables in Excel format.
Allows users to make custom tables based on thousands of demographic and health indicators across more than 90 countries. Customize tables to view indicators by background characteristics, over time, and across countries. STATcompiler allows users to visualize and explore these data in column charts, line graphs, maps, and scatterplots.
Access to thousands of indicators with time series for 246 countries/country groups from 1960 to present. Data includes vital statistics, demographics, labor force, health expenditures, malnutrition, gender, nutrition, pollution, trade, consumption, GDP/GNP, investment activity, debt, and much more.
A statistics portal that integrates data from reliable sources on thousands of topics
Categorized into market sectors, Statista provides access to quantitative facts on media, business, politics, and other areas. Sources of information include market research reports, trade publications, scientific journals, and government sources. Data may be downloaded into spreadsheets and presentations. Also includes industry reports.
Additional Resources: The Library's Guide to Health Statistics & Data
