FAQ - Dataset and Health Indicators

7/30/2012

DATASETS and HEALTH INDICATORS

What data sets are contained in IQuery?

IQuery launched in 2011 with data from the Illinois Department of Public Health: Vital Statistics, the Adverse Pregnancy Outcomes Reporting System (APORS), and census information for Illinois. Since then, several other departments have placed their data in IQuery, including Hospital Discharge, STDs, and Communicable Diseases. Other data sets are still in development and will be added as their agency and/or departments publish their data in the system.

What are age-adjusted rates?

The rates of almost all causes of disease, injury, and death vary by age. Age adjustment is a technique for "removing" the effects of age from crude rates so as to allow meaningful comparisons across populations with different underlying age structures. For example, comparing the crude rate of heart disease in Florida with that of Illinois is misleading, because the relatively older population in Florida leads to a higher crude death rate, even if the age-specific rates of heart disease in Florida and Illinois were the same. For such a comparison, age-adjusted rates are preferable.

What are crude rates and how are they calculated?

A rate is a measure of some event, disease, or condition in reference to a population. Crude rates are calculated by dividing the number of events or cases by the population.

Why do some health indicators have more description details than others?

IQuery presents data as collected and released by different state agencies. The data collected, stored and displayed varies widely because of different laws and mandates for data collection, different collection methodologies, and different anticipated uses. Data descriptions are provided by the offices and mangers responsible for that data. Please contact those data managers for more information about the data itself.

How do I find the citation and/or contact information for IQuery data?

Each IQuery indicator is followed by a to access more details, also known as metadata. These details may include such information as descriptions, data sources, contact information, timeframe, etc. A shortened version of these details is presented alongside the tabular and graphic results.

How current is the data being displayed?

Datasets for a specific period are provided by individual Data Managers. Based on the timeliness of when the data is presented to them and they can in turn load into IQuery will determine how quickly it is available. As you select a Health Indicator in IQuery, the years for which data has been reported will be available for your selection.

Why are the data in IQuery two years old or older?

Public health data are collected, tested, analyzed and released following a complex process designed to ensure their accuracy, clarity and internal consistency. Data are released to the public only after required approvals have been obtained.

When will new data be available?

Datasets for a specific period are provided by individual Data Managers. Based on the timeliness of when the data is presented to them and they can in turn load into IQuery will determine how quickly it is available.

Can I be notified when new data has been published (or unpublished)?

The ability to be notified when a dataset has changed is an enhancement that the IQuery team recognizes as valuable and is considering. Until that functionality is included in IQuery, you may sign up for general updates on the Feedback page, and you will received information about all new datasets, indicators and updates.

Why are some data presented in three- or five-year ranges?

Multiple-year ranges ensure the privacy/confidentiality of the data by allowing reported instances of an indicator are not too small to publically report.

Why do the tabular and graphical results sometime omit crude or age-adjusted rates?

IQuery automatically calculates rates if the necessary data to do the calculations is present. Crude rates are possible if the number of cases and events is known relative to the population, but the cases must be known for a given population. For example, IQuery may include the number of "Deaths caused by Diabetes" for the city of Douglas, but without knowing the population of Douglas, the crude rate cannot be calculated.

Age-adjusted rates require additional data about how the event or conditions are distributed across the population by age. Without that age range information, age-adjusted rates cannot be calculated, and therefore not presented. Extending the example above, IQuery is programmed with the number of cases of different cancers from 1987 to 2007. However, IQuery currently has population age distributions for 2000 and forward, so age-adjusted rates cannot be calculated for the years before 2000.

When selecting a "Health Indicator," why do I get different choices for "Geographic Area" (or "Time Period" or "Population Demographics")?

This is a result of two design priorities within IQuery. In the first case, IQuery is designed to return results with as much detail as possible. For example, if "Death by Accident" is available for all counties in Illinois, then IQuery will present that. If other data is only available by a total for the whole state, then that is all that can be presented.

Secondly, IQuery is designed to reflect your choices as you move through the data query. Extending the example above, if you select a health indicator that is only available at the county level, then you will only get counties under Geographic Area. Furthermore, only counties that have relevant data for your search will be displayed under the Geographic Area tab get counties on your list that have results for your Health Indicator choice.

Why isn't a particular county or region displayed in the Geographic Area selection?

IQuery has intelligent processing built in so that only Geographic Areas for which data is available for the selected Health Indicator will appear. If a particular county does not appear, it means that no reported cases exist in that county, the data is not currently available, or that type of data is not collected on a regional basis.

Why isn't there an option to display data by a larger aggregation like region, or a smaller area like township?

Datasets are provided by individual Data Managers. In general, they publish the information in geographic areas that are available to them. However, if you have specific questions, please contact the appropriate Data Manager.

Why isn't a particular year or year grouping displayed in the Time Period selection?

IQuery has intelligent processing built in so that only Time Periods for which data is available for the selected Health Indicator and Geographic Area will appear. If a particular Time Period does not appear, it either means that no reported cases exist during that Time Period, or the data is not currently available.

Why isn't a particular race, ethnicity, gender or age group displayed in the Population Demographics selection?

IQuery has intelligent processing built in so that only Population Demographics for which data is available for the selected Health Indicator, Geographic Area, and Time Period will appear. If a particular race, ethnicity, gender or age group does not show as a selection, it means that data for that demographic does not exist or is not available.