This data biography includes information about who created this data, and how, where, when, and why it was collected. We (the Assessment, Policy Development, and Evaluation Unit at Public Health – Seattle & King County) created it to help you understand where the data comes from and its strengths and limitations. If you have any further questions, please don’t hesitate to reach out to us at data.request@kingcounty.gov!

Who collects the data? 

Hospitals in Washington State collect inpatient and observation data on patients admitted into hospitals and submit it to the Washington State Department of Health using the Comprehensive Hospital Abstract Reporting System (CHARS), which the Washington State Department of Health oversees. Inpatient refers to patients who are admitted to a hospital for at least one night, while observation refers to those admitted for a shorter period of time. CHARS is a system used to collect and track data to identify and analyze hospitalization trends. 

Who owns the data? 

The Washington State Department of Health’s Center for Health Statistics owns the data. A limited, de-identified (i.e. anonymous) dataset is freely available for public use. However, a data sharing agreement and fee are required to access record-level data stored in CHARS. The Department of Health maintains confidentiality of the data stored in CHARS and creates system safeguards to prevent any unauthorized access and modification to the data. 

How is the data collected?  

Data is collected by hospitals, who consolidate the data and securely submit it into CHARS. Data collection processes vary among hospitals, but generally when a patient visits a hospital, their clinicians record information about their demographics, diagnosis and treatment in the electronic health record system the hospital uses. Hospitals must inform patients that providing their information is voluntary. Based on the process the hospital adopts, the data is processed to conform to CHARS’ operating structure. CHARS performs data quality checks on data submitted by hospitals and returns potential errors to hospitals to fix.     

Who is included and excluded from the data?  

All inpatient and observation patients admitted to Washington Hospitals are included in CHARS. People who do not seek healthcare at hospitals, whether because they do not need it or because they experience barriers such as cost or stigma, are not included in CHARS.  

Where is the data collected? 

Data is collected independently by each hospital in Washington State. There is not one streamlined process that each hospital uses to collect medical data. Instead, hospitals adopt unique processes that meet their needs, priorities, and functionalities. Ultimately, after patient visits and discharge data are collected, this data is then prepared and submitted into CHARS.   

Why is the data collected? 

This data is collected to identify hospitalization trends and analyze health care access, quality, and cost.  

How often is this data collected? 

Data is collected by hospitals on an ongoing basis. The CHARS system stores up to 12 months of data online so that corrections and adjustments can be made by hospitals. The system stores the previous years’ final data for analysis and reporting. Annual CHARS inpatient data is available from 1987 forward, and observation data is available starting in 2009. 

What else is important to know about this data?  

Public Health – Seattle & King County uses CHARS data as a public health surveillance tool. For example, CHARS has been used to analyze hospitalization rates by conditions and demographics.  

Hospitals submit separate discharge records for mother and baby. All babies born in a hospital are reported as a discharge in CHARS, even if the baby stays less than 24 hours. 

Due to a transition in classification of diagnosis and procedure codes, CHARS data from before October 2015 cannot be compared to data from after that date. 

Where can I learn more about this data?  

• Washington State Department of Health: Comprehensive Hospital Abstract Reporting System (CHARS) 

• King County CHARS Data Dashboard 

About data privacy and security 

The Assessment, Policy Development, and Evaluation Unit takes data security and the privacy of all individuals represented in our data very seriously. Data are stored in a secure environment.  For data sets that are not publicly available, only authorized staff are able to access them. Each data set has privacy guidelines to prevent sharing any information that may be identifiable – for example, not sharing (sometimes called suppressing) numbers when they are very small.