Assessing the quality of clinical data in a computer-based record for calculating the Pneumonia Severity Index

Objective: This study examined whether clinical data routinely available in a computerized patient record (CPR) can be used to drive a complex guideli ne that supports physicians in real time and at the point of care in assess ing the risk of mortality for patients with community-acquired pneumonia. Setting: Emergency department of a tertiary-care hospital. Design: Retrospective analysis with medical chart review. Patients: All 241 inpatients during a 17-month period (Jun 1995 to Nov 1996) who presented t o the emergency department and had a primary discharge diagnosis of communi ty-acquired pneumonia. Methods/Main Outcome Measures: The 20 guideline variables were extracted fr am the CPR (HELP System) and the paper chart. The risk score and the risk c lass of the Pneumonia Severity Index were computed using data from the CPR alone and from a reference standard of all data available in the paper char t and the CPR at the time of the emergency department encounters. Availabil ity and concordance were quantified to determine data quality. The type and cause of errors were analyzed depending on the source and format of the cl inical variables. Results: Of the 20 guideline variables, 12 variables were required to be pr esent for every computer-charted emergency department patient, seven variab les were required for selected patients only, and one variable was not typi cally available in the HELP System during a patient's encounter. The risk c lass was identical for 86.7 percent of the patients. The majority of patien ts with different risk classes were assigned too low a risk class. The risk scores were identical for 72.1 percent of the patients. The average availa bility was 0.99 for the data elements that were required to be present and 0.79 for the data elements that were not required to be present. The averag e concordance was 0.98 when all a patient's variables were taken into accou nt. The cause of error was attributed to the nurse charting in 77 percent o f the cases and. to the computerized evaluation in 23 percent. The type of error originated from the free-text fields in 64 percent, from coded fields in 21 percent, from vital signs in 14 percent and from laboratory results in 1 percent. Conclusion: From a clinical perspective, the current level of data quality in the HELP System supports the automation and the prospective evaluation o f the Pneumonia Severity Index as a computerized decision support tool.