[Evaluation of a medical records archive through the application of statistical methods for quality control]

In undertaking a Minimum Basic Data Set (MBDS) of hospital discharges has to be done for all hospitals. It depends on the good function of the Medical Records Archive. The objective of this study is the continuous evaluation of the quality of the Medical Records Archive via Control Diagrams statistical techniques arose.

From June 2005 to January 2009 a retrospective search of the discharges/Medical Records pending coding, from a tertiary care university hospital was carried out. The different categories of discharges/Medical Records were registered on an Excel spreadsheet under the following headings: searched for, found, completed/closed, pending and not located for each a particular month and year. The Overall Effectiveness Index was calculated, 0,9 being the standard quality value. Furthermore to assess the process quality over the entire length of the period studied and in each month and year, the Shewhart's Control Diagram and Cumulative Sum (CUSUM) graphic tests were applied.

The Overall Effectiveness Index was 0.95. The majority of % errors corresponded to November 2008 with 55 (11.73%) and June 2008 with 14 (10.45%). In the Control Diagrams there are abnormally high values, obtained after standardization, in July 2005 (5.95) and November 2008 (7.00). The CUSUM showed one point outside of the initial control (July 2005 - 5.95), although until June 2007, the average (4.7%) was slightly below the overall averages (4.81%) and then increases from July 2007 on (5.02%).

The Archive quality has varied over time, demonstrating that it was especially lower at the end of the study.