The patient record file
Every patient record that met the inclusion criteria was identified, and the record book drawn using the hospital information system. The patient record file that fulfilled every third patient admission number was drawn until the sample was obtained. The sample size was calculated using a 95% Confidence Interval, and 80 samples were taken for analysis. The fluid balance was calculated using 6% precision, 95% CI width, and 10% error rate. A sample of N=103 was taken and divided among the various units under the guidance of the statistics table. Descriptive statistics were recorded coupled with the conduction of the Mann-Whitney U-test to check the associations subsisting the recorded variables with the fluid balance calculation accuracy.