|  CKD resources page  |  Clinical Informatics  | Clinical Informatics
University of Surrey
Email: info@clininf.eu

eGFR calculator instruction manuals : Excel spreadsheet for multiple calculations

This Excel spreadsheet is capable on multiple calculations of eGFR. I.e. for a list of patients. The patient identifiers (name/NHS number etc), Creatinine values, age, ethnicity and gender can be pasted directly to the spreadsheet. The application calculates the eGFR value for the each patient and their CKD stage is displayed for each raw of data. If any invalid values are found in the data rows, the relevant cells are flagged up and the appropriate error message is displayed. The cells which display the CKD stage are colour coded according to its severity. The entire list can be sorted based on the CKD stage to have the patients with stage 3-5 to be displayed in the top of the list ordered according to their severity.

1.0 Installation requirements

2.0 Instructions for installation

3.0 Instructions for use

1.0 Installation requirements

  1. Live internet connection to download the spreadsheet version of the eGFR Desktop calculator (File size 92 KB)
    the pre-downloaded calculator can also be transferred to the destination computer using a physical media (e.g. Floppy diskette, Flash Drive) or using an electronic media (e.g. as an attachment to an email).
  2. A Desktop or Laptop PC running Windows 98, WinMe, 2000, or XP. The desktop version of the eGFR calculator runs as a off-line standalone application; therefore no internet connection is required.
  3. Microsoft Excel application of the Microsoft Office package.

2.0 Instruction for Installation

  1. Visit the 'CKD resources' web page of the Clinical Informatics Website (www.clininf.eu/ckd). This has a list of all the calculators designed to calculate the eGFR listed under the 'Calculators' heading.
  2. Click on the 'Excel eGFR calculator' link. This will give a file download dialog box (Figure 1). Click on 'Save' button and select an appropriate location to save the eGFR calculator (e.g. Desktop, My Documents etc).

    Figure 1
  3. The eGFR spreadsheet will start to download and message box shown in figure 2 will appear informing the completion of the download. Press the 'Close' button and close the message box.

  4. Figure 2

  5. The eGFR spreadsheet calculator's icon with the name 'gfr.xls' will appear in the location where you selected to save the application in step 3 (Figure 3).

  6. Figure 3


3.0 Instructions for use

  1. Execute the eGFR spreadsheet by double clicking on the icon shown in figure 3. This will launch the eGFR spreadsheet as shown in figure 4. If a security warning message appears as shown in figure 5, follow the instructions in step 4.1. Otherwise go directly to step 2.

    Figure 4
  2. The eGFR spreadsheet application is developed using the Macro programming facility which is embedded into Microsoft Excel. When the spreadsheet is launched or when the calculate button of the spreadsheet is pressed a security warning as shown in figure 5 might appear. This is due to the security settings of the Excel application. The Macro feature should be enabled to use the eGFR.

    Figure 5
  3. Macros can be enabled in two methods. Click on the 'Enable Macro' button on the message shown in the figure 5. Or go to 'Tools' section from the main menu of the excel sheet and select 'Security' section (Figure 6), then set the security level to 'Medium' (Figure 7). To examine whether you have successfully enabled Macros, try clicking on the 'calculate' button without entering any data. If it is enabled it should not give any error/warning messages.

  4. Figure 6

    Figure 7

  5. Generate list of patient names; Serum Creatinine value (umol/l – UK standard units); Age (in years); gender (M/F).
  6. Paste the list of patient names into the ‘Patient name’ column.
  7. Paste the list of serum Creatinine values (umol/l – UK standard units) into the ‘Serum Creatinine value’ column taking care that the serum Creatinine value aligns with the corresponding patient name. The valid range for the
  8. serum Creatinine is 30 – 1500 umol/l.
  9. Paste the list of patient ages (years) into the ‘Patient age’ column taking care that their ages align correctly to the corresponding patient. Age values should fall within the valid range of 18 – 110 years.
  10. Paste the list of patients’ gender (M/F) into the ‘Patient gender’ column, again take care that all the rows of data align correctly. Gender values should be either M (male) or F (female). This cell is not case sensitive.
  11. Please type the letter ‘B’ in the ‘Ethnic origin’ column if the patient is known to be of ‘Black ethnic origin’. Any other ethnicity should be represented by the letter 'O'. If this value is left blank or any other value other than the letter ‘B’ or ‘O’ is used here, the calculator will mark these cells as having invalid values. This cell is not case sensitive.

  12. Figure 8

  13. Once the necessary data is entered to the spreadsheet, press the 'Calculate' button. This will calculate the eGFR values for the list pf patients. Chronic Kidney disease stage will also be calculated automatically and shown in the ‘CKD stage’ column. Stage 5 being the most severe corresponds to a GFR value of 0 – 14; Stage 4 corresponds to a GFR value of 15 – 29; Stage 3 corresponds to a GFR value of 30 – 59; Stage 2 corresponds to a GFR value of 60 – 89; and Stage 1 being the least severe corresponds to a GFR value of 90+.

  14. Figure 9

  15. Cells with incorrect data will get marked with a grey background colour and the error description is displayed in the ‘notes’ section (Figure 9). You can correct the invalid values indicated by the calculator, according to the error description and press the 'Calculate' button to re-calculate the eGFR values using the modified value. You may repeat this step until all the values are indicated to be valid.
  16. The list of patients and their data can be ordered based on the severity of the CKD stage by clicking on the 'Sort by CKD stage' button (figure 10).

  17. Figure 10

  18. The spreadsheet can be reset and prepared for another calculation by pressing the ‘Reset’ button.

Note: If the calculation process does not work after you have done an amendment to cell content, please click on any other cell on the same worksheet any press ‘Calculate’.