Before you enter data
Login to the National Diagnostic Reference Level Service.
NDRLS data collection
In the National Diagnostic Reference Level Survey, there are six anatomical protocols, defined by the following inferior and superior margins. Data collection is defined by three age groups and six anatomical protocols. The three age groups are:
- baby/infant (0-4 years)
- child (5-14 years)
- adult (15+ years)
The six protocols are defined by inferior and superior scan margins
For comprehensive instructions on how to enter data, download the National Diagnostic Reference Level Service User Guide:
National Diagnostic Reference Level Survey User Guide - 2016
To start a new survey you select the Age Group, Protocol and CT Scanner used from the drop down lists and then select ‘Start New Survey’.
This takes you to the data entry page for the survey you have just created. There are two main sections to this page, the scan settings data and the patient data. Before you can fill in any patient data you must fill in the scan settings data and select ‘Save Settings’.
Some settings such as ‘Reconstruction Algorithm Kernal’ and ‘Scan Field of View’ allow you to enter numbers and/or words/symbols, eg. ‘Standard’ or ‘35 cm’.
The ‘Reconstruction Slice Width’ box allows you to enter multiple widths, eg. ‘2, 5, 10’.
The comments box is a free field where any additional information can be recorded.
There is an option to print out this data entry page. It may be easier to fill in the patient data table by hand then log back in and enter the data electronically later.
In the patient data entry table, for single and multiple phase scans, the average CTDIvol, the total DLP, patient weight, patient age and patient sex is required.
To obtain the patient weight you should just ask them, accuracy to the nearest 2 kg is sufficient.
It is easiest to enter the patient data across each row rather than down each column.
Each time you select ‘Save’ or ‘Save and Close’ the patient data you have entered will become locked and you will not be able to edit it.
The ‘Show Scattergam’ button will only become active once you have saved data for at least one patient. By selecting ‘Show Scattergam’ you will be able to view a graph showing DLP vs patient number.
The ‘Submit Survey’ button will only become active once you have entered data for at least 10 patients and saved the data.
Caution: Do not select the ‘Submit Survey’ button until you are sure that you wish to submit the data. Once you submit the data the survey will become locked and you will not be able to add any additional data. A warning message will appear to ask you if you are sure you wish to submit the data.
Like all parts of the service, the webpage will time out after 10 minutes of no activity, when this happens you will have to log back in to continue.
|Anatomical Protocol - Head||Anatomical Protocol - Neck|
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|Anatomical Protocol - ChestAbdoPelvis||Anatomical Protocol - Lumbar Spine|
Further information on International Best Practice for Radiation Protection of Patients can be found on the International Atomic Energy Agency Radiation Protection of Patients website, which can be accessed via the following link: