Nuclear medicine survey statistics

This page contains usage statistics and a summary of the data submitted to the NDRLS nuclear medicine survey.

If you are conducting a publicly funded research project and would like to gain access to an anonymised version of the NDRLS MDCT dataset, please contact the NDRLS team.

Data sources

The DRLs were derived from two data sources. The first was a survey of Australian nuclear medicine facilities conducted in 2014/15 (the NDRLS survey). We asked participating facility to report every dose (from both radiopharmaceutical and CT sources) delivered within their department over a four week period. The median of the doses delivered at each facility (termed the facility reference level, or FRL) was calculated for each protocol reported. If a facility conducted a procedure four or more times, the FRL was included in the DRL calculation. A DRL was calculated using the NDRLS survey data for all procedures with at least four FRLs. From this data, DRLs for fifteen general nuclear medicine procedures, three PET protocols, three PET/CT scan regions and seven SPECT/CT scan regions were defined.

The second source of data was an extensive survey conducted on behalf of the ANZSNM in 2008 (Diagnostic Reference Activities for Nuclear Medicine Procedures in Australia and New Zealand). Rather than request details of individual administrations, the ANZSNM survey asked participants to enter the doses prescribed for each of their protocols. The ANZSNM then published the most common activity (MCA) reported for over 70 different nuclear medicine and PET protocols.

There were a number of protocols listed in the ANZSNM table that did not receive enough data in the NDRLS survey to derive a DRL. In these cases, the ANZSNM data was reanalysed using the reported activity at each site as the FRL. The ANZSNM data accounted for around 50 of the general nuclear medicine DRLs.

DRL metrics and calculation methodology

The metric chosen to define the DRLs was the 75th percentile of the FRL distribution, keeping the nuclear medicine DRLs consistent with the CT DRLs already published by ARPANSA. In addition to the DRL, the 50th and 25th percentiles of the distributions were also calculated.

The methodology used to calculate the DRLs is demonstrated using bone scans as an example in Figure 1:

  1. Top left: A histogram of the age and gender of the patients scanned. Only adult patients were considered (arbitrarily defined as patients over the age of 15).
  2. Top right: A histogram of the activities administered to individual patients. Each different colour/shading represents patients at a different facility. The green, blue and red lines represent the 25th, 50th and 75th percentiles of the administered activity respectively.
  3. Bottom left: A scatter plot of the activity administered to individual patients as a function of weight. Each different marker colour/shape represents a different facility. Not all facilities provided the weight of every patient – the scatter plots therefore do not necessarily include every patient. The green, blue and red lines represent the 25th, 50th and 75th percentiles of the administered activity respectively (from the top right figure). This plot was used to determine if weight correction was regularly employed (no in the case of bone scans).
  4. Bottom right: A histogram of the median dose administered at each facility. This is known as the facility reference level (FRL). The green, blue and red lines represent the 25th, 50th and 75th percentiles of the FRL distribution, and are the basis of the DRLs. The colour of the histogram bins is indicative of the number of individual scans conducted at the facility with the given FRL – the darker the colour, the more scans conducted.

Bone scan data submitted to the NDRLS

Figure 1: The bone scan data submitted to the NDRLS survey

A similar methodology was used to set the DRLs for PET scans where weight correction wasn’t commonplace and the DRLs for the CT component of SPECT/PET scans.

Community participation

ARPANSA sent invitations to participate in the NDRLS survey to 175 imaging facilities throughout the ACT, NSW, the NT, SA, Tasmania, and Victoria. The state regulators for Queensland and WA sent invitations to their licensees on behalf of ARPANSA. Seventy-eight facilities participated in the survey, which ARPANSA estimates represents a third of all nuclear medicine facilities within Australia. Figure 2 shows the number of invitations sent, the number of facilities that enrolled in the survey and the number of those facilities that submitted data to the survey.

Community participation - nuclear medicine DRLs

Figure 2

The two tables below categorise the number of facilities by the facility type and the submission type.

Table 1: The type of facilities that participated in the NDRLS survey
Facility type Number of facilities
Public 45
Private in public 26
Private 7
Table 2: The number of facilities that submitted data and the number of scans submitted, categorised by modality and age group.
  Adult Paediatric
Number of facilities Number of scans Number of facilities Number of scans
General nuclear medicine 76 11815 38 414
Nuclear medicine/CT 62 5835 15 49
PET 19 3739 7 64
PET/CT 19 4108 7 65

Submitted data

Summaries of the number of surveys submitted are presented in tables 3 and 4. The FRL distribution for all protocols (including those gathered as part of the 2008 ANZSNM survey) can be accessed by clicking the entries in the DRL tables on the Current NM DRLs page.

Table 3: The general nuclear medicine protocols reported by NDRLS survey participants. Only the protocols that were used to develop the DRLs are shown.
Category Scan Radiopharmaceutical Number of facilities Number of scans
Cardiac Gated blood pool scan Tc_99m RBCs 37 443
MPI - 1 day rest + stress Tc_99m MIBI 56 1709
MPI - single phase Tc_99m MIBI 22 583
Endocrine Parathyroid Tc_99m MIBI 24 150
Parathyroid subtraction Tc_99m Pertechnetate 13 79
Thyroid Tc_99m Pertechnetate 60 670
Gastrointestinal Gastric emptying Tc_99m Colloid, DTPA 11 70
Genitourinary Renal scan Tc_99m DTPA 8 45
Tc_99m MAG3 15 137
Hepatobiliary Hepatobiliary Tc_99m HIDA/DISIDA 15 97
Infection Infection Ga_67 Citrate 9 65
Lymphatic Lymphoscintigraphy Tc_99m Colloid 37 449
Nervous system Brain Tc_99m HMPAO/ECD 9 110
Pulmonary Lung perfusion Tc_99m MAA 57 829
Skeletal Bone scan Tc_99m MDP/HDP 73 5244
Table 4: The PET protocols reported by NDRLS survey participants. Only the protocols that were used the develop the DRLs are shown.
Category Radiopharmaceutical Number of facilities Number of scans
Body F_18 FDG 6 697
Body (weight corrected) F_18 FDG 13 2655
Brain F_18 FDG 5 52
Ga-68 Ga_68 7 255