Trial Outcomes & Findings for CT DOSE Collaboratory (NCT NCT03000751)
NCT ID: NCT03000751
Last Updated: 2024-03-08
Results Overview
We will assess the change in the mean effective dose after the simple audit and multi-component interventions (MCI) in comparison to before the audit and multi-component interventions. The numbers given below reflect absolute change in mean dose (in millisieverts) relative to the baseline period.
COMPLETED
NA
864080 participants
Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81
2024-03-08
Participant Flow
Study subjects were passively enrolled in this study; we had a waiver of informed consent and there was no direct contact with subjects. We have listed the number of unique subjects enrolled into each track; however, ALL ANALYSES WERE PERFORMED AT THE LEVEL OF THE CT SCAN, not at the individual subject level.
Unit of analysis: CT scans
Participant milestones
| Measure |
Track A
Track A received the simple audit intervention at week 40 and the multi-component intervention at week 68.
The simple audit provided feedback on radiation doses including comparison with other participating sites. The multi-component intervention gave tailored, actionable feedback on needed changes in addition to a 7-week quality improvement collaborative that included guidance on quality improvement methods, webinars, interactive lectures by experts, case reviews, and best practices sharing.
|
Track B
Track B received the simple audit intervention at week 44 and the multi-component intervention at week 74.
The simple audit provided feedback on radiation doses including comparison with other participating sites. The multi-component intervention gave tailored, actionable feedback on needed changes in addition to a 7-week quality improvement collaborative that included guidance on quality improvement methods, webinars, interactive lectures by experts, case reviews, and best practices sharing.
|
Track C
Track C received the simple audit intervention at week 53 and the multi-component intervention at week 81.
The simple audit provided feedback on radiation doses including comparison with other participating sites. The multi-component intervention gave tailored, actionable feedback on needed changes in addition to a 7-week quality improvement collaborative that included guidance on quality improvement methods, webinars, interactive lectures by experts, case reviews, and best practices sharing.
|
|---|---|---|---|
|
Overall Study
STARTED
|
251607 327,462
|
229022 306,825
|
383451 522,370
|
|
Overall Study
COMPLETED
|
251607 327,462
|
229022 306,825
|
383451 522,370
|
|
Overall Study
NOT COMPLETED
|
0 NA
|
0 NA
|
0 NA
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
CT DOSE Collaboratory
Baseline characteristics by cohort
| Measure |
Baseline Period
n=526439 CT scans
Reflects CT scans analyzed during a baseline period of usual care (before intervention). The duration of this period differed by randomization Track (A, B, or C).
|
Simple Audit Intervention Period
n=251409 CT scans
Reflects CT scans analyzed after receiving the simple audit report intervention. The duration of this period differed by randomization Track (A, B, or C).
|
Multi-component Intervention Period
n=207576 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention. The duration of this period differed by randomization Track (A, B, or C).
|
Total
n=985424 CT scans
Total of all reporting groups
|
|---|---|---|---|---|
|
Age, Customized
18-29 years
|
40022 CT scans
n=526439 CT scans
|
18468 CT scans
n=251409 CT scans
|
15391 CT scans
n=207576 CT scans
|
73881 CT scans
n=985424 CT scans
|
|
Age, Customized
30-39 years
|
45880 CT scans
n=526439 CT scans
|
21198 CT scans
n=251409 CT scans
|
17615 CT scans
n=207576 CT scans
|
84693 CT scans
n=985424 CT scans
|
|
Age, Customized
40-49 years
|
64299 CT scans
n=526439 CT scans
|
29492 CT scans
n=251409 CT scans
|
24351 CT scans
n=207576 CT scans
|
118142 CT scans
n=985424 CT scans
|
|
Age, Customized
50-59 years
|
98457 CT scans
n=526439 CT scans
|
46589 CT scans
n=251409 CT scans
|
37951 CT scans
n=207576 CT scans
|
182997 CT scans
n=985424 CT scans
|
|
Age, Customized
60-69 years
|
114161 CT scans
n=526439 CT scans
|
54155 CT scans
n=251409 CT scans
|
44102 CT scans
n=207576 CT scans
|
212418 CT scans
n=985424 CT scans
|
|
Age, Customized
70-79 years
|
92374 CT scans
n=526439 CT scans
|
45969 CT scans
n=251409 CT scans
|
39073 CT scans
n=207576 CT scans
|
177416 CT scans
n=985424 CT scans
|
|
Age, Customized
80 years and older
|
71246 CT scans
n=526439 CT scans
|
35538 CT scans
n=251409 CT scans
|
29093 CT scans
n=207576 CT scans
|
135877 CT scans
n=985424 CT scans
|
|
Sex: Female, Male
Female
|
278841 CT scans
n=526439 CT scans
|
132772 CT scans
n=251409 CT scans
|
110088 CT scans
n=207576 CT scans
|
521701 CT scans
n=985424 CT scans
|
|
Sex: Female, Male
Male
|
247598 CT scans
n=526439 CT scans
|
118637 CT scans
n=251409 CT scans
|
97488 CT scans
n=207576 CT scans
|
463723 CT scans
n=985424 CT scans
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
Asian
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
Black or African American
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
White
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
More than one race
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
NA CT scans
n=526439 CT scans
|
NA CT scans
n=251409 CT scans
|
NA CT scans
n=207576 CT scans
|
NA CT scans
n=985424 CT scans
|
|
Type of scan
Abdomen
|
185671 CT scans
n=526439 CT scans
|
87518 CT scans
n=251409 CT scans
|
72084 CT scans
n=207576 CT scans
|
345273 CT scans
n=985424 CT scans
|
|
Type of scan
Chest
|
143120 CT scans
n=526439 CT scans
|
69678 CT scans
n=251409 CT scans
|
56410 CT scans
n=207576 CT scans
|
269208 CT scans
n=985424 CT scans
|
|
Type of scan
Combined abdomen and chest
|
30689 CT scans
n=526439 CT scans
|
14784 CT scans
n=251409 CT scans
|
14416 CT scans
n=207576 CT scans
|
59889 CT scans
n=985424 CT scans
|
|
Type of scan
Head
|
166959 CT scans
n=526439 CT scans
|
79429 CT scans
n=251409 CT scans
|
64666 CT scans
n=207576 CT scans
|
311054 CT scans
n=985424 CT scans
|
|
Age, by type of scan
Abdomen
|
56.0 Years
STANDARD_DEVIATION 18.2 • n=526439 CT scans
|
56.3 Years
STANDARD_DEVIATION 18.3 • n=251409 CT scans
|
56.4 Years
STANDARD_DEVIATION 18.3 • n=207576 CT scans
|
56.2 Years
STANDARD_DEVIATION 18.3 • n=985424 CT scans
|
|
Age, by type of scan
Chest
|
61.6 Years
STANDARD_DEVIATION 15.3 • n=526439 CT scans
|
62.1 Years
STANDARD_DEVIATION 15.2 • n=251409 CT scans
|
62.0 Years
STANDARD_DEVIATION 15.2 • n=207576 CT scans
|
61.8 Years
STANDARD_DEVIATION 15.2 • n=985424 CT scans
|
|
Age, by type of scan
Combined abdomen and chest
|
62.5 Years
STANDARD_DEVIATION 15.3 • n=526439 CT scans
|
62.8 Years
STANDARD_DEVIATION 15.5 • n=251409 CT scans
|
63.4 Years
STANDARD_DEVIATION 15.4 • n=207576 CT scans
|
62.8 Years
STANDARD_DEVIATION 15.4 • n=985424 CT scans
|
|
Age, by type of scan
Head
|
60.1 Years
STANDARD_DEVIATION 19.9 • n=526439 CT scans
|
60.7 Years
STANDARD_DEVIATION 19.9 • n=251409 CT scans
|
60.6 Years
STANDARD_DEVIATION 19.9 • n=207576 CT scans
|
60.4 Years
STANDARD_DEVIATION 19.9 • n=985424 CT scans
|
|
Patient diameter
Abdomen
|
30.7 Centimeters (cm)
STANDARD_DEVIATION 4.6 • n=526439 CT scans
|
30.8 Centimeters (cm)
STANDARD_DEVIATION 4.7 • n=251409 CT scans
|
30.9 Centimeters (cm)
STANDARD_DEVIATION 4.7 • n=207576 CT scans
|
30.8 Centimeters (cm)
STANDARD_DEVIATION 4.7 • n=985424 CT scans
|
|
Patient diameter
Chest
|
28.9 Centimeters (cm)
STANDARD_DEVIATION 4.9 • n=526439 CT scans
|
29.0 Centimeters (cm)
STANDARD_DEVIATION 4.9 • n=251409 CT scans
|
28.9 Centimeters (cm)
STANDARD_DEVIATION 5.1 • n=207576 CT scans
|
28.9 Centimeters (cm)
STANDARD_DEVIATION 5.0 • n=985424 CT scans
|
|
Patient diameter
Combined abdomen and chest
|
29.7 Centimeters (cm)
STANDARD_DEVIATION 4.1 • n=526439 CT scans
|
29.5 Centimeters (cm)
STANDARD_DEVIATION 4.2 • n=251409 CT scans
|
29.7 Centimeters (cm)
STANDARD_DEVIATION 4.2 • n=207576 CT scans
|
29.7 Centimeters (cm)
STANDARD_DEVIATION 4.2 • n=985424 CT scans
|
|
Patient diameter
Head
|
17.1 Centimeters (cm)
STANDARD_DEVIATION 1.5 • n=526439 CT scans
|
17.1 Centimeters (cm)
STANDARD_DEVIATION 1.5 • n=251409 CT scans
|
17.2 Centimeters (cm)
STANDARD_DEVIATION 1.5 • n=207576 CT scans
|
17.1 Centimeters (cm)
STANDARD_DEVIATION 1.5 • n=985424 CT scans
|
PRIMARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: The unit of analysis is CT scans; there were no data collected at the participant level. We excluded scans obtained during transition ("washout") periods immediately following each intervention. The numbers given below reflect absolute change in mean dose (in millisieverts) relative to the baseline period.
We will assess the change in the mean effective dose after the simple audit and multi-component interventions (MCI) in comparison to before the audit and multi-component interventions. The numbers given below reflect absolute change in mean dose (in millisieverts) relative to the baseline period.
Outcome measures
| Measure |
Simple Audit Intervention Period
n=251409 CT scans
Reflects CT scans analyzed after receiving the simple audit report intervention.
|
Multi-component Intervention Period
n=207576 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
Multi-component Intervention Period
Reflects CT scans analyzed after receiving the multi-component intervention.
|
|---|---|---|---|
|
Change in Mean Effective Dose (ED)
Abdomen
|
-0.13 Millisieverts (mSv)
Interval -0.24 to -0.02
|
-0.81 Millisieverts (mSv)
Interval -0.99 to -0.64
|
—
|
|
Change in Mean Effective Dose (ED)
Chest
|
-0.14 Millisieverts (mSv)
Interval -0.23 to -0.05
|
-0.26 Millisieverts (mSv)
Interval -0.4 to -0.11
|
—
|
|
Change in Mean Effective Dose (ED)
Combined abdomen and chest
|
-0.88 Millisieverts (mSv)
Interval -1.18 to -0.57
|
-2.04 Millisieverts (mSv)
Interval -2.55 to -1.53
|
—
|
|
Change in Mean Effective Dose (ED)
Head
|
-0.01 Millisieverts (mSv)
Interval -0.06 to 0.04
|
-0.05 Millisieverts (mSv)
Interval -0.13 to 0.02
|
—
|
PRIMARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: The unit of analysis is CT scans; there were no data collected at the participant level. We excluded scans obtained during transition ("washout") periods immediately following each intervention.
We will assess the change in the percentage of examinations with an effective dose above the benchmark after the simple audit and after multi-component intervention (MCI) in comparison to doses before the audit and MCI. The benchmark for each anatomic area is defined as the 75th percentile of the dose distribution during the pre-intervention (baseline) period.
Outcome measures
| Measure |
Simple Audit Intervention Period
n=526439 CT scans
Reflects CT scans analyzed after receiving the simple audit report intervention.
|
Multi-component Intervention Period
n=251409 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
Multi-component Intervention Period
n=207576 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
|---|---|---|---|
|
Percentage of CT Scans With an Effective Dose Above Benchmark
Head
|
26.2 Percent of CT scans over benchmark
|
26 Percent of CT scans over benchmark
|
21.8 Percent of CT scans over benchmark
|
|
Percentage of CT Scans With an Effective Dose Above Benchmark
Abdomen
|
24.7 Percent of CT scans over benchmark
|
24.7 Percent of CT scans over benchmark
|
22.2 Percent of CT scans over benchmark
|
|
Percentage of CT Scans With an Effective Dose Above Benchmark
Chest
|
26 Percent of CT scans over benchmark
|
25.5 Percent of CT scans over benchmark
|
24.9 Percent of CT scans over benchmark
|
|
Percentage of CT Scans With an Effective Dose Above Benchmark
Combined chest and abdomen
|
26.7 Percent of CT scans over benchmark
|
23 Percent of CT scans over benchmark
|
18.8 Percent of CT scans over benchmark
|
SECONDARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: Data were not collected.
We will assess the change in the dose length product after the audit and MCI in comparison to before the audit and MCI.
Outcome measures
Outcome data not reported
SECONDARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: Data were not collected.
We will assess the change in the proportion of examinations with a dose length product above the benchmark after the audit and after the MCI in comparison to doses before the audit and MCI. The benchmark for each anatomic area is defined as the 75th percentile of the dose distribution during the pre intervention period.
Outcome measures
Outcome data not reported
SECONDARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: The unit of analysis is CT scans; there were no data collected at the participant level. We excluded scans obtained during transition ("washout") periods immediately following each intervention. The numbers given below reflect absolute change in mean dose (in milligray, mGy) relative to the baseline period.
We will assess the change in the mean volume CT dose index (CTDIvol) from before versus after the audit and MCI intervention. CTDIvol (in units of milligray, mGy) is a measure of radiation dose, reflecting the amount of radiation imparted per CT slice by the scanner. Higher CTDIvol signifies more radiation dose. In general, a reduction in CTDIvol would be a sign of quality improvement, minimizing excess radiation exposure to the patient.
Outcome measures
| Measure |
Simple Audit Intervention Period
n=251409 CT scans
Reflects CT scans analyzed after receiving the simple audit report intervention.
|
Multi-component Intervention Period
n=207576 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
Multi-component Intervention Period
Reflects CT scans analyzed after receiving the multi-component intervention.
|
|---|---|---|---|
|
Change in Mean Volume Computed Tomography Dose Index (CTDIvol)
Abdomen
|
0.09 Milligrays (mGy)
Interval 0.01 to 0.16
|
0.03 Milligrays (mGy)
Interval -0.1 to 0.15
|
—
|
|
Change in Mean Volume Computed Tomography Dose Index (CTDIvol)
Chest
|
0.04 Milligrays (mGy)
Interval -0.07 to 0.14
|
-0.11 Milligrays (mGy)
Interval -0.29 to 0.06
|
—
|
|
Change in Mean Volume Computed Tomography Dose Index (CTDIvol)
Combined abdomen and chest
|
-0.05 Milligrays (mGy)
Interval -0.18 to 0.08
|
-0.42 Milligrays (mGy)
Interval -0.64 to -0.2
|
—
|
|
Change in Mean Volume Computed Tomography Dose Index (CTDIvol)
Head
|
0.44 Milligrays (mGy)
Interval 0.27 to 0.62
|
-0.56 Milligrays (mGy)
Interval -0.85 to -0.27
|
—
|
SECONDARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: The unit of analysis is CT scans; there were no data collected at the participant level. We excluded scans obtained during transition ("washout") periods immediately following each intervention.
We will assess the change in the percentage of examinations with a CTDIvol above the benchmark after the audit and after multicomponent intervention in comparison to doses before the audit and multicomponent intervention. The benchmark for each anatomic area is defined as the 75th percentile of the dose distribution during the pre intervention period.
Outcome measures
| Measure |
Simple Audit Intervention Period
n=526439 CT scans
Reflects CT scans analyzed after receiving the simple audit report intervention.
|
Multi-component Intervention Period
n=251409 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
Multi-component Intervention Period
n=207576 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
|---|---|---|---|
|
Percentage of CT Scans With a CTDIvol Above Benchmark
Abdomen
|
24.5 Percentage of CT scans
|
24.9 Percentage of CT scans
|
24.1 Percentage of CT scans
|
|
Percentage of CT Scans With a CTDIvol Above Benchmark
Chest
|
26 Percentage of CT scans
|
25.8 Percentage of CT scans
|
24.1 Percentage of CT scans
|
|
Percentage of CT Scans With a CTDIvol Above Benchmark
Combined chest and abdomen
|
23.6 Percentage of CT scans
|
22.7 Percentage of CT scans
|
19.9 Percentage of CT scans
|
|
Percentage of CT Scans With a CTDIvol Above Benchmark
Head
|
24.4 Percentage of CT scans
|
25.0 Percentage of CT scans
|
17.9 Percentage of CT scans
|
SECONDARY outcome
Timeframe: Sites were randomized to 1 of 3 tracks, which determined the timing of intervention: Track A: audit at week 40, MCI at week 68 Track B: audit at week 44, MCI at week 74 Track C: audit at week 53, MCI at week 81Population: The unit of analysis is CT scans; there were no data collected at the participant level. We excluded scans obtained during transition ("washout") periods immediately following each intervention. The numbers given below reflect absolute change in mean dose (in millisieverts) relative to the baseline period.
We will assess the change in organ doses after the simple audit and multi-component interventions (MCI) in comparison to before the audit and multi-component interventions. The numbers given below reflect absolute change in mean dose (in millisieverts) relative to the baseline period.
Outcome measures
| Measure |
Simple Audit Intervention Period
n=251409 CT scans
Reflects CT scans analyzed after receiving the simple audit report intervention.
|
Multi-component Intervention Period
n=207576 CT scans
Reflects CT scans analyzed after receiving the multi-component intervention.
|
Multi-component Intervention Period
Reflects CT scans analyzed after receiving the multi-component intervention.
|
|---|---|---|---|
|
Change in Mean Organ Doses: Brain Dose for Head CT; Lung Dose For Chest CT; Colon and Liver Dose for Abdomen CT
Abdomen (colon organ dose)
|
-6.0 Milligrays (mGy)
Interval -6.9 to -5.0
|
-12.2 Milligrays (mGy)
Interval -13.8 to -10.6
|
—
|
|
Change in Mean Organ Doses: Brain Dose for Head CT; Lung Dose For Chest CT; Colon and Liver Dose for Abdomen CT
Chest (lung organ dose)
|
-2.1 Milligrays (mGy)
Interval -2.8 to -1.5
|
-3.7 Milligrays (mGy)
Interval -4.7 to -2.7
|
—
|
|
Change in Mean Organ Doses: Brain Dose for Head CT; Lung Dose For Chest CT; Colon and Liver Dose for Abdomen CT
Combined chest and abdomen (lung organ dose)
|
-16.0 Milligrays (mGy)
Interval -18.2 to -13.8
|
-30.1 Milligrays (mGy)
Interval -33.8 to -26.4
|
—
|
|
Change in Mean Organ Doses: Brain Dose for Head CT; Lung Dose For Chest CT; Colon and Liver Dose for Abdomen CT
Combined chest and abdomen (colon organ dose)
|
-13.0 Milligrays (mGy)
Interval -14.5 to -11.6
|
-17.6 Milligrays (mGy)
Interval -20.0 to -15.1
|
—
|
|
Change in Mean Organ Doses: Brain Dose for Head CT; Lung Dose For Chest CT; Colon and Liver Dose for Abdomen CT
Head (brain organ dose)
|
-2.9 Milligrays (mGy)
Interval -6.4 to 0.7
|
-7.5 Milligrays (mGy)
Interval -13.3 to -1.7
|
—
|
Adverse Events
Track A
Track B
Track C
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Rebecca Smith-Bindman, MD
University of California San Francisco
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place