Improving Inclusion of Comparison Studies in Radiology Interpretations
PQI Project



Gap: A comprehensive satisfaction survey of physicians that refer patients for imaging revealed an opportunity for improvement regarding referencing prior comparison studies in the interpretation of new studies. This feedback was the most consistent across all radiology subspecialties. Comparing with prior imaging is a very useful adjunct in assessing the chronicity of imaging findings and thus limiting the provided differential diagnosis. Utilizing comparison studies has a direct impact on patient care since broad differential diagnoses, as well as indeterminate findings, typically warrant additional imaging or clinical investigation, some of which may be avoided.


Target: The target is to have a 20% improvement or achieve > 80% of radiology interpretations having either a comparison to a prior study, when available, or document that there were no prior studies for comparison.


Timeline: This project is expected to take a minimum of 3 months to complete.


Stakeholder analysis and input: Obtaining stakeholder input from referring physicians and from radiology staff members is encouraged at the beginning of the project.


Potential impact: This project aligns with institutional goals of providing the best care to every patient. Failing to compare radiological studies to prior studies can cause unneeded procedures and additional imaging for patients, exposes the institution to legal risk, and can delay appropriate patient care.





Baseline: At baseline, <<your baseline rate entered here>> % of radiology reports included some reference to a prior study.


Data Source: The radiology imaging electronic medical record was searched using the relevant program to establish the rate of documentation of comparison studies in all types of radiology reports. All radiology reports in the designated time period can be searched for containing any form of the word compare (comparison, comparisons, compare, compared, compares), prior(s), change or since. Reports using the word "since" would be manually reviewed to confirm that the word was used in reference to comparing with a prior exam. Alternatively, if a particular word is always used in reference to a comparison study, only that word can be used in the search parameters.


Sample Size: The baseline sample size is 25 or more radiology reports.


Counterbalance Measure: Since searching for, retrieving, and reviewing prior studies takes time to complete, an optional countermeasure would be that the report turnaround time (time from images available to report finalized) would not increase by more than 10%. Having radiology reports rapidly available to referring physician is a high satisfier for the referring physicians and is, of course, very important for timely patient care.





Factors contributing to gap: The following are common contributors to the gap in performance. Each diplomate will identify the gaps present in their own practice.
• Referring physicians request that outside imaging is available but they don't actually know when or if those images are provided.
• Radiologist unaware of prior study
• Comparison study is not yet or not ever made available to the radiologist
• Radiologist aware of prior study but did not compare
• Comparison was archived and thus would take extra time to retrieve
• Radiologist was too pressed for time to wait for comparison to be retrieved
• Technical error causing study retrieval to fail
• Images were so old that they have been purged and cannot be retrieved
• Comparing would take far more time than just interpreting the current study (ex. abdomen radiograph has 6 outside body CT and MRI exams)
• Comparison to prior is irrelevant (ex. procedural reports)
• Radiologist did compare but did not document in report
• Radiologist feels that comparison to relevant priors is implied
• Radiologist feels it takes too long to document the date of the prior study
• Radiologist feels that if a study is normal now then it doesn't matter if the prior study was abnormal
• Radiologist feels that documenting review of priors in the report is not important


Rationale for choosing interventions: Review of the factors contributing to gap will be used to choose each intervention. Each radiology practice will have unique challenges, workflow and suspected reasons for decreased performance. Based on this analysis, each practice will chose interventions as detailed in the Improve section.


Quality improvement methodology used: The "5 Whys" technique from the Analyze phase of the Six Sigma DMAIC process will be utilized to assess reasons prior studies were not commented on in radiology reports while reviewing a sample set of baseline radiology reports that did not include reference to a comparison. At least two rapid, sequential Plan-Do-Study-Act (PDSA) cycles will be utilized to improve performance.





Interventions implemented: The following are common interventions implemented. Each diplomate will customize interventions in their own practice.
• Revised all default templates to include a "Comparison: []" heading
• Analyze and discussed data as a group including relevant technologists and film library staff
• Leadership communication regarding expectation to include comparisons
• Implemented automatic pre-fetch of outside films in PACS
• Reviewed and modified PACS retrieval logic for studies


Comparison group: The comparison group is the individual's baseline performance. The diplomate will also be able to view their performance compared with a running average of others completing this project nationally via the web site.


Re-measurement results:
• After the first PDSA cycle, compliance was <<your first re-measurement rate entered here>> %
• After the second PDSA cycle, compliance was <<your second re-measurement rate entered here>> %
• Additional PDSA cycles can be optionally performed


Outcome measure: An optional repeat survey of the referring physicians who initially provided stakeholder input regarding the inclusion of comparison studies can be undertaken to assess whether they had perceived any change in performance.




Lessons learned: Common lessons learned from this project are as follows. Most radiologists have a tremendous amount of pride in their work. It can be difficult to ask people to change, since this is often taken as a criticism regarding their prior work. It is of utmost importance to approach changes such as these with a receptive customer-centered attitude. Our referring physicians are our customers and if they perceive that we are not doing something they value, then we should work together to improve that perception. There is an old saying in medicine: "If you didn't write it down, it didn't happen." Of course we know that isn't true, but if we as radiologists don't document that we were looking at a prior study, then the referring physicians and patients don't know that we did.


Barriers to implementation: The most common barrier to implementation is resistance to change. Essentially all radiologists have a preferred way to dictate studies that at least slightly differs from their colleagues. These "old habits" are hard to break and it is even harder if the radiologist does not recognize or accept the value that commenting on prior studies has for our referring physicians and patients. Another challenge with implementing change in practices with voice recognition software is the need to make revisions to sometimes a large number of reporting templates.


Communication Plan: The final project results will be anonymously shared nationally on


Transition Plan: This project will be closed after successful completion with ownership to the person or group who maintains monitoring of referring provider satisfaction.


Control Plan: The percentage of radiology reports that include a reference to prior studies or that document the absence of such studies is recommended to be sampled at least annually. If a decrease in performance to baseline levels is detected, an analysis of the data should be performed to generate a plan to return to the target performance.


Financial benefits: The financial benefits are indirect but include decreased expense for un-needed additional clinical and imaging workup in response imaging findings that could have been disregarded by comparing to prior studies. Financial benefits also include decreased legal risk for imaging findings that may have been overlooked if prior studies had not been reviewed.