News headlines from across Canada are periodically dominated by scandals and errors in diagnostic imaging. The list grows each year, with errors exposed from coast to coast.

The narrative follows the same arc – an error is discovered in an area of diagnostic imaging. A radiologist – generally the physician involved in the interpretation of diagnostic imaging results – is disciplined or dismissed, followed by calls to improve quality assurance in diagnostic imaging.

However, there are technical and practical challenges to putting in place robust systems to monitor and improve the quality of diagnostic imaging services and providers.

Healthy Debate spoke to radiologists from across Canada and decision makers who are leading the implementation of these systems to understand the challenges and opportunities in quality assurance for diagnostic imaging.

Errors uncovered at Trillium Health Partners

Earlier this month, one radiologist at Trillium Health Partners was found to have made errors in interpreting at least three computed tomography (CT) scans and mammograms.

This has prompted the removal of that radiologist’s privileges to practice, as well as an investigation of his work by the College of Physicians and Surgeons of Ontario.

In response Trillium Health Partners has initiated a massive review and outreach effort to thousands of patients who had scans read by this radiologist.

However, patient safety experts have long agreed that it is usually not “bad people” that lead to errors in health care, but rather “bad systems.”

Robert Sevick, head of the University of Calgary Department of Radiology, points to a need for systems to reduce human error. “Are radiologists making errors? Of course they are. We are human and humans make errors. It doesn’t help them to be attacked in the media and singled out.”

Sevick characterizes this as a “destructive way of dealing with the problem” and proposes that a quality assurance system for radiology needs to have a “supportive and educational structure, rather than punitive.”

In the wake of the Trillium news, Ontario decision makers have expressed an interest in  improving quality assurance systems for radiology.

Currently, British Columbia and Alberta are the only Canadian provinces putting in place province-wide quality assurance systems for diagnostic imaging. In all other provinces, quality assurance is done on a “hospital by hospital, and practice by practice, ad hoc basis” according to Sevick.

Why is quality assurance in diagnostic imaging so difficult?

The first challenge is that there is a debate within the field around the acceptable rate of error associated with reading diagnostic imaging.

Alan Moody, chair of the department of medical imaging at the University of Toronto notes that “the figures for missed rates are not translatable across different specialties [within radiology].”

Diagnostic imaging is a massive field. Technologies like ultrasounds and MRIs are widely used for diagnosing or assessing diseases in many medical specialties. While radiologists receive specialist training to read and interpret diagnostic imaging tests of the body, it is also a rapidly evolving field with new technologies being introduced continuously.

For example, the output of a CT scan, which uses x-rays to produce images of slices from areas of the body, has increased significantly. Sevick notes that “the amount of data to be processed is a quantum leap above where it used to be.” He gives the example of a CT scan of the head. He says in the 1980s this test would have an output of 15 images printed on 2 films; and today it is 100’s of digital images.

Doug Cochrane, chair of the BC Patient Safety and Quality Council, and lead investigator in a review of the quality of diagnostic imaging in BC notes that this is both a blessing and challenge to the field.

Cochrane raised concerns in his 2011 report around the challenges for practicing radiologists, as well as radiology training programs, “to keep up with these changes whilst ensuring competency.”

Radiologists also practice in many different settings, with more specialized radiologists based in large teaching hospitals. Generalist radiologists tend to practice in community hospitals or smaller communities. Almost one half of Canadian radiologists work in a private office or clinic, with about the other half working in community or academic hospitals. About 70% of radiologists work in a group practice, meaning they share responsibilities, equipment and office space. However, about 14% of radiologists work in solo practice settings.

Chris Molnar, Zone Division Chief of Nuclear Medicine in Calgary notes that increased specialization has implications for clinical practice, depending on where radiologists work.

“I might see something on a chest CT I don’t understand so I can phone or page a colleague to ask their opinion” she says. Molnar notes that the practice setting influences how radiologists can consult with colleagues when they have a problem or question. “If you are working in a small community hospital, who do you phone for help when you have a rare or difficult case?” she asks.

Radiologists are faced with reading significant volumes of diagnostic imaging scan outputs. There are growing volumes both of diagnostic tests being ordered, and the outputs of these tests.

A recent publication by three Toronto radiologists reported that the total number of images their radiology department interpreted on a daily basis has doubled every 4.5 years. A 2011 Canadian Institute of Health Information report identified that the number of magnetic resonance imaging (MRI) and CT scans had doubled within six years across Canada.

Radiologists also work under significant time pressures. Most hospitals in Canada measure the turnaround time for radiologists’ reports. Molnar suggests part of a radiologists’ role on a clinical team is to “provide an answer quickly.” However she reflects – “if you are measuring time but no other performance indicators, you get a distorted incentive driver.”

In this context, what are the best approaches to putting in place quality assurance programs for diagnostic imaging?

Systems for Quality Assurance in Diagnostic Imaging

There are no national quality assurance standards for diagnostic imaging in Canada.

Approaches to quality assurance vary based on factors like the practice setting, type of diagnostic imaging being used and number of radiologists in a practice.

Wade Hillier, Director of the Quality Management Division of the College of Physicians and Surgeons of Ontario notes that there are a number of different approaches to ensuring quality in the practices of radiologists within their practice settings, which vary depending on “resources and commitment”.

While the College conducts assessments of radiologists and their facilities when they practice outside hospitals, in Independent Health Facilities, this is different than having two radiologists consult on a difficult case or image. Hillier suggests that peer to peer review, or second read of diagnostic images “flows up from the profession itself.”

In 2011, the Canadian Association of Radiologists published a Guide to Peer Review Systems which sets outs requirements for components of peer review processes, and provides suggestions on how  processes could be integrated into daily practice. However, one radiologist informant noted that the Association lacks both “teeth and dollars” to enforce or implement such processes.

Provincial Quality Assurance Systems for Diagnostic Imaging

However, some provinces are taking a leadership role in establishing quality assurance systems.

In 2011, as a response to concerns about the quality of diagnostic imaging by four radiologists in British Columbia, the provincial government launched a review on the quality of diagnostic imaging in that province.

The findings of this review led to 35 recommendations, intended to address the concerns that prompted the review, as well as improve quality assurance systems in that province. This includes setting up a peer review system where images can be concurrently reviewed by two or more radiologists. This system is currently being piloted in one of BC’s health authorities, Vancouver Coastal Health.

Cochrane, who led the review notes that these programs are difficult to set up because hospitals rely on different medical technology applications in diagnostic imaging, known as Radiology Information Systems (RIS) and Picture archiving and communication system (PACS).  “Health care in BC has systems set up that don’t talk to each other” he says.

Alberta is following in BC’s footsteps, after mistakes in diagnostic imaging were found at the Drumheller Hospital in 2011. Part of Alberta Health Services’ response has been to put out a request for proposals from technology companies around a province-wide, concurrent peer review system.

Mauro Chies, Acting Vice President of Clinical Supports for Alberta Health Services notes that an advantage of a single health authority is that the province’s hospitals share the same RIS and PACS applications. The absence of technical roadblocks means that “we can send images from one corner of the province to another.” He says that implementing this system is a top priority for his office, and plans for it to be operational across the province by summer 2014.

In response to the errors uncovered at Trillium Health Partners, Ontario is considering putting in place stronger systems of peer review for diagnostic imaging.

Sheamus Murphy, a spokesperson for Ontario’s Minister of Health Deb Matthews stated that the Minister has met with provincial hospital, medical and radiology representatives to discuss quality assurance in diagnostic imaging. He noted that “those around the table all agreed, including radiologists themselves, [that] we could do more to ensure quality in radiology.”

“Peer review is one of the steps we are giving serious consideration to” says Murphy.

Radiologists are well aware that it is easier to assess their performance than it is for other medical specialties. There is some tension around having province-wide systems in place to assess quality, when this was previously left up to the profession. However, given the growing complexity in diagnostic imaging, and growing need for radiologists’ services, systems to measure and monitor quality seem inevitable.

The 2011 Canadian Association of Radiologists guide states “radiology is at a crossroads of rapid technological advance and globalization; with the advent of PACS and off-site on call service provision, radiologists need to embrace quality assurance not only to safeguard patients but to safeguard their own profession.”