decision support criteria, evidenced-based, InterQual, McKesson, utilization management



  1. Mitus, A. Jacqueline MD


Purpose/objectives: InterQual evidence-based clinical decision support criteria are used by thousands of organizations in healthcare. What industry trends led to their creation, and what accounts for their longevity and widespread acceptance?


Primary practice settings(s): Hospitals, health systems, and managed care organizations.


Findings/conclusions: Although the healthcare puzzle sometimes seems too complicated for anyone to solve, passionate people with good ideas have been able to effect substantive and relatively rapid change throughout healthcare history.


Implications for case management practice:


1. Prior to the general use of consistent and rigorous utilization management, widespread care variations, excessive healthcare costs, and less-than-optimal care were the rule rather than the exception.


2. Strategically and methodically overcoming resistance to change-starting small and the expanding outward-is the key component in reinventing healthcare.


3. In the end, if a process does not make sense, it needs to change. Take on that responsibility, joining with like-minded individuals to build momentum.



Article Content

Today, thousands of people in hospitals, health plans, and government agencies use InterQual(R) evidence-based clinical decision support criteria to answer critical questions about the appropriateness of levels of care and resource use. During the last three decades, these criteria have helped define and legitimize the disciplines of utilization and care management, providing medical directors and other hospital, and health plan professionals support in making the type of objective, evidence-based decisions that define top-quality, efficient care, and leading to greater transparency and collaboration between payors and providers.


This is the story of how InterQual evolved. As healthcare struggles to address its current challenges, the story offers some fascinating lessons, most notably that a handful of people with a passionate quest for quality can change the thinking of an entire industry.


Setting the Stage

With managed care so much a part of today's experience, it may be difficult for most to remember the very different environment that existed in healthcare 30 years or so ago, before utilization management became an effective practice.


In those days, the length of time a patient would stay in the hospital setting was highly subjective, varying widely from physician to physician, hospital to hospital, and region to region. With no formal clinical evidence guiding such determinations, physicians relied largely on commonly accepted practices and their own judgment. Efficiently transitioning patients to alternative, less costly settings was not always a priority, nor was providing support for discharge planning. Consequently, it was common for patients to stay in the hospital for weeks, even months for conditions or treatments that require only a few days of hospitalization by today's standards.


The problems with this approach became painfully apparent shortly after Medicare and Medicaid were enacted as Title XVII and XIX of the Social Security Act in 1965. The following year, Medicare was implemented for more than 19 million people, and Medicaid began its multiyear phase-in. As it opened the door to medical coverage for previously uninsured populations, the government also mandated several controls over healthcare spending. However, hospitals were inadequately prepared to cope with these controls.


For example, each provider organization was required to have an admissions committee to review the medical necessity of admission, the length of stay, the discharge practice, and the necessity of the services requested by the physician. Utilization review activities were also mandated.


For guidance in making length of stay decisions, hospitals turned primarily to a book produced by the Professional Activity Study (PAS). Sponsored by several well-respected industry organizations, the PAS program analyzed historical medical records and presented length of stay and other norms by diagnosis, age, and region. Patients admitted to the hospital would be assigned the length of stay norm, which could be amended as needed. Because these norms were not based on objective criteria for determining what was appropriate for the patient, given the severity of illness or other factors, using them to guide decision-making did nothing to change utilization patterns.


To address some of these issues, other criteria sprang up in the market that sought to apply greater clinical standardization to utilization decisions. However, the criteria were nearly impossible for nurse reviewers to interpret and apply consistently because they lacked specificity.


To illustrate the challenges reviewers faced in these early stages, consider the case of a 68-year-old woman with pneumonia admitted to the hospital. Using the PAS length of stay book, a reviewer would look up the diagnosis of pneumonia, the category of age 66-plus, and take 99th percentile option: 10 days. The reviewer would place a sticker on the front of the patient's chart, indicating this information, which not only made physicians irate but also suggested that they could take 10 days to treat the patient.


The next iteration of criteria began to address the shortcomings of the earlier generation but was also rife with problems. For example, first, a reviewer needed to validate that the patient had a "positive chest x-ray," which could be interpreted in many ways that might not necessarily mean a patient has pneumonia. Second, the reviewer would look for presence of a "fever," which might be interpreted as any value higher than 98.6[degrees]. Third, the reviewer was asked to determine a shift in differential, which nurse reviewers might not be able to recognize.


Nurse reviewers across the country did their best with the resources at their disposal, all the while confronting strong resistance from physicians who were unaccustomed to their decisions being questioned and fully aware of the deficiencies riddling the current process. At the same time, Medicare began issuing retrospective payment denials with greater frequency as inappropriate services were increasingly identified, leaving patients responsible for the bills.



As director of nursing at a Boston hospital, Joanne Lamprey was aware of the utilization review conflicts, although she had not experienced the situation directly. When she took a job as a utilization review nurse and medical audit analyst for a new hospital in 1974, she quickly received first-hand experience.


After I was introduced to the hospital, I had physicians stop me in the hall and tell me that they did not want me there, that they didn't want any nurse coming from Boston telling them what to do. (J. Lamprey, personal communication, July 12, 2007). I would thank them politely, take their names, and walk on.


Her first assignment: assess the patients who had been in the hospital for longer than 6 months. Early on, Lamprey recognized the issues with the existing criteria for examining length of stay. "Frankly, I just stopped using the books that made no sense to me. I would look at a patient and say, 'This person is walking around the halls and going out to lunch with friends, yet she's still in the hospital.' Length of stay has nothing to do with a label and everything to do with how sick a patient is, and what treatment they are receiving in the hospital," Lamprey said.


Another issue affected length of stay, as she had learned at one point in her direct-care days. An elderly patient who underwent a leg amputation was still in the hospital 8 weeks later. Concerned that the patient would get overly dependent on the hospital staff, Lamprey asked the patient's surgeon, known for his temper, what his plans were for the patient-against the advice of her concerned colleagues. Rather than lash out at her, the physician hesitated and then explained that the patient lived on the second floor of a building with no elevator, so he did not know what to do with her. When Lamprey offered to work with social services on a solution, the physician turned into a supporter.


Committed to furthering the cause of more effective utilization management, Lamprey later joined the hospital's Professional Standards Review Organization (PSRO). PSROs were regional organizations established in 1973 by Congress to help hospitals determine medical necessity and ensure care met professional standards of quality and was occurring at the appropriate level of care.


Lamprey met Charles Jacobs, then an Associate Director with the Joint Commission on the Accreditation of Healthcare Organizations, when attending an educational seminar he gave in 1976. An attorney, Jacobs not only clearly understood the issues with the current review system, Lamprey felt he knew what is needed to occur to address them. In addition, he had the training, intelligence, and industry recognition he would need for success. A few months after Jacobs left the Joint Commission to form what would become InterQual, Lamprey joined him as one of the new organization's first employees.


Jacobs had responded to a government request for proposal for assistance in developing a quality assurance program and was awarded the project. He quickly formed a team-which first worked out of an apartment in Chicago-to execute the contract. He, Lamprey, and a physician on staff immediately began exploring the clinical norms and the definitions of "sick" by body system: respiratory, cardiac, orthopedic, reproductive, and so on. In developing the criteria, the team would always ask physicians the same question: "If you are admitting a patient with X, what would lead you to make the decision to admit?" Although physicians gave consistent answers, the InterQual team found that few followed that course, instead following the rules set forth by their organizations.


InterQual published its first severity of illness/intensity of service criteria in 1978 for evaluating appropriateness of admissions and level of service. Later, the company added discharge screens when it realized that hospitals also needed guidance in determining when patients were well enough to go home.


Considering the earlier example of an elderly woman with pneumonia, with the InterQual criteria, the strongest piece in the equation became "What treatment should the patient be receiving, and where should that care be delivered?" For pneumonia in the early days of InterQual, if the treatment was intravenous antibiotics to be administered and blood gases to be drawn every 4 hr, then the appropriate site was "an acute care setting until the patient is ready to go home." And ready to go home meant when the patient had a temperature within a normal range of 97-99[degrees] for 24 hr and was voiding, passing gas, able to ambulate without assistance, and so on.


The criteria were piloted with several state PSROs, which initially had to apply for exemptions to use InterQual over competing criteria. The more physician panels they encountered, the more confident the InterQual team grew in the rightness of their approach. Eventually, all 203 PSROs were using InterQual.



InterQual meanwhile was building a significant following for the criteria by teaching concurrent review process seminars across the country as well as by consulting with individual PSROs. Lamprey, who conducted many of the seminars, made no secret of her feelings for the early generation guidelines, and thus, her quest for a better approach: "It was all process, it was expensive, and it was embarrassing to be a nurse reviewer. I would ask nurses and physicians alike, 'Why would you assign a length of stay? Don't you want to discharge your patient when they are well? Why do we base this on numbers?'"


Entering the early 1980s, the PSROs were using InterQual but often found themselves at odds with regional Medicare staff because the federal government had not yet accepted the validity of InterQual. Ultimately, InterQual was invited to Washington, DC, along with two or three competing organizations, to present their various criteria sets and the philosophies driving their creation. A large audience assembled to hear the presentations, and the InterQual approach faired well in the critical discussions that followed, further eliminating barriers to acceptance.



Over the years, the InterQual team worked hard, constantly improving and updating the criteria, also adding criteria sets as they identified the need. Consulting became a growing part of the business, and InterQual was always sure to involve the most reluctant/skeptical physicians in the process of getting programs to work efficiently. Once physicians understood that the InterQual team was not there to second guess them but instead to communicate on a clinical level about what was best for patients, resistance was replaced with acceptance. When DRG-based reimbursement arrived on the scene in the mid-1980s, hospital administrators also began to understand the criteria's ability to affect their organizations' bottom line (see sidebar 1).


Today, the fundamental philosophy of the criteria and the commitment to innovation have remained the same. More than 60 clinical professionals at McKesson, including physicians, registered nurses, and allied healthcare professionals, are involved in developing clinical content, which is then reviewed and validated by a nationwide network of more than 800 practicing clinicians from academic and community-based settings covering all major specialties. Used by healthcare providers as well as payors, InterQual often serves as a standard lexicon when it comes to decisions about the appropriateness and quality of care (see sidebar 2). Evidence-based and impartial, these criteria also support integrated care management approaches.


Now, in electronic format, InterQual criteria can be accessed from within care management workflow software or via the Internet, which supports greater efficiency, consistency, and communication among patients' care teams. Physicians who want to better understand the criteria being used during the review process have an open window plus the ability to drill into the medical literature for more information. Moreover, organizations have the ability to create new criteria or customize existing criteria to meet specialized needs.



The history of InterQual continues to be written, but what it has achieved in its 30-year history is a remarkable reminder to everyone working in healthcare today that even a few dedicated individuals can transform the industry for the better. All it takes is a willingness to challenge an existing practice with a better idea and the persistence to convince the industry to listen.


SIDEBAR 1 The Development of InterQual

Late 1970s: InterQual, Inc., is founded, and the company publishes the first severity of illness/intensity of service (SI/IS) criteria for acute care, making practical review of the appropriateness of hospitalization possible.


1980s: InterQual adds criteria for helping determine appropriate hospital discharge planning as well as pediatric criteria. A product is launched to provide tissue committees with a tool for retroactive monitoring of surgery and procedures.


1990s: Criteria are released for surgery, invasive procedures, imaging, and workers' compensation, as are tools to assist decision-making in rehabilitation, subacute, skilled nursing, and home care settings. Software for accessing the criteria is introduced. The Health Care Financing Administration (now the Centers for Medicare & Medicaid Services) licenses InterQual criteria for use in reviewing Medicare hospital inpatient services.


Early 2000s: Behavioral health, durable medical equipment, long-term acute care, outpatient rehabilitation, and chiropractic criteria are introduced and expanded. Disability case management content is added. New formats for facilitating the criteria's use and understanding are introduced, most notably CareEnhance Review Manager, which provides browser-based access to the criteria and streamlines clinical reviews. URAC certifies CareEnhance Review Manager, marking the first time this quality standards organization certifies a software solution.


Mid-2000s: CareEnhance Review Manager adds support for denials management and discharge planning, and powerful integration capabilities. Criteria for several controversial procedures and imaging studies are introduced and workers' compensation and disability management products expanded. The InterQual clinical content development team undergoes rigorous training with the Delfini Group, a world-renowned consulting firm in evidence-based medicine.


SIDEBAR 2 Case Study

Case #1: Chest Pain and Determining Observation Versus Inpatient Status


Chest Pain


Rhonda, a 56-year-old woman, with left-sided chest pain presented to the emergency department (ED). She reported experiencing the pain for 20 min with radiation to her left arm. She received nitroglycerin /3 SL and intravenous morphine sulphate /1 without relief. Intravenous nitroglycerin drip was initiated at 5 &;g/min and titrated up to control the pain. O2 at 3 L/min per NC was started. The patient stated she had no significant medical problems and was not taking any medications. This patient met inpatient criteria.


Physical examination


Bilateral basilar crackles noted




Blood pressure (BP) 88/50 mmHg


Heart rate (HR) 110 beats per minute and regular


Respiratory rate (RR) 16 per minute


Electrocardiographic (ECG) changes with ST elevation consistent with an anterior myocardial infarction (MI)


CXR shows mild heart failure


BS 212


Na 134


K 4.0


O2 saturated at 90% with supplemental oxygen



Physician orders


Vital signs (VS) q 1h


Repeat enzymes and ECG per protocol


Intravenous nitroglycerin: titrate until pain resolved; maintain systolic BP > 100 mmHg


Intravenous heparin 5,000 unit bolus then 1,000 units/hr continuous drip


Furosemide (Lasix) 20 mg iv /1


Cardiac catheter scheduled for today


Monitor I & O q1h


Cardiology consult


O2 via 3L nasal cannula



Case #2: Chest Pain Observation Versus Inpatient Status


Olivia, a 59-year-old woman who was on her way to work, experienced left-sided chest pain and is now presenting to the ED. She reported having pain for 15 min that radiated down her left arm. In the ED, she received aspirin, nitroglycerin SL, and morphine /1 with relief of her symptoms. Her husband has been contacted and is on the way to the hospital. This patient should be considered for observation status.




BP 130/72 mmHg


HR 100 beats per minute


RR 16 per minute


ECG normal


CXR normal


Troponin T and Troponin I negative (less than 0.1)


Creatine kinase-MB < 0.5


BS level 198 mg/dL


Na 142


K 3.0


O2 saturated at 92% on room air



Physician orders


Admit as observation for cardiac monitoring (telemetry floor)


Place on R/O MI protocol (rhythm strips, serial cardiac markers [CK, troponin], and ECGs)


VS q2h


ECG if chest pain reoccurs per chest pain protocol


Schedule stress test, if enzymes negative


Continue preadmit medications