The challenges outlined above represent quality-improvement opportunities in the symptoms to diagnosis phase. Donabedian's (19
) structure–process–outcomes paradigm () may be used to organize and explore what is already known about the primary care provider–specialist interface at this phase of care and to identify where opportunities might lie. In this model, structure refers to having the equipment, resources, and provider experience necessary to provide care. Process refers to the examination of the technical and interpersonal elements of care that transpire between the clinician and patient, such as the extent of the history and physical examination, use of tests, and treatments received. The outcomes include complications, survival, and patient-reported outcomes, such as health-related quality of life (20
). Below, we elaborate on this paradigm in the context of the symptoms to diagnosis phase of cancer.
Application of the structure–process–outcomes paradigm to the symptom to diagnosis interval
Structure includes aspects of health-care systems that are of major interest to policy makers across the cancer control continuum. First, the health-care system's financial structure may have implications on access, costs, patterns of care, and outcomes (21
). In the United Kingdom, the simplicity of a single-payer system has been credited with helping to organize quality-improvement activities resulting in quality gains at the primary care level (22
). However, comparisons of managed care and fee-for-service plans in the United States have not shown, on average, significant differences in the cancer stage at presentation or patterns of care for colorectal, breast, and prostate cancers (21
). Pay-for-performance approaches did not result in quality gains in the United Kingdom, perhaps a ceiling effect, because of their previous other quality performance activities (22
) but are being promoted as possible methods of improving quality within primary care in the United States (26
). Second, information technology is an important aspect of the structure. As reviewed by Shekelle et al. (27
), information technology has the potential to transform health care, making it safer, more effective, and more efficient. However, widespread implementation has been limited by a lack of generalizable knowledge about what types of information technology and implementation methods will both improve care and also manage costs for specific health systems. As suggested by Hesse et al. in this supplement (28
), information technology alone will not be able to solve the challenges in the interface between primary care and specialists but can enhance in the retrieval of relevant information, communication between providers and/or patients, and monitor for the resolution of the evaluation process.
More specific to the symptoms to diagnosis phase of cancer care, structure includes having sufficient physicians with the appropriate training and/or experience as well as sufficient diagnostic equipment in place to perform the appropriate tests within the benchmarked time. Delays in diagnosis often occur because of physician misdiagnosis (29
), and, thus, educational interventions to improve the recognition of symptoms or interpretation of reports by physicians may be required. The appropriateness, training, and use of different diagnostic procedures in primary care, including fine needle aspiration, sigmoidoscopy, endometrial biopsy, and even dermatoscopy for skin lesions, have been published (30
), but research into the need, training, and competency testing of these skills may need to be better defined. Specialized diagnostic centers have been created, particularly for patients with breast and prostate problems, yet despite their proliferation, little information is available on how they improve process measures, cost-effectiveness, or patient satisfaction (34
We have outlined several process issues in that are addressed below. First, process issues in the model of Donabedian would include appropriate evaluation and testing of symptoms that might be related to an underlying malignancy. One potential approach to improve the evaluation process is to implement diagnostic practice guidelines. Many guidelines exist to assist clinicians how to evaluate symptoms, who should be tested, and what tests to order (38
). Conceptual tools for development of new guidelines (45
) and processes to achieve consensus on guidelines have been described (46
). Guidelines have been shown to improve structure and processes of care, but with much more modest effects on patient outcomes (48
). Monitoring for adherence with guidelines and subsequent improvements in the desired outcomes is needed (50
). It is important to note that the same guideline may not work in different health-care settings (13
); thus, success requires careful planning, implementation, and evaluation within a given system (55
Another process issue noted in is appropriate and timely communication between primary care providers and specialists. Primary care providers share anecdotal accounts of referring patients to specialists, who then evaluate, perform procedures, and make additional referrals but neglect to communicate with the referring physician. Often, the patients are left to update the primary care providers with the details of the evaluation process (56
). Consult letters often omit relating important information to the primary care provider, and referral letters from the specialist are equally deficient (57
). Primary care providers have reported that written communication is inadequate for the complexity of cancer care and would prefer face-to-face or telephone communication (58
). A Cochrane review of intervention studies found gaps in this area of research but concluded that distributing guidelines with standard forms for referrals combined with involving specialists in education would be most likely to improve the overall referral process (59
). Another systematic review found that educational materials aimed at health-care providers alone may have a modest effect on process outcomes, but not on patient outcomes, and that information about how to optimize educational materials is insufficient (60
). Gagliardi (61
) found that primary care physicians are receptive to educational interventions attached to consult letters; however, this is probably not commonly done in clinical settings. Furthermore, the use of standardized letters has been found to be useful (62
). Communication between the specialists and the primary care providers is crucial in relaying the evaluation process and whether the process has led to a definitive diagnosis, a resolution of the problem, or need for additional evaluation. Gaps in relaying this information may lead not only to suboptimal care but also in delays in diagnosis and possible litigation.
Communication between providers as well as with patients is important in the interval between symptoms to diagnosis phase (). It is critical that patients understand the goal of the evaluation and the implications of not completing the diagnostic process. Health literacy needs to be taken into account when communicating with patients (63
We're talking about a “triangle of communication” between the primary care provider, the cancer specialists, and the patients. How can we eliminate this triangle by having a single point of common information and communication?
From a Supplement Author
Understanding the financial restrictions and insurance limitations, particularly in the US health-care system, cannot be underestimated when evaluating a patient for a possible cancer diagnosis and advising diagnostic evaluation. Such evaluation is often costly and time-consuming, requiring even insured patients to pay co-pays and miss work days. Lack of insurance has been cited as a barrier to early diagnosis of cancer among adolescents and young adults (64
Reaching a timely diagnosis is another process measure that needs to be considered. In this phase of care, the patient often contributes to the delay (29
). To reduce waiting times, several studies have suggested the implementation of a facilitated referral process or one-stop investigation clinics (65
). Although minimizing delays in diagnosis is often desired, the objectives of timely diagnosis need to be clear. Most patients and many physicians believe that delays in diagnosis will result in worse cancer survival outcomes; however, a systematic review found incomplete evidence regarding the impact on cancer-related mortality of waiting for surgery (68
). Of the 27 studies found that could address the question, “Do delays in surgery of greater than 12 weeks affect survival?”, the answer was “No” in 21 (78%). Extrapolating this information to diagnostic delay, it is unlikely that the relatively small improvements that could possibly be made in reducing waiting times from presentation to diagnosis would result in measurable improvements in cancer mortality. A greater challenge, but perhaps a greater potential in changing mortality outcomes, could come from improvements in patient delay in presenting to the clinical setting for their initial evaluation.
Improvements in diagnostic delay, however, may have impact on psychological morbidity outcomes. Few studies have assessed this outcome with established quality of life tools, although several have reported the effects of waiting on patient dissatisfaction and distress (68
). Interestingly, there was a much stronger correlation between waiting time from diagnosis to surgery and satisfaction (72
). Efforts by primary care physicians and specialists working together to reduce diagnostic delays are important, but probably more so for patient psychosocial well-being and satisfaction with the health-care system than with medical outcomes.
Other factors, such as system costs and/or burden, also need to be taken into account when trying to reduce delays in diagnosis. Thus, an important challenge for multiple stakeholders within a health-care system, including primary care providers, specialists, and patients, is to agree upon an appropriate wait time, given all of the considerations. In 1999, in response to outcries for timely evaluation of breast symptoms, the United Kingdom put into place a 2-week referral rule to reduce diagnostic delays. The rule stipulated that patients who presented to their primary care providers with breast-related “alarm” symptoms are expeditiously referred to a breast clinic within a 2-week period of time; those presenting with other breast-related symptoms were advised to be fully evaluated by their primary care providers or referred for nonurgent consultation. Potter et al. (73
) found that since the imposition of this rule, the number of 2-week wait referrals increased significantly but the routine referrals remained the same, suggesting that more women were being evaluated for breast symptoms following the rule than before the rule. Interestingly, there were no differences in the rates of breast cancer diagnosis among those referred under the 2-week rule and those referred routinely, suggesting that women triaged to the expeditious referrals were not at a higher risk for breast cancer than were women who remained in the routine referral group. Finally, the authors found that the 2-week rule had an untoward effect on clinic capacity and increased waiting times for routine referrals.
The effect of the 2-week rule for referring patients suspected to have colorectal cancer was examined in a systematic review (74
) that found no difference in the rates of cancer diagnosed among patients referred expeditiously. Furthermore, the 2-week rule did not appear to identify patients at earlier stages of cancer (4
). Although the United Kingdom's “2-week rule” example did not show unequivocal success, based on this initial experience, this health system is now likely better equipped to evaluate the structure–process–outcomes and make the necessary changes.