Evidence-based medicine (EBM) is the conscientious, explicit and judicious use of current best evidence in making clinical decisions about the care of individual patients.10–12 However, non-clinical influences on decision-making may be the most important, and up to now largely unrecognized obstacle to the practice of EBM.
Literature search strategy
Articles were identified by FMH using Google Scholar, EMBASE, CINAHL and PubMed, and the Cardiff University School of Medicine medical library. The key search words and phrases were: clinical decision-making, influences on clinical decision-making, non-clinical influences on clinical decision-making, influences on patient management decisions, factors influencing clinical decision-making, barriers to healthcare access, and influences on prescribing decisions.
Patient-related factors
The patient's socioeconomic status
A patient's socioeconomic status can influence management decisions. In the USA, being aware that patients have a low socioeconomic status often influences primary care physicians to change their management plan to suit those with financial difficulties.9 The influence of socioeconomic status could lead to patients receiving less than ideal or non-standard treatment, for example less aggressive diabetes management or postponement of biomedical tests.9 However, in other healthcare systems, e.g. the UK where there is free healthcare, this influence may not be so relevant. Moreover, the sample size of 18 physicians in this study9 was small and there was no consensus among the physicians on the definition of low socioeconomic status and on the role of this status on clinical decision-making.
In Canada, patients with a low income visit specialists at a lower rate than those with a high income despite the existence of a free universal health system.13 Also in Canada, acne patients with low socioeconomic status were less likely to visit dermatologists.14 This may be because patients with lower income may face other financial or time difficulties which may limit their visiting specialists, for example difficulties in transportation and travel expenses15 or time commitment at work or with children.16 A limitation of the acne study14 was that it did not record acne severity; only socioeconomic status and rural versus urban influences were studied, and these may not be the only reasons for referral to dermatologists.
The cost of care and the patient's ability to pay may influence the physician's therapeutic plan. Patients with a high socioeconomic status who are able to pay for healthcare are more likely to have medical tests than patients with a low socioeconomic status.17 Physicians may change their prescription strategy, shifting to a cheaper drug within a therapeutic class or shifting to another drug covered by the insurance scheme.18 Even among insured patients there may be some with insurance plans giving only limited coverage.18,19 This socioeconomic status disparity may reduce the quality of patient care and result in undesirable consequences. For example, in the USA insured patients are able to receive better primary care than uninsured patients, and privately insured patients are able to receive better primary care than the publicly insured.19 Uninsured patients who were paying for their medication were less likely to adhere to treatment.20,21 Compared with the insured, patients without health insurance receive fewer inpatient and outpatient services,22 undergo fewer cancer screening tests and have different overall treatment patterns.22,23 If they have breast cancer, they are less likely than insured patients to receive appropriate screening and diagnostic workup and to obtain treatment consistent with current standards of care.24,25 The decision to recommend mammography was strongly associated with socioeconomic status and age but not with ethnicity.25 Uninsured patients were more likely to be diagnosed with late stage cancer,26 have a higher mortality rate from breast cancer,23 and have a lower three-year survival rate from colorectal and lung cancer22 compared to insured patients. This may reflect the delay from patients in seeking medical help because of the assumed potential financial burden.
The patient's race
The influence of a patient's race on clinical decision-making has been studied in the USA and South Africa. In the USA,27 whites were more likely to receive zidovudine (AZT) treatment for HIV infection than non-whites. One explanation is that physicians (of whatever race) are aware that HIV treatment needs strict adherence to medication and assume that black patients adhere less to treatment than white patients. Blacks, compared to whites, receive less coronary artery bypass surgery28 and less invasive cardiovascular procedures.29 In South Africa, black women receive fewer Caesarean operations than white women,30 though arguably the lower Caesarean section rate may be preferable. In one UK study,31 psychiatrists were asked to read and diagnose a case history describing an agitated patient with paranoid delusion whose family reported that they suspected the patient had been smoking cannabis. If the patient was described as Afro-Caribbean, the diagnosis was more likely to be cannabis psychosis, whereas if the patient was described as white, the diagnosis was more likely to be schizophrenia. However, the results from these hypothetical scenarios may not reflect real-life cases, and there is the possibility of bias due to under-reporting of psychiatric symptoms, such as depression, by African-Americans.31
‘Do not resuscitate’ (DNR) orders in the USA32 were more commonly applied to black people, alcoholics, non-English speakers, and to people infected with HIV, highlighting how non-medical information may influence a critical medical decision.32,33 However, the former study32 did not determine whether these differences were due to patients' preferences or to physicians' characteristics. However, black patients have been found to be more likely than white patients to prefer cardiopulmonary resuscitation (CPR) over having a DNR order applied.34 Black patients were also found to be more likely than white patients to want to discuss the CPR order with their physicians, even though they were less likely to have this type of discussion.34 This may explain why the use of DNR orders was substantially lower in African-American patients than in white patients.35
Patient's race may influence physicians' recognition and treatment of depression.36 African-Americans were less likely to be treated with antidepressant medications compared to white patients with similar levels of symptoms of depression.36 Several causes of this disparity have been suggested, including black patients feeling stigmatized by a mental health disorder, low patient education and recognition of depressive symptoms, inability of black patients to access and pay for treatment, and inability of physicians to recognize symptoms of depression in a minority group.36
African-Americans with renal cell carcinoma were less likely than whites to be treated with Interleukin 2, after controlling for age, tumour grade, co-morbidities and other relevant clinical variables.37 Various reasons were suggested, including limited financial resources for African-Americans, and living in rural areas with reduced access to specialized centres. Awareness of side-effects of Interleukin 2 and the necessity of frequent hospitalization might deter this group of patients from having this treatment. Younger individuals were under-represented in the study and the findings were only applicable to older patients with metastatic renal carcinoma.
In some countries, therefore, if a patient is of Afro-Caribbean origin or from another ethnic minority, this may inappropriately influence their management decisions.