A colleague recently sent me a link to this piece in JAMA by RS Braithwaite, MD, MS \u00a0that cautions against placing too much weight on some ‘evidence based’ decisions. When the term became popular (was it really 20 years ago) I often referred to many of its more vocal proponents as evangelists. \u00a0I still think it is often oversold. Although I realize this piece applies far more to clinical decisions than those that are population based, I have the impression that when politicians want to avoid adopting a policy they often cover themselves in this sort of jargon and false reasoning. If you think I am way off base, please comment and say so. Incidentally, the colleague was Tom Lang who replied to my note of appreciation by adding that for clinicians the three most dangerous words are “In my experience..”<\/p>\n
\u2022 There is no evidence to suggest that hospitalizing compared with not hospitalizing patients with acute shortness of breath reduces mortality.<\/p>\n<\/div>\n<\/div>\n
\u2022 There is no evidence to suggest that ambulances compared to taxis to transport people with acute GI bleeds reduces prehospital deaths.<\/p>\n<\/div>\n<\/div>\n
\u2022 There is no evidence to suggest that looking both ways before crossing a street compared to not looking both ways reduces pedestrian fatalities.<\/p>\n<\/div>\n<\/div>\n
All of these statements are clearly absurd as foundations for decision making, yet they are technically correct. In each case, these hypotheses have been untested and therefore there is no evidence to suggest otherwise, presuming a definition of \u201cevidence\u201d that requires formal hypothesis testing in an adequately powered study.1<\/a><\/sup>\u00a0Indeed, as of this writing, \u201cthere is no evidence to suggest\u201d appears in MEDLINE 3055 times, nearly as often as \u201cdecision analysis\u201d (3140 times), a common framework for using evidence to make decisions. My anecdotal experience suggests that \u201cthere is no evidence to suggest\u201d is a mantra for EBM practitioners, in a wide variety of settings. And it is infrequently followed by the clarifying aphorism \u201cabsence of evidence is not evidence of absence\u201d2<\/a><\/sup>\u00a0or discussions of more inclusive definitions of \u201cevidence.\u201d3<\/a><\/sup>,4<\/a><\/sup><\/p>\n<\/div>\n<\/div>\n Deciding not to intervene when \u201cthere is no evidence to suggest\u201d the favorability of an intervention makes sense from a decision analytic perspective when the act involves potential harm or large resource commitments.5<\/a><\/sup>\u00a0However, deciding to intervene when \u201cthere is no evidence to suggest\u201d also may make sense, particularly if the intervention does not involve harm or large resource commitments, and especially if benefit is suggested by subjective experience (eg, the qualitative analogue of the Bayesian prior probability).6<\/a><\/sup><\/p>\n<\/div>\n<\/div>\n Indeed, the fundamental problem with the phrase \u201cthere is no evidence to suggest\u201d is that it is ambiguous while seeming precise. For example, it does not distinguish between the vastly different evidentiary bases of US Preventive Services Task Force (USPSTF) grades I, D, or C, each of which may have distinct implications for decision making.7<\/a><\/sup>\u201c<\/sup>There is no evidence to suggest\u201d may mean \u201cthis has been proven to have no benefit\u201d (corresponding to USPSTF grade D), which has very different implications than alternative meanings for \u201cthere is no evidence to suggest\u201d such as \u201cscientific evidence is inconclusive or insufficient\u201d (corresponding to USPSTF grade I) or \u201cthis is a close call, with risks exceeding benefits for some patients but not for others\u201d (corresponding to USPSTF grade C). As a result, these six dangerous words may mask the uncertainty of experts. They even may be used to deny treatments with potential benefit, if they are interpreted as the equivalent of USPSTF grade D (\u201cthis has been proven to have no benefit\u201d) but really mean the equivalent of USPSTF grade I (\u201cscientific evidence is inconclusive or insufficient\u201d).<\/p>\n<\/div>\n<\/div>\n Beyond its ambiguity, \u201cthere is no evidence to suggest\u201d creates an artificial frame for the subsequent decision. It may signal to patients, physicians, and other stakeholders that they need to ignore intuition in favor of expertise, and to suppress their cumulative body of conscious experience and unconscious heuristics in favor of objective certainty. Suppressing intuition may be appropriate when the evidence yields robust inferences for decision making, but is inappropriate when the evidence does not yield robust inferences for decision making. Yet \u201cthere is no evidence to suggest\u201d is compatible with either scenario. Because decisions are particularly sensitive to patient preferences when the favorability of an intervention is unclear (eg, USPSTF grade C), \u201cthere is no evidence to suggest\u201d may inhibit shared decision making and may even be corrosive to patient-centered care.8<\/a><\/sup>\u00a0Indeed, it is instructive to note that most people make patient-centered decisions every day without high-quality (eg, randomized controlled trial) evidence, and these decisions are not always wrong. Furthermore, foundational papers in the EBM field make it explicitly clear that EBM was never meant to exclude information derived from experience and intuition.4<\/a><\/sup>\u00a0While some may argue that misuse of this phrase is only a symptom of not having received appropriate training in EBM, my experience with practitioners of EBM across the clinical, educational, research, and policy spectra suggests the contrary.<\/p>\n<\/div>\n<\/div>\n I suggest that academic physicians and EBM practitioners make a concerted effort to banish this phrase from their professional vocabularies. Instead, they could substitute one of the following 4 phrases, each of which has clearer implications for decision making: (1) \u201cscientific evidence is inconclusive, and we don\u2019t know what is best\u201d (corresponding to USPSTF grade I with uninformative Bayesian prior) or (2) \u201cscientific evidence is inconclusive, but my experience or other knowledge suggests \u2018X\u2019\u201d (corresponding to USPSTF grade I with informative Bayesian prior suggesting \u201cX\u201d), (3) \u201cthis has been proven to have no benefit (corresponding USPSTF grade D), or (4) \u201cthis is a close call, with risks exceeding benefits for some patients but not for others\u201d (corresponding to USPSTF grade C). Each of these four statements would lead to distinct inferences for decision making and could improve clarity of communication with patients.<\/span><\/p>\n<\/div>\n<\/div>\n