Discussion

Are patients a reliable source of reports of adverse events?

The people surveyed across different countries describe a high occurrence of adverse events4 6 9 11 20 with negative consequences,4 6 20 although rates tend to decrease as the inquired period was shorter. Despite their variability, mostly due to the plurality of the definitions of adverse events, the figures were consistent when compared to those obtained through other procedures. Thus, the percentage of adverse events (7%) found by Evans et al4 is within the range obtained via medical record review (2.9% to 16.6%).23 In turn, the frequency of adverse events (50.6%) referred by patients in the study conducted by Agoritsas et al12 is closer to the cumulated incidence of adverse events (46%) noted through observational methods, rather than by reviewing of medical records.

While some authors consider patient reporting trustworthy, others seem to be skeptical. For instance, Agoritsas et al12 conclude that reports of adverse events by patients may be a valuable indicator of quality and safety, since they are not constrained by local regulations and the culture of safety as professionals are. However, in the study conducted by Blendon et al,19 an overwhelming majority of the public (68%) did not know the meaning of adverse events. Also, the patients' concept of adverse events differs from that of clinicians. For instance, in the study by Gallagher et al,17 patients included some non-preventable adverse events as medical errors.

To avoid information biases, some authors opted to explore the patients' concept of adverse events through a preliminary survey.17–19 Other times, they gave a definition of adverse events,6 11 17 20 21 or a list of possible adverse events.9 12 13 Also, as some authors noted,6 11 the close-ended questions may hinder to clarify the patients' responses and are usually elaborated from the professionals' or administrators' perspective. Thus, open-ended questions and less structured interviews are required to deepen in patients' perception of adverse events. In addition, since adverse events are emotionally charged and open to multiple interpretations, Vanderheyden et al6 suggest to add a cognitive test in the pretest phase and to include emotional and social consequences as fixed responses in the survey.

Clearly, exploring patients' perspective has allowed to broaden the concept of adverse events. Patients emphasised psychological trauma and social, laboural and economic troubles as the most important consequences of adverse events, rather than death, physical harm, readmission or delayed stay in hospital, from the typical physician and manager viewpoints.

Regarding the limitations of the studies, there was a high variability related to the sample size, and response rate was usually below 60%.6 7 9 15 19 In slightly over a half of the survey studies, validated questionnaires were used.6 7 12–14 20 However, there was no independent verification of adverse events referred (or silenced) by patients in order to guarantee confidentiality. Also, external validity is jeopardised in the studies sampling from specific populations. Few studies fight the ethnocentric trend that hides migrant population, which present special vulnerability not only due to language but also to cultural barriers. On the other hand, in the study by Adams and Boscarino,9 belonging to wealthier households was associated with a lower likelihood of suffering adverse events, as compared to respondents from poorer households. Also, female sex is associated to higher reports of adverse events,6 and in the study by Daniel et al,10 70% of the complainers were women. Therefore, although every consumer is at risk of suffering an adverse event during healthcare, it seems that there are specific social groups more likely to suffer one. Further research should target the adverse events experienced by the most vulnerable social groups through positive discriminatory approaches.

Prospective research aimed at identifying adverse events should use observational methodologies to provide a more realistic sight. For instance, ethnographic method is useful to detect adverse events during healthcare praxis and facilitates to analyse adverse events inside their natural context. Also, it offers a relational perspective beyond unilateral point of view. This approach targets the patient–provider interaction, the bedrock of patients' perception of care safety highlighted across the reviewed studies. In addition, causal analysis of adverse events may be addressed through longitudinal and experimental studies, as some authors suggest.5 9

Do patients feel safe in hospitals?

Clearly, patients seem not to be particularly concerned about clinical safety and usually are not aware that extended hospital stays or treatment and readmission are risk factors for adverse events. Thus, less than a half of them (25% to 40%) are referred having felt some degree of concern at some point.4 13 22 However, perception of safety changes when they or a householder experience an adverse event, especially as its severity grows.4 Furthermore, having suffered an adverse event has a great impact on the patient's trust in physicians and hospitals, with potential consequences on follow-up and treatment adherence. Therefore, physicians should identify these patients and implement individualised strategies in order to reduce those concerns.4

A premise of the Alliance for Patient Safety is to recognise the magnitude of the problem by physicians and patients in order to reduce the frequency of adverse events and their consequences. Most people, including health professionals, underestimate the frequency of adverse events and preventable deaths in hospitals. Nevertheless, presenting such figures as an indicator of perception of safety may not be the best way to ask about adverse events and people's awareness. Peters et al5 state that while experts' concept of risk is related to technical estimations of deaths, for patients, it is mostly associated with less rational aspects, as loss of control and feelings of fear or threats.

Usually, patients who felt concerned in hospital were worried about a particular potential error rather than multiple errors. This fact suggests that patients adapted to environmental clues they associate with potential errors.13 In this sense, patients' concern can be understood as a state of alertness for preventing adverse events,5 although other authors consider that this vigilance may increase patients' anxiety, and they may find it difficult to warn professionals of potential errors.13

What do patients opine about disclosure of adverse events?

Physician–patient communication stands out as the key to prevent and manage adverse events. The majority of the patients wanted physicians' disclosure to the error; they want to be informed immediately of what happened and how it happened, the causes and the consequences, as well how the adverse events could be mitigated and prevented,3 7 8 15 17 21 specially as the severity of the error increased.15 Moreover, patients, particularly those who are victims of adverse events and have raised complaints complaints, expect to receive an apology, rather than financial compensation, from the physician, emotional support, as well as assurance that institutional efforts will be made to prevent such errors from happening again, and eventually regain trust in the health care professionals.14 17 Nevertheless, most of the studies addressing this topic presented series of case scenarios, whereby the expressed opinions may differ from those of real victims.

It is worth to note that despite the fact that physicians endorse adverse events disclosure, only one-third of patients who were victims of a medical error received an explanation or an apology from their physician.19 Many physicians feel it is not their task to report the error, and they avoid to inform how it happened for fear of being held responsible3 or sued.17 However, most injured patients were angrier at the way they were treated than at the error itself; they regarded physicians' cold attitudes as a way of neglecting what happened or that they were hiding the truth.8 The likelihood of filing legal complaints regarding surgical errors was linked to poor explanations from the physician.14 Also, non-disclosure of adverse events, a delayed response or a serious harm, regardless of the cause, was associated to lack of safety perception by the patients and no recommendation of the hospital.7 12 Contrariwise, a good patient–provider communication influences the patient's interpretation of the error as a human error, increases patient perception of physician competence, reduces emotional trauma and leads patients to keep their relationship with the physician.8 16

What do patients suggest to prevent adverse events?

Patients agreed that adverse events were related to management of healthcare. More specifically, besides timeliness and professionals' overwork, most of the patients underscored failure of team coordination as a main cause of adverse events.

Patients endorse measures to address safety, such as systems of reporting adverse events to a state agency, not only to learn how to prevent future mistakes but also to inform the public. Physicians are more sceptical about these proposals, mainly due to fear of malpractice litigation.19 20

Usually, patients lay responsibility on the professionals rather than institutions,6 especially when the consequences of an adverse event are serious and support legal complain. On the other hand, although professionals consider that adverse events are sometimes caused by system failures,3 6 20 they usually attribute responsibility to themselves,19 find it difficult to discern negligent errors from unintended errors19 and emphasise individual blame rather than collective responsibility.3 Both patients' and physicians' beliefs call for intervention to build culture of healthcare safety. The most effective strategy to improve safety is to target those adverse events due to system failures, rather than blaming individual health professionals. Nevertheless, these substantial changes must be accompanied by reforms of medical legislation.