**1. Introduction**

Patient safety is a fundamental principle of health care derived from the Latin dictum *primum non nocere* (First do no harm) [1]. Despite common belief, this phrase was not part of the original Hippocratic Oath; it is deeply embedded in the medical profession [2, 3] and one of the pillars of the bioethical principle of nonmaleficence. Nonmaleficence, which was included in the Hippocratic Oath, is an umbrella principle under which medicine is practiced and should be applicable to all health care professions [4].

The axiom "do no harm" lies at the center of patient safety, which is defined by the World Health Organization (WHO) as "a framework of organized activities that creates cultures, processes, procedures, behaviors, technologies, and environments in health care" [5]. According to Rocco and Garrido [6], this framework represents a "conscious attempt to avoid injury to the patient caused by care […] and is the precondition for the performance of any clinical activity."

Safety is a primary concern in any activity involving risk. Safety systems originated in the aviation and nuclear industries and were introduced into medicine in the late 1950s by anesthesia practitioners facing costly insurance plans to cover liability for damages relating to anesthesia-related complications and deaths, which were frequent at the time [7]. The push for patient safety in mainstream medicine, however, began with the publication of the 2000 landmark report "To Err is Human: Building a safer health system," which brought attention to the high rates of medical errors in the US health care [8]. This report led to studies in other countries, which revealed similar findings, prompting the creation of the WHO World Alliance for Patient Safety in 2004 and the first concerted efforts to create mechanisms and systems aimed at reducing errors and improving safety.

Unsafe care remains one of the top ten causes of death and disability worldwide, with recent data suggesting that unsafe hospital-based care causes 134 million adverse events (AEs) each year and contributes to 2.6 million annual deaths in low- and middleincome countries [9]. Berner and Graber [10], in their study of overconfidence as a cause of diagnostic error in medicine, reported that 35% of physicians surveyed stated that they or a family member had experienced a medical error in the past five years. An estimated 10–15% of health care expenditure has been directly linked to patient harm [11], which on a global scale is the equivalent of US\$ 1 trillion to 2 trillion every year [9]. Similar findings have been reported in Spain [12, 13], as well as in many countries.

Early reports on safety risks in health care focused on adverse effects (AEs) results of the individual work of doctors, but they also brought to light an increasingly complex, interacting, and health care system in which AEs were caused by both doctors and other members of the health care team. The reports, however, also identified opportunities for teams to proactively work together to protect patients from preventable adverse outcomes.

As nurses work in tandem with doctors across all areas of care delivery, patient safety has steadily become an integral part of their practice. This is not the case, however, with physiotherapy. One of the reasons why patient safety is still in its early stages is the scarcity of data and resulting lack of awareness about error and safety. Combined, this impedes a culture where physiotherapists are inclined to disclose or report incidents, a practice that in medical practice has allowed their analysis and led to the implementation of preventive patient safety strategies and actions [14–17].

The objective of this chapter is to show that physiotherapy has not been integrated into the patient safety culture that is integrated into the daily activity of other branches of health sciences. The scarcity of information in the literature or the field of professional societies does not mean that physiotherapy does not have adverse effects. Lack of evidence does not mean absence, and absence does not mean evidence. The data search comes from the interest, and the interest comes from awareness of the problem. Our goal is to arouse interest in the possibility of adverse effects in physiotherapy and its study and to provide the concepts of patient safety that are applied in other professions.
