Process reengineering methodologies have become an international management phenomenon (Waring & Bishop, 2010), as there have been a growing pressure on health services to increase their efficiency. To achieve this goal, health services have sought alternatives to traditional models, adopting methodologies for improving processes commonly used in the manufacturing sector, including lean manufacturing (Radnor et al., 2012). The lean methodology, originated at Toyota, and also known as the Toyota Production System (TPS), is considered a radical alternative to the traditional mass-production model. Lean is defined as a methodology that adopts the elimination of waste, as well as the aggregation of value to all processes, whose goal is to improve the final product (Brackett et al., 2013) and to maximize operational efficiency, quality, speed and cost of operations (Holweg, 2007). The lean approach finds popular appeal in health care as it seeks to redesign clinical practices and resources around simplified, efficient and value-added care (Waring & Bishop, 2010). The approach adopted in health systems is different from that adopted in manufacturing systems, since the processes are different, particularly for working with human lives. Thus, the definition of lean for health systems has different interpretations and practices, and is commonly called lean health care. Nelson-Peterson & Leppa (2007) state that lean health care is neither an adapted manufacturing tactic nor a cost reduction program; it is a management strategy based on process improvement in a system. Radnor et al. (2012)