Kaoru Ishikawa Fishbone Cause-Effect Diagram and Benefits for Healthcare – Healthcare Market Overview

To advance the quality level of a healthcare organization, all healthcare staff must “require” continuous quality improvement and be on an equal footing with industry-standard healthcare quality competencies. From a health management perspective, this starts with training (Knowles, 2019). The National Association for Healthcare Quality (NAHQ) has created a framework of 486 behavioral-based competencies across 29 core competencies and 8 dimensions, which outlines key workforce competencies for quality-driven healthcare within an organization. NAHQ recommends that healthcare organizations “link” this industry-standard healthcare quality competency framework into everyday healthcare quality practices, increase training and education to improve performance, and focus on workforce development (NAHQ, 2019). However, the NAHQ end-to-end quality training method is not an original concept. Kaoru Ishikawa, considered by many to be the “father of Japanese quality control”, believed in the value of extending quality training to all levels of the organization and supporting the Companywide Quality Control (CWQC) strategy (Kaoru Ishikawa, 1985). More specifically, Ishikawa developed a visual tool for determining the root causes of certain low-quality events, known as “Ishikawa diagrams,” in 1982 (Kaoru Ishikawa, 1976). His quality management techniques and innovations have revolutionized industrial processes in the manufacturing industry, and healthcare organizations may find it necessary to understand how his philosophy can be applied to improve healthcare quality. Adequate analysis of Kaoru Ishikawa requires an in-depth investigation of his background, his contribution to quality improvement, and the potential benefits of his philosophy for healthcare.

Although Ishikawa’s quality management techniques and innovations have had a lasting impact on modern quality control, his young and professional background played an important role in the development of his quality management philosophy. Kaoru Ishikawa was born on July 13, 1915 in Tokyo, Japan as the eldest of eight children of Ichiro Ishikawa. The future expert and father of Japanese quality control received an engineering degree in applied chemistry from the University of Tokyo in 1937. After graduation, Ishikawa found employment as a Naval Technical Officer and led over 600 construction workers in the development of a factory. He noted how invaluable this experience was to his career as a quality specialist. In 1941, Ishikawa joined the Nissan Liquid Fuel Company, working in the coal liquefaction. This is where Ishikawa cut his teeth in research, design, construction, and operations (ASQ, 2019; Best & Neuhauser, 2008; Hessing, 2018). By 1947, Ishikawa had started the academic path as a professor and researcher at the University of Tokyo, his alma mater. As an academic, Ishikawa began studying statistical methods. In 1949, Ishikawa joined the quality control research group of the Union of Japanese Scientists and Engineers (JUSE) as an instructor. It was through this experience that he first became acquainted with the Total Quality Management (TQM) system after translating and developing the concept of two quality management experts, W. Edwards Deming and Joseph M. Juran, and incorporating their innovative quality concept into the Japanese concept. quality improvement system. Ishikawa is Chief Executive Director of Quality Control Circle Headquarters at JUSE, and editor of two books produced by JUSE on quality circles, entitled “QC Circle Koryo” and “How to Operate QC Circle Activities.” In 1960, Kaoru Ishikawa was promoted to Professor, and he received his doctor of philosophy (PhD) in engineering from the Musashi Institute of Technology that same year. In 1978, he was appointed President of the Musashi Institute of Technology at Tokyo City University. Ishikawa taught his quality management philosophy to executives and top managers through quality control courses in the late 1950s and early 1960s, and he continued to share his knowledge through various publications until his death on April 16, 1989 (ASQ, 2019; Hessing, 2018).

Although Ishikawa made many contributions to quality improvement, he is perhaps best known for his “Fishbone Cause-Effect Diagram”. A fishbone causal diagram, colloquially known as an “Ishikawa diagram,” is a visual causal diagram for performing root cause analysis (Kaoru Ishikawa, 1976). Root cause analysis is a problem solving method that “[identifies] the real reason that the problem or undesired condition occurred” (Wilson, Dell, & Anderson, 1993). The Ishikawa fishbone diagram is most often used to identify causal factors during product design and quality defect prevention. A fishbone diagram is a “highly visual brainstorming tool”, which generates root causes, recognizes whether a root cause appears repeatedly in the same or different cause trees, allows for simultaneous viewing of all causes, and enables a mechanism to present complications to companies and companies. . organizational stakeholders; however, diagrams can be “visually cluttered” when a complex problem results in multiple root causes. Also, the linkages between root causes are not easily identified on the fishbone diagram (Firican, 2018). Ishikawa is also known for implementing the “Quality Circle”. A quality circle (QC) is a collection of 3 – 12 workers who complete similar tasks and meet frequently on their own time to identify, analyze, and solve work-related problems. QC members require training in group dynamics, problem solving techniques, and report presentation as well as using a basic methods study approach to problem solving by asking who, what, why, when, where, and how (Basu & Wright, 2003). QC has the ability to “increase productivity and improve quality,” and the seven QC tools, as identified by Ishikawa, include: (1) Pareto chart, (2) cause-and-effect chart, (3) Stratification, (4) Check sheet, (5) Histograms, (6) Scatter diagrams, and (7) Graphs and control charts. As previously mentioned, Ishikawa is a champion in Whole-Company Quality Control (CWQC) activities. CWQC is characterized by the involvement of all sectors of the company and all employees, “from top management to line workers and salespeople,” and “integrated process control” (K. Ishikawa, 1984; Peterson & Barker, 1992). Ishikawa also emphasizes “internal customers”. Internal customers, as opposed to external customers, are customers who have a direct stake in the “operation and success” of an organization, and often include stakeholders, employees and shareholders. Internal customers do not influence the company’s strategy and operations, but have a direct impact on the success of the organization. Ishikawa also believes that to be successful, an organization must be alert to both internal and external customer satisfaction (Tennant, 2001). Through these contributions and innovations, Kaoru Ishikawa was able to transform Japan’s post-World War II economy and advance our understanding of quality management and quality improvement, which ultimately spawned business success.

While Fishbone Cause-and-Effect Diagrams, Quality Circles, Company-wide Quality Control strategies, and Ishikawa’s “Internal Customer” philosophy have left a huge mark on the analysis of industrial processes in manufacturing, his philosophies have also had beneficial effects in healthcare. . Several hospital services in Germany—ranging from pediatric diabetes care to trauma and gastroenterology—have begun using Ishikawa’s “Circle of Quality” to improve patient outcomes (Heldwein, Birkner, Strauch, & Konig, 1996; Holl & Grabert, 2002; Juhra & Raschke, 2013). Reilly et al. reported how Ishikawa’s fishbone diagram has helped clinicians analyze diagnostic errors in Internal Medicine (Reilly, Myers, Salvador, & Trowbridge, 2014). And, Lyra et al. used the Ishikawa fishbone diagram to isolate the cause of diffuse flat keratitis (DLK) outbreaks in their healthcare facility (Lira, Hirai, Oliveira, Portellinha, & Nakano, 2017). Kaoru Ishikawa’s quality management philosophy offers endless applications across a wide range of industries, and his contributions continue to assist organizations, including healthcare organizations, in quality improvement at all levels and in all aspects.


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