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The operations research method of data envelopment analysis (DEA) shows promise for assessing radiotherapy treatment plan quality. The purpose of this paper is to consider the technical requirements for using DEA for plan assessment.

In total, 41 prostate treatment plans were retrospectively analysed using the DEA method. The authors investigate the impact of DEA weight restrictions with reference to the ability to differentiate plan performance at a level of clinical significance. Patient geometry influences plan quality and the authors compare differing approaches for managing patient geometry within the DEA method.

The input-oriented DEA method is the method of choice when performing plan analysis using the key undesirable plan metrics as the DEA inputs. When considering multiple inputs, it is necessary to constrain the DEA input weights in order to identify potential plan improvements at a level of clinical significance. All tested approaches for the consideration of patient geometry yielded consistent results.

This work is based on prostate plans and individual recommendations would therefore need to be validated for other treatment sites. Notwithstanding, the method that requires both optimised DEA weights according to clinical significance and appropriate accounting for patient geometric factors is universally applicable.

DEA can potentially be used during treatment plan development to guide the planning process or alternatively used retrospectively for treatment plan quality audit.

DEA is independent of the planning system platform and therefore has the potential to be used for multi-institutional quality audit.

To the authors’ knowledge, this is the first published examination of the optimal approach in the use of DEA for radiotherapy treatment plan assessment.

By considering a number of practical case study examples, the paper highlights some of the design methods of intelligent systems for use in optimisation and control. The paper describes tools and approaches that are used as well as the systems to which they are applied. The approaches include fuzzy logic decision making for optimal start‐up of combined cycle power plant, control and modelling within an automotive air fuel ratio application and optimisation of intensity modulated radiation therapy treatment. These diverse application areas have much in common in regard to the problem‐solving approaches; in recognition of this, generic aspects of the use of intelligent methodologies are also highlighted.

The purpose of this paper is to evaluate the dosimetric properties of N-(3-methoxypropyl) acrylamide (NMPA) polymer gel dosimeter using UV-vis spectrophotometry as a simple and low-cost method.

The gel samples have been irradiated to various doses using a medical linear accelerator with 6 MV beam energy. The optical density of un-irradiated and irradiated NMPA polymer gel dosimeters in terms of absorbance at 500 nm was investigated by UV-vis spectrophotometry.

The absorbance values of the gel samples were increased linearly with increasing dose in the dose range between 2 and 20 Gy. A remarkable improvement in the dose response was noticed after the addition of various concentrations of glycerol. The impact of dose rate, beam energy and the post-stability of the exposed gels was studied and found consistent with the previous study using nuclear magnetic resonance results (energy independent and dose rate independent, stable up to one week).

The results of the independent experimental spectrophotometry and nuclear magnetic resonance analyses indicate that the NMPA polymer gel dosimeter has good and consistent dosimetric features for radiotherapy dosimetry.

The ionizing radiation-induced polymerization of gel samples leads to a change in the absorbance of the irradiated gel samples. This study introduces the first characterization of NMPA gel dosimeter by means of UV-vis spectrophotometer.

The purpose of this paper is to develop an Internet of medical things (IoMT)-based geriatric care management system (I-GCMS), integrating IoMT and case-based reasoning (CBR) in order to deal with the global concerns of the increasing demand for elderly care service in nursing homes.

The I-GCMS is developed under the IoMT environment to collect real-time biometric data for total health monitoring. When the health of an elderly deteriorates, the CBR is used to revise and generate the customized care plan, and hence support and improve the geriatric care management (GCM) service in nursing homes.

A case study is conducted in a nursing home in Taiwan to evaluate the performance of the I-GCMS. Under the IoMT environment, the time saving in executing total health monitoring helps improve the daily operation effectiveness and efficiency. In addition, the proposed system helps leverage a proactive approach in modifying the content of a care plan in response to the change of health status of elderly.

Considering the needs for demanding and accurate healthcare services, this is the first time that IoMT and CBR technologies have been integrated in the field of GCM. This paper illustrates how to seamlessly connect various sensors to capture real-time biometric data to the I-GCMS platform for responsively supporting decision making in the care plan modification processes. With the aid of I-GCMS, the efficiency in executing the daily routine processes and the quality of healthcare services can be improved.

AUTOMATION IN THE STEEL INDUSTRY The results of the rapid expansion in the fields of Process Control and Automation since the 1960's are now being seen in industrial applications. Although these industrial applications vary, they now cover the wide range of control systems, from small single processor monitoring systems to large mutli‐processor configurations. The Steel industry provides many examples of the intelligent application of such systems, particularly in controlled instrumentation. Earlier developments in this field produced units which were simply additions of existing Analogue and Digital computers to basic spectrographic equipment for calculation purposes. Since the 1970's, however, the complete control of the Analytical instrument has been the common practice.

The purpose of this paper is to evaluate and improve the quality and the reliability of pre‐treatment quality controls of an efficient technique of radiotherapy called IMRT (intensity‐modulated radiation therapy). The aim is then to determine if the controls can be safely reduced while keeping an optimal level of quality.

The statistical process control method (SPC) was applied to quality assurance in IMRT. In order to characterize prostate and head‐and‐neck treatment process variability, individual value control charts and moving‐range control charts were established.

Control charts showed that prostate and head‐and‐neck treatment processes are only subject to random causes of variability, which means they are statistically controlled. It was proved that both processes are statistically stable and capable.

The paper shows that SPC is an efficient method to objectively determine if quality controls can be reduced.

The purpose of this paper is to propose a new dithizone solution dosimeter for high radiation applications such as polymers applications and food irradiation.

Gamma-rays cell of Co-60 source with 8.4 kGy/h dose rate was used to irradiate the dithizone solutions at different irradiation temperatures. The optical measurements of unirradiated and irradiated dithizone dye solution dosimeters were performed using a UV/VIS spectrophotometer at absorption peaks of 421 and 515 nm.

The new dosimeter improved significantly with the increase of dithizone dye concentrations from 0.025 to 0.1 mM. The dosimeter shows a perfect pre- and post-irradiation stability after irradiation for five days. Because of irradiation temperature dependence, the dithizone solution dosimeter should be corrected under actual processing conditions.

Dosimetry is a key point in quality control of radiation processing to assure that uniform and correct radiation doses are delivered to a region of interest. Therefore, this study introduces a dithizone solution dosimeter for high-dose radiation applications such as food irradiation, polymers applications and agriculture.

Ionizing radiation interacted with the ethanol solvent, resulting in the formation of free radicals, then these free radicals interacted with the dithizone molecule and changed the dye color from yellow to orange.

Treatment delays must be avoided, especially in oncology, to assure sustainable high-quality health care and increase the odds of survival. The purpose of this paper is to hypothesize that waiting times would decrease and patients and employees would benefit, when specific lean interventions are incorporated in an organizational improvement approach.

In 2013, 15 lean interventions were initiated to improve flow in a single radiotherapy institute. Process/waiting times, patient satisfaction, safety, employee satisfaction, and absenteeism were evaluated using a mixed methods methodology (2010-2014). Data from databases, surveys, and interviews were analyzed by time series analysis, χ², multi-level regression, and t-tests.

Median waiting/process times improved from 20.2 days in 2012 to 16.3 days in 2014 (p<0.001). The percentage of palliative patients for which waiting times had exceeded Dutch national norms (ten days) improved from 35 (six months in 2012: pre-intervention) to 16 percent (six months in 2013-2014: post-intervention; p<0.01), and the percentage exceeding national objectives (seven days) from 22 to 17 percent (p=0.44). For curative patients, exceeding of norms (28 days) improved from 17 (2012) to 8 percent (2013-2014: p=0.05), and for the objectives (21 days) from 18 to 10 percent (p<0.01). Reported safety incidents decreased 47 percent from 2009 to 2014, whereas safety culture, awareness, and intention to solve problems improved. Employee satisfaction improved slightly, and absenteeism decreased from 4.6 (2010) to 2.7 percent (2014; p<0.001).

Combining specific lean interventions with an organizational improvement approach improved waiting times, patient safety, employee satisfaction, and absenteeism on the short term. Continuing evaluation of effects should study the improvements sustainability.

Due to increasing complexity, modern radiotherapy techniques require comprehensive quality assurance (QA) programmes, that to date generally focus on the pre-treatment stage. The purpose of this paper is to provide a method for an individual patient treatment QA evaluation and identification of a “quality gap” for continuous quality improvement.

A statistical process control (SPC) was applied to evaluate treatment delivery using in vivo electronic portal imaging device (EPID) dosimetry. A moving range control chart was constructed to monitor the individual patient treatment performance based on a control limit generated from initial data of 90 intensity-modulated radiotherapy (IMRT) and ten volumetric-modulated arc therapy (VMAT) patient deliveries. A process capability index was used to evaluate the continuing treatment quality based on three quality classes: treatment type-specific, treatment linac-specific, and body site-specific.

The determined control limits were 62.5 and 70.0 per cent of the χ pass-rate for IMRT and VMAT deliveries, respectively. In total, 14 patients were selected for a pilot study the results of which showed that about 1 per cent of all treatments contained errors relating to unexpected anatomical changes between treatment fractions. Both rectum and pelvis cancer treatments demonstrated process capability indices were less than 1, indicating the potential for quality improvement and hence may benefit from further assessment.

The study relied on the application of in vivo EPID dosimetry for patients treated at the specific centre. Sampling patients for generating the control limits were limited to 100 patients. Whilst the quantitative results are specific to the clinical techniques and equipment used, the described method is generally applicable to IMRT and VMAT treatment QA. Whilst more work is required to determine the level of clinical significance, the authors have demonstrated the capability of the method for both treatment specific QA and continuing quality improvement.

The proposed method is a valuable tool for assessing the accuracy of treatment delivery whilst also improving treatment quality and patient safety.

Assessing in vivo EPID dosimetry with SPC can be used to improve the quality of radiation treatment for cancer patients.

Learning outcomes are as follows: students will discover the importance of process orientation in management; students will determine the root cause of the problem by applying root cause analysis technique; students will identify the failure modes, analyze their effect, score them on a scale and prioritize the corrective action to prevent the failures; students will analyze the processes and propose error-proof system/s; and students will analyze organizational culture and ethical issues.

Purpose: This case study is intended as a class-exercise, for students to discover the importance of process-orientation in management, analyze the ethical dilemma in health care and to apply quality management techniques, such as five-why, root cause analysis, failure mode and effect analysis (FMEA) and error-proofing, in the management of the health-care and service industry. Design/methodology/approach: A voluntary reporting of a case of “radiation overdose” in a hospital’s radio therapy treatment unit, which led to an ethical dilemma. Consequently, a study was conducted to establish the causes of the incident and to develop a fail-proof system, to avoid recurrence. Findings: After careful analysis of the process-flow and the root causes, 25 potential failure modes were detected and the team had assigned a risk priority number (RPN) for each potential incident, selected the top ten RPNs and developed an error-proofing system to prevent recurrence. Subsequently, the improvement process was carried out for all the 25 potential incidents and a new control mechanism was implemented. The question of ethical dilemma remained unresolved. Research limitations/implications: Ishikawa diagram, FMEA and Poka-Yoke techniques require a multi-disciplinary team with process knowledge in identifying the possible root causes for errors, potential risks and also the possible error-proofing method/s. Besides, these techniques need frank discussions and agreement among team members on the efforts for the development of action plan, implementation and control of the new processes. Practical implications: Students can take the case data to identify root cause analysis and the RPN (RPN = possibility of detection × probability of occurrence × severity), to redesign the protocols, through systematic identification of the deficiencies of the existing protocols. Further, they can recommend quality improvement projects. Faculty can navigate the case session orientation, emphasizing quality management or ethical practices, depending on the course for which the case is selected.

MBA or PG Diploma in Management – health-care management, hospital administration, operations management, services operations, total quality management (TQM) and ethics.

Teaching Notes are available for educators only.

CSS 9: Operations and Logistics.