استفاده از آر اف آی دی برای مدیریت موجودی دارویی - بهینه سازی سیستم و کنترل انقباض

Motivated by a case study at a radiology practice, we analyze the incremental benefits of RFID technology over barcodes for managing pharmaceutical inventories. Unlike barcode technology, RFID enables accurate real-time visibility, which in turn enables several process improvements. We analyze the impact of automatic counting and discuss the system redesign critical to optimizing the inventory policy and eliminating shrinkage. We show that continuous review is superior to periodic review whenever accurate real-time information is available at no additional cost. We explain how RFID-enabled strategies vary with inventory parameters and provide a cost-benefit analysis for the implementation of RFID for the radiology practice.

Motivated by a case study conducted at the radiology practice of a major hospital network in Florida, we analyze the incremental benefits of RFID technology over barcodes in the context of pharmaceutical and drug inventory management. Healthcare has unique and strict guidelines for managing its drug supply chain. E-pedigree requirements and state and federal laws and regulations necessitate that information about the manufacturer, lot numbers, complete shipping information, dosage, etc., be registered in a drug's tag. These regulations seek to protect public health by reducing counterfeiting and facilitating product recalls in the drug industry. Although barcodes help increase security by permitting the tracking of drugs, they are not unique codes that can help pinpoint an item in its distribution network, and they do not have high data storage capacity to provide detailed information about an item; moreover, unless an item's barcode is scanned, its tracking records cannot be updated. Barcodes also have intrinsic scanning problems, creating inaccurate inventory records [11] and [32]. Within the broad topic of supply chain management, pharmaceutical and drug inventory management also differs from inventory management in other sectors. Drug inventory is closely scrutinized, and drugs are kept in small, locked storage cabinets after delivery. Moreover, certain pharmaceuticals and drugs are expensive and perishable. While the strict regulations on shipping and delivery increase the administrative costs of ordering, the unique item features and secure storage requirements increase holding costs. Certain drugs or items are also required in particular procedures and surgeries (e.g., contrast media to enhance the picture quality of an MRI or blood units in a surgery). Therefore, since a drug shortage can lead to low utilization of machines, doctors, and technologists or, in extreme cases, harm to a patient, stockouts can be extremely expensive. Before implementation of RFID, the radiology practice used barcode technology to monitor its inventory of contrast media vials. Most of the process was handled by a technologist who checked medical records, scanned barcodes of vials before administration, manually counted the number of vials in stock, and reordered weekly. These manual processes were creating serious operational problems: (1) exam mismatches (i.e., executing a job on the wrong patient), (2) adverse drug events (e.g., administering the wrong dosage), (3) stock and billing issues, and (4) shrinkage (e.g., content expiration caused by failure to use a previously opened vial). Unlike barcodes, RFID provides accurate real-time visibility of inventory status at the individual item level, as each item has a unique id tag and hence a corresponding unique inventory record. When inventory records are inaccurate and no real-time visibility exists (i.e., under barcode technology), organizations have to use manual counting and periodic review of items to reconcile the actual inventory on hand and the inventory record. In contrast, when inventory tracking is accurate and timely, managers can implement automatic counting and continuous review of stock levels. Moreover, being able to identify each item uniquely ensures that any change in the state of an item is automatically registered in the inventory record system (e.g., imminent expiration of a partially used drug vial). 1 An inventory manager therefore can additionally benefit from RFID by employing automatic counting, policy improvement (shifting from periodic to continuous review), and shrinkage tracking. The real life practices of RFID implementation in the healthcare industry, however, show that most appreciate only automatic counting and hence lose the potential for larger savings. Our paper shows how cost savings from policy improvement and shrinkage tracking are more important than automatic counting alone by comparing two scenarios: an inventory manager (1) employs old operational strategies and is content with only reducing the cost of counting inventory, or (2) also leverages the technology by changing the inventory control system from a Periodic Review (PR) to a Continuous Review (CR) policy and reducing shrinkage by tracking expiration. Under option (1) the current operational policy costs less, while option (2) uses Business Process Redesign (BPR) to extract the full benefit of RFID. To account for the impact of three additional benefits of RFID on inventory management, our paper proposes a model for PR that uses continuous costing to allow a correct and direct comparison between different PR policies and with CR policies. This is not possible with the traditional end-of-period costs used for PR models in the inventory literature. Using this model, we show that the attained optimal service level under shrinkage decreases. Also, assuming no shrinkage, we show analytically that the switch to continuous review (CR) from periodic review (PR) decreases the on-hand inventory, the level of backorders, and the frequency of orders and their corresponding costs, making CR the lower cost alternative. We also show that the optimal average order quantity and the review period length are concave increasing in the fixed cost of ordering for both CR and PR. We further look at the change in the ratio of inventory-related costs (the average inventory cost plus the average backorder cost) to average ordering cost with respect to the optimal average order quantity and fixed ordering cost. We found that this ratio is convex decreasing in the optimal average order quantity (review period), and the fixed ordering cost for CR (PR). Under RFID, manual counting is eliminated due to automatic counting of items, resulting in a lower fixed ordering cost. Hence, these results show that a decrease in the fixed ordering cost as a result of a switch to automatic counting for RFID (or CR) from using manual counting for barcodes (or PR) keeps the operational and economic metrics still lower for RFID (or CR) than for barcodes (or PR). Our results also show that for the optimal CR and PR, a decrease in the fixed ordering cost decreases the average ordering cost more than it does the inventory-related costs. We conduct a sensitivity analysis by varying inventory parameters to provide additional managerial insights in different operational environments. Through this analysis we also account for the benefit from shrinkage tracking numerically. We show that the percentage cost savings from RFID (without BPR) decrease with the service level (or, equivalently, the backorder cost), the mean and standard deviation of demand, the lead time, the shrinkage rate, and the cost per order placed under RFID,2 while the cost savings from employing BPR increase in all these parameters. The total cost savings from RFID combined with BPR therefore also increase in all parameters except in the cost per order placed under RFID. Hence, RFID is more attractive relative to older technologies in environments with high backorder costs (high service levels), high demand rates, high levels of uncertainty, high shrinkage rates, long lead times, and high manual counting costs. Our case study illustrates that the radiology practice saves 76% of its total inventory management costs by switching from barcodes to RFID and redesigning its business processes. About one quarter of the total savings is attributed to the reduced cost of counting inventory, while business process redesign accounts for three quarters. These significant cost savings result in an internal rate of return (IRR) of over 54% under the assumption that the technology has a life expectancy of ten years. The rest of the paper is organized as follows. Section 2 contains the literature review. In Section 3 we discuss the operational and economic problems encountered under barcode technology by our case study. We then provide our inventory models and analytical comparisons between periodic and continuous review policies in Section 4. In Section 5 we numerically analyze and quantify the impact of RFID on operational and economic aspects of a single-item (e.g., contrast media) inventory via the two options described briefly above, and in Section 6 we provide a cost-benefit analysis for RFID. Section 7 concludes and provides suggestions for future research.

Our case study of a radiology practice reveals some very important operational problems that could exist in any hospital setting. RFID technology can eliminate manual inventory processes and hence solve operational problems that exist under barcode technology. More specifically, we show that the inventory manager can benefit from RFID by leveraging automatic counting and continuous review and by tracking shrinkage actively. We analytically show that without shrinkage, the switch to continuous review achieves savings in all three inventory cost categories: inventory holding, backorder, and ordering costs. The long-run average cost of inventory therefore is always lower under continuous review than under periodic review. Moreover, since all three cost components decrease, their corresponding operational metrics, the average inventory on hand, backorder level, and order frequency, respectively, are also lower under continuous review than under periodic review. The percentage of cost saved by RFID without business process redesign (BPR) decreases in all parameters: service level, backorder cost per item per unit time, lead time, mean and standard deviation of demand, shrinkage rate, and ordering cost per order placed under RFID. The decrease occurs because the inventory policy is not optimal with respect to the new technology and shrinkage is not addressed, and as the parameters increase, these two effects become stronger. In other words, the value of BPR increases in all policy parameters. The value of RFID combined with BPR increases in all policy parameters except for cost per order under RFID. A switch to RFID therefore should always be accompanied by BPR, as it is then more likely to pay for itself in an environment with high service levels, high shortage costs, high uncertainty, high demand, long lead times, high shrinkage rates and high manual counting costs. We find that, for the radiology practice, the value of RFID combined with BPR is 75.63%, where the major part, 57.30%, is a result of business process redesign and the remaining 18.33% stems from elimination of the cost of manual counting. Hence, optimizing operational policies after implementing RFID provides the major cost savings. Clearly, a redesign of operational processes should always accompany a new technology to get the full benefits. Our cost-benefit analysis shows that hurdle rates of 5%, 10%, and 15% give highly positive net present values and the internal rate of return (IRR) of the investment in RFID and BPR is 54.06%. The RFID technology therefore is highly profitable for the radiology practice. The benefits of RFID are more pronounced every day, but there are still many concerns for RFID implementation: high installation and maintenance costs, the network effect of barcodes, technical problems (e.g., less than 100% readability), lack of industrial standards, privacy and data security issues, lack of management support, etc. [22], [28], [31] and [40]. Nevertheless, as more companies start to use the technology, the cost of implementation should decline due to economies of scale. Moreover, as common standards and regulations take hold, compatibility issues among different systems used by different companies should be resolved, and this will further facilitate adoption. Also, particular sectors such as healthcare that require tracking and monitoring of high-value items have more opportunity to reap benefits from RFID technology since costs and potential savings are relatively high in these sectors. While our research identifies and quantifies some important benefits of using RFID, there are many other areas that also require significant attention. Consider, for example, the shipping and delivery problems distributors face. These problems mostly occur because existing systems cannot detect errors in the delivery system and identify a package sent to the wrong customer, or because employees experience barcode scanning problems and thus record inaccurate information, yielding discrepancies in delivery data. When items are tagged by RFID, they can be tracked easily, and warning systems can be implemented to ensure correct shipments. Another area where RFID can be useful is manufacturing. According to a recent study (Kalorama [24]), “The approximate cost of launching a particular drug (in a period of more than 12 years) is approximately $800 million.” RFID can help reduce clinical trial times by minimizing data errors, increasing timely information, eliminating paper work, and decreasing inventory-related problems. We expect to address some of these areas and relevant issues in our future research.