1. Introduction
The global pharmaceutical industry is vital in ensuring access to essential medications for populations worldwide. However, numerous challenges have hampered the efficient and safe distribution of pharmaceutical products, particularly in regions characterized by tropical climates and distant rural areas [
1]. Pharmaceutical products are susceptible to transport conditions and need strategic control to ensure quality during transport operations [
2,
3,
4].
After the drug is manufactured, it is exposed to an environmental temperature outside the packaging range during a particular time. After this time of exposure, the product passes the long-term stability test stage to determine whether or not the excursion practiced initially impacts its stability until the end of its shelf life [
5,
6]. This requirement is a challenge for the manufacturer, as the warranty extends to end-use after passing through controls in the supply chain. The manufacturer must choose the best product distribution strategy to avoid degradation and maintain quality [
3].
According to Klopott [
7], 25% of the losses in the drug cold chain are attributed to issues encountered during transportation. The primary cause of loss or damage in pharmaceutical transport is the breakdown or malfunction of refrigerating equipment, which accounts for over half of all claims. The emergence of pharmaceutical cold chain logistics is based on refrigeration technology and the development of specialized logistics. The transport of products such as vaccines, injectables, tinctures, oral drugs, drugs for external use, and biological products can be described as pharmaceutical cold chain logistics. However, a low-temperature environment may not be sufficient for some drugs, which must be kept in cold conditions [
8,
9].
Thermal route mapping is a tool that gathers information and analyzes it by collecting data from the actual distribution routes [
10]. Thermal mapping involves identifying the temperature range in which a pharmaceutical product must be transported and stored to maintain its efficacy and safety [
11,
12]. Companies operating in cold chain logistics protect consumers and improve security and reliability by performing real-time monitoring and implementing security management systems [
13].
Previous studies have aimed to mitigate the departure from optimum temperature during the drug cold chain. Paul et al. (2020) [
14] proposed the application of the Bayesian Belief Network (BBN) to effectively assess transportation disruption risks in supply chains, thereby assisting managers in predicting and formulating resilient strategies to address these risks. Zhou et al. [
15] found that the spatial fuzzy multi-criteria evaluation approach efficiently assesses and maps maritime transportation risks, assisting authorities in developing practical plans to enhance navigation strategies in the international cold chain distribution.
With the development of information technology (IT), there have been attempts to incorporate digital-era solutions into pharmaceutical distribution systems. Faghih-Roohi et al. [
16] proposed a group risk assessment approach for selecting pharmaceutical product shipping lanes using intuitionistic fuzzy numbers and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) built on Failure Modes and Effects Analysis (FMEA) to aggregate risk assessments from different experts and prioritize risks efficiently. At the same time, Shashi [
17] developed a model for digitalizing pharmaceutical cold chain systems using IoT Digital Enabler. IoT-based digital enablers can improve pharmaceutical cold chain systems by addressing known and unknown constraints and enhancing temperature monitoring, transport, and storage. Moreover, Yang et al. [
18] applied game theory to develop a reasonable revenue-sharing contract between medical institutions and logistics service providers to encourage decreased risk in cold chain transportation.
Another approach to minimize the risk of quality reduction is the combination of environmental sensor modules and wireless technology in transport vehicles for real-time data transmission, thus integrating the Internet of Things (IoT) and building intelligent systems for pharmaceutical logistics [
19,
20,
21]. When a product leaves the supplier and enters the cold supply chain, checking and controlling its environment becomes challenging. Even though developed technologies, such as the Internet of Things (IoT), can effectively address this issue, IoT devices are vulnerable to data manipulation. To mitigate this risk, Bapatla et al. [
22] employ IoT and blockchain technologies to effectively and steadily monitor and control the ambient parameters of cold chain shipments, thereby enhancing the reliability and safety of pharmaceuticals for consumers. However, the current literature does not provide an approach to forecast the risk in thermal mapping transport terrestrial routes.
Data mining is composed of the predictive modeling technique. Previous studies have proposed an intelligent supply chain management system for vaccine distribution using machine learning [
20]. The technique extracts implicit database information, identifying and classifying new patterns [
21,
22,
23]. The results obtained from data mining can be used in information management, information request processing, decision-making, and process control. The data contained in the databases are used to learn a particular target concept [
23,
24,
25,
26].
In predictive modeling and data analysis, three commonly employed algorithms are (1) Classification and Regression Trees (CART), (2) Naive Bayes (NB), and (3) Multilayer Perceptron (MP). These algorithms have distinct principles and procedures that make them suitable for various data types and predictive tasks. (1) CART is a decision tree algorithm for classification and regression tasks [
27]. It works by recursively splitting the data into subsets based on the values of the input features, creating a tree-like structure of decisions. The algorithm selects the best split at each node based on a criterion for classification or mean squared error for regression. The tree is built until the data is sufficiently divided or a stopping criterion is met, such as a maximum tree depth or minimum node size. The final model is easy to interpret, as it can be visualized as a tree, with branches representing decision rules and leaves representing outcomes. (2) NB is a probabilistic algorithm based on Bayes’ theorem, which calculates the probability of a class given a set of features [
28]. The “naive” assumption is that all features are conditionally independent given the class label, simplifying the probability computation. The algorithm estimates the probability distribution of the features within each class and then applies Bayes’ theorem to classify new data points based on these distributions. (3) MP is an artificial neural network consisting of multiple layers of neurons: an input layer, one or more hidden layers, and an output layer [
29]. Each neuron in a layer is connected to neurons in the subsequent layer through weighted connections. The network learns to map inputs to outputs by adjusting these weights using backpropagation, which minimizes the error between the predicted and actual outputs. MP can capture complex non-linear relationships in data and is widely used in tasks such as image recognition, speech processing, and other areas requiring deep learning models. These three algorithms offer powerful predictive modeling tools, making them suitable for different data types and applications in scientific research.
According to Pezzola and Sweet [
30], in the field of pharmaceutical regulation, most cross-national empirical studies have concentrated on intellectual property rights, often neglecting to examine the state’s capacity to regulate the pharmaceutical market and the differences in regulatory practices between countries, leading to difficulties in ensuring compliance during transport [
1,
2,
30]. On the other hand, poor infrastructure, such as unreliable road networks and inadequate storage facilities, hampers the efficient transport of pharmaceuticals, especially temperature-sensitive products [
31]. Brazil has uneven regional infrastructure development and relies heavily on trucks for freight [
32]; therefore, particular focus should be applied to the road transportation of pharmaceuticals to ensure quality at the destination [
33].
Automating risk analysis of temperature route specifications in the transport of pharmaceuticals allows temperature range at critical limits during the route to decision making. This automation can be done by applying machine learning training algorithms to classify the risk during thermal mapping routes. Therefore, the present study aimed to use the thermal mapping history of land freight transport routes to obtain a model for predicting the optimal temperature excursion. A risk assessment score was developed to predict different levels of risk in thermal mapping transport routes. Our study addresses a gap in pharmaceutical logistics by considering temperature excursion for packaging specifications on long drug distribution routes.
4. Final Remarks
We propose an assessment score to predict risk in the thermal mapping of pharmaceutical transport routes in Brazilian conditions. Similar to the present study, previous research indicates that machine learning models may reduce logistics operation costs [
2,
47,
48]. The cold chain literature typically pertains to transporting perishable products using thermal and refrigerated packaging methods, alongside logistics planning, to ensure the integrity of shipments is maintained [
4,
49,
50,
51]. Perishable products maintain chemical reactions attenuated due to low temperatures; however, delays and problems in transportation can have negative consequences [
52,
53].
Temperature route specification protocols are used for the thermal mapping of routes to ensure quality throughout the supply chain and predict risks during the transportation process [
54]. However, it is challenging in developing countries due to poor road infrastructure, mainly in rural areas. The temperature data outside the acceptance range needs electronic monitoring [
55]. This study might contribute to the automation of this risk prediction through machine learning to predict models and evaluate their performance for application in new data. Three models were tested to predict risk during thermal mapping, including CART, NB, and MP. The MP model was superior to the CART and NB algorithms because it performed better in the sensitivity metric or true positive rate, especially for intermediate classes in the risk classification task in route specification. In practice, this means that predicting risk with greater sensitivity at an intermediate level would help to avoid high-risk thermal mapping routes.
The infrastructure required to transport pharmaceuticals is a huge challenge. Violations of the cold chain may affect quality, making therapeutics harmful or ineffective. Predicting the risk of departure from optimal medication transport in developing countries requires careful consideration of each country’s unique challenges [
56].
As a logistics solution, the MP model outperformed the three models tested. The hit rates by class, mainly by higher hits in the intermediate class (moderate risk) prediction, justify a better application probability. This solution may contribute to the automatic prediction of risk during transport in thermal mapping and, consequently, optimize time and costs in the distribution of pharmaceutical products [
4,
49,
51,
52]. Solutions based on algorithms can provide opportunities to optimize the pharmaceutical supply chain’s complex processes.
The assessment score to predict risk in the thermal mapping of pharmaceutical transport routes is essential for risk management in specifying temperature routes and pharmaceutical logistics; consequently, it contributes to improving the chain. The MP model has great application potential and presents more accurate results in modeling. It ensures learning about risk management while transporting pharmaceutical products. The strategic and managerial bias, based on data analysis in machine learning, guides decision-making and manages risks during the transport routes of pharmaceutical products.
Predictive modeling leverages historical data to forecast future outcomes, assess whether the temperature of pharmaceuticals during transportation remained within specified limits, and identify and predict varying levels of risk in heat mapping along transport routes. These models are applicable in classifying the routes of various cold chain products based on tested specificity, enhancing predictive risk management analysis. These models can support more informed decision-making by considering potential future scenarios, reducing risk, and improving operational efficiency.