## 2 Technological Advances in Point-of-Care Testing (POCT)  
### Principles of POCT  
Point-of-care testing encompasses diagnostic modalities conducted at or near the patient, aiming to deliver immediate clinical information that can inform medical decision-making. Traditionally associated with simple assays such as blood glucose measurements, the field has expanded dramatically due to advances in microfluidics, biosensors and miniaturized molecular diagnostics [17; 18]. Modern POCT platforms often combine high analytical performance with user-friendly interfaces, permitting their deployment by minimally trained personnel outside traditional laboratory environments.  
Critical characteristics of effective POCT devices include rapid turnaround time, portability, minimal sample volume requirements and connectivity features enabling data transmission to electronic health records or personal health applications [19; 20; 21; 22]. These attributes align POCT technologies closely with the needs of occupational health programs, where efficiency and accessibility are paramount.  
Cancer and chronic diseases contribute significantly to healthcare expenditure, particularly in workplace settings. A major driver of this burden is the delay between early detection and intervention, commonly resulting from the reliance on screening with laboratory tests. Over the years, various cancer and chronic disease markers have been identified, each with distinct testing technologies, including imaging tests (e.g., mammogram), biopsy tests (e.g., cervical biopsy) and biological tests (e.g., PSA blood-based test). A recent, extensive review on this subject is provided by [PERSON] and [PERSON] [8]. Laboratory pre-analytical, analytical and post-analytical errors and the transportation of biological samples to laboratories have led to significant delays between sampling and receiving test results [23]. These delays are detrimental because they compromise the effectiveness of early detection, aggravate the disease, and increase morbidity and extensive healthcare expenditure [24].  
POC and rapid testing technologies are emerging that can be deployed in workplace settings (e.g., factories, offices) to screen employees and workers for cancer and chronic diseases uniformly, inexpensively and constantly. For workplace settings, tests should ideally be low-cost, fast (single-use disposables preferred), have high specificity (>99%) and sensitivity (>90%), and provide results in <30 min (preferably 1-10 min). Diagnostic tests should saturate the entire sample size of the worker population pool to ensure that diseases are not missed. Current tests focusing on specific diseases usually overlook co-morbidity or screening for a new unrelated disease, increasing vulnerability [25]. New \"pan-catchers\" or multiplexed tests are being designed in this regard, screening different diseases in parallel using POC or rapid tests [26]. According to the World Health Organization report on workplace settings, POC testing is a priority area for making care available for all in post-COVID settings [27].  
A representative sample of the most common POCT technologies used for cancer and/or chronic disease screening is graphically presented in Figure 1.  
Figure 1: Graphical presentation of representative types of point-of-care systems used in the workplace.  
Only truly portable device categories are represented with various degrees of scale and high throughput performance. For example, paper-based diagnostic systems such as \(\upmu\)pads (with the lowest relative complexity) and lateral flow assays (self-tests, rapid tests) represent low-cost, easy-to-use, single-test modalities, the sensitivity and specificity of which may variate broadly, while digitalization of test results requires an additional step using a smartphone or other reader/recording device. On the other hand, standalone devices, including most electrochemical biosensors, can be small enough to fit into the USB port of a smartphone, offering the advantage of automated classification of test results.