preclinical Flashcards
Translational research, in the context of diagnostics, primarily aims to:
a) Publish research findings in scientific journals
b) Secure patents for new diagnostic technologies
c) Convert research discoveries into practical diagnostic tools that benefit patients
d) Conduct basic scientific research on disease mechanisms
c) Convert research discoveries into practical diagnostic tools that benefit patients. Translational research bridges the gap between scientific discoveries and their practical applications in healthcare.
Which of the following is NOT a typical application of diagnostic tests?
a) Determining the presence or absence of an infection
b) Developing new surgical techniques
c) Selecting the most appropriate treatment for a patient
d) Screening populations for asymptomatic infections
b) Developing new surgical techniques. While diagnostics may inform surgical decisions, they are not directly involved in developing surgical techniques. The other options are common applications of diagnostic tests.
The term “predicate device” refers to:
a) A new diagnostic device under development
b) An existing, approved device that a new device is compared to
c) A hypothetical ideal device used as a benchmark
d) A device used in the pre-clinical testing phase
b) An existing, approved device that a new device is compared to. When developing a new diagnostic, it must demonstrate substantial equivalence to a predicate device to ensure safety and efficacy.
During pre-clinical evaluation, the “spike and recovery” analysis is primarily used to assess:
a) The linearity of the test across the measuring range
b) Whether the test results are affected by the composition of the sample (matrix effects)
c) The ability to detect the lowest concentration of the analyte
d) The consistency of results between different operators
b) Whether the test results are affected by the composition of the sample (matrix effects). Spike and recovery analysis determines if components in the sample interfere with the accurate detection of the analyte.
In the context of diagnostic test evaluation, “accuracy” specifically refers to:
a) The ability to identify true positive cases
b) The ability of the device to produce the correct result
c) The consistency of results obtained from repeated measurements
d) The ability to distinguish between similar analytes
b) The ability of the device to produce the correct result. Accuracy reflects how closely the test results align with the true values.
Explain why a thorough evaluation of diagnostic tests is essential, particularly in light of the rapid development of new technologies.
Safe: Evaluation helps identify potential risks or harms associated with the test, protecting patients from adverse effects.
Effective: Rigorous assessment confirms that the test accurately measures what it is intended to measure and performs reliably, enabling accurate diagnosis and informed medical decisions.
Appropriate: Evaluation determines if the test is fit for its intended use, considering factors such as the target population, clinical setting, and existing diagnostic options.
Cost-Effective: While not directly addressed in pre-clinical evaluation, thorough assessment helps avoid the promotion and use of tests that may offer limited clinical benefit or are too expensive for widespread adoption.
Describe the importance of pre-clinical evaluation in the development of a new diagnostic test.
Pre-clinical evaluation is crucial because it allows researchers to thoroughly assess the performance and safety of a new diagnostic test before it is used on human subjects. This stage helps to identify any potential issues or limitations with the test, ensuring that it is both safe and effective for its intended use.
Explain the difference between repeatability and reproducibility in the context of diagnostic testing.
Repeatability refers to the ability of a test to produce consistent results when performed multiple times under the same conditions, such as in the same laboratory by the same operator using the same equipment.
Reproducibility, on the other hand, refers to the ability of a test to produce consistent results when performed under different conditions, such as in different laboratories, by different operators, or using different equipment.
What are the main components of “Analytical Performance Characteristics” that are evaluated during pre-clinical analysis? Briefly describe each component.
Analytical Sensitivity: The lowest amount of the target analyte that the test can reliably detect (Limit of Detection or LOD).
Analytical Specificity: The ability of the test to accurately measure only the target analyte and avoid cross-reactivity with other substances in the sample, minimizing false positives. It also includes assessing for interferences that might cause false-negative results.
Linearity: The ability of the test to provide results that are proportional to the concentration of the analyte across the entire measuring range of the test. This means that the test should be accurate at both low and high concentrations of the analyte.
Spike and Recovery: This assesses if the test is affected by the composition of the sample (matrix effects). It involves adding a known amount of analyte to a sample and measuring how much is recovered, ensuring the accuracy of the test in different sample types.
List and explain three tools that can be used to assure the quality of diagnostic testing.
Quality Assurance (QA): A comprehensive set of procedures and practices designed to monitor and evaluate the entire testing process. This includes things like staff training, equipment calibration, regular assessment of testing procedures, and implementation of corrective actions to ensure accurate, reliable, and timely patient results.
Internal Quality Control (IQC): The routine use of control samples with known values to monitor the performance of a test within a laboratory. This helps to detect any variations in the test’s performance over time and ensure that results are consistent and accurate. IQC involves specific procedures, materials, testing frequency, and acceptable limits for the results obtained with control samples.
External Quality Assessment (EQA): Participation in programs where a laboratory’s performance is compared to other labs using samples with unknown values. This is an objective way to assess the accuracy and reliability of a lab’s testing and identify any systematic biases or errors. EQA programs are often run by independent organizations and provide valuable feedback to laboratories on their testing performance.
Why is it essential to have clear and comprehensive labeling requirements for diagnostic tests?
Safety: Clear instructions and warnings help to minimize the risk of errors during testing and ensure the safety of both users and patients.
Effective Use: Detailed information on the test’s intended use, sample collection, test procedure, and interpretation of results is crucial for healthcare professionals to perform the test correctly and obtain accurate results.
Consistency: Standardized labeling ensures that all tests within a product line are used in a consistent manner, reducing variability and improving the reliability of results.
Traceability: Information such as the manufacturer’s name and contact details, lot number, and expiration date allows for tracking of the test in case of any quality issues or recalls.
Informed Decisions: Providing information on the test’s limitations, expected values, and performance characteristics enables healthcare professionals to make informed decisions about using the test and interpreting its results.
Explain the purpose and importance of “Labelling Requirements” for diagnostic tests.
identification: Clear labeling with the test’s name, intended use, and manufacturer information.
Instructions: Detailed steps for sample collection, preparation, test procedures, and result interpretation.
Reagents and Materials: Information on the components of the test kit, including storage and handling requirement
Performance Characteristics: Data on the test’s analytical and clinical performance, such as sensitivity, specificity, accuracy, and precision.
Limitations: Clear statements outlining the test’s limitations, potential interferences, and any factors that may affect results.
Safety Precautions: Warnings and safety information to protect users from potential hazards associated with the test.
Comprehensive labeling is crucial for:
Ensuring Proper Use: Clear instructions and information help users perform the test correctly and minimize the risk of errors.
Interpreting Results: Information on performance characteristics and limitations allows healthcare professionals to accurately interpret test results and make informed decisions.
Enhancing Safety: Safety precautions and warnings help protect users and patients from potential hazards.
Traceability and Accountability: Labeling with lot numbers, expiration dates, and manufacturer details enables tracking in case of quality issues or recalls.
