Which sampling method is more complex and usually more time consuming to perform?

Random sampling is indeed regarded as a more complex and time-consuming sampling method compared to the other techniques listed. This is primarily because random sampling requires each member of the population to have an equal chance of being selected, which necessitates a well-defined population and potentially complex randomization processes.

To effectively implement random sampling, auditors often need to utilize random number generators or similar tools to ensure that the selection process is indeed random. This adds an extra layer of complexity and may require additional time to plan and perform.

In contrast, interval sampling involves selecting items at regular intervals, which is systematic and relatively straightforward. Systematic sampling also follows a structured approach, but draws samples based on predetermined intervals, making it less complex than random sampling. Judgment sampling relies on the auditor's discretion to choose the sample based on what they deem appropriate, which is typically faster but less rigorously random.

Overall, the intricacies involved in ensuring true randomness and the necessary tools and methods needed to achieve that contribute to the complexity and time consumption associated with random sampling.