Stratified random sampling is a method of sampling that divides a population into smaller groups that form the basis of test samples.

A simple random sample is a subset of a statistical population where each member of the population is equally likely to be chosen.

For example, if you were carrying out research about the catering facilities in your school, a stratified sample would involve you dividing up the school into different groups.

A swab-sampling method was developed for cleaning validation of a residual active pharmaceutical ingredient in samples collected after cleaning the sampling suite. A summary of the strategies and ...

Random sampling using quadrats Sampling of the area you are studying must be random. It must show no bias – for instance, choosing to sample where there are lots of plants.

Crayfish are widely recognized as an important ecological component of stream systems, but there has been limited work to develop and evaluate the reliability of sampling methods for lotic crayfishes, ...

This study reports a validated rapid, low-volume LC–MS/MS method capable of simultaneously quantifying remifentanil, etomidate, and rocuronium across a wide concentration range.