between samples may be present. For example, multiple independent samples may each be collected as part of a different independent studies that were conducted at different historical times using different sampling mechanisms, experimental procedures, and psychometric instruments. Thus what constitutes a “separate” sample ultimately resides on a continuum and some common research designs within clinical psychology that are typically not considered pooled data analysis (e.g., multi-site trials) may also benefit from consideration of the issues raised in the IDA framework.
