Study Design


To provide accessible and accurate guidance in the design of observational studies.

Key Principles

There already exist several guidelines for reporting the findings of observational research, notably the STROBE Statement and various extensions, e.g. when using routinely collected data (RECORD), or when examining genetic associations (STREGA).

TG5 focus is on developing guidance for planning observational studies. Key steps are: 1) define study objectives, 2) select the best design that minimizes threats to validity while acknowledging practical constraints, and 3) outline the main analytical approaches to ensure analyses are in accord with study aims.

Key Messages

  1. Clearly define measurable study research questions.

  2. Know the data and consult content experts as needed to carefully consider practical constraints and limitations of data sources.

  3. Design the study to answer the specific research questions, acknowledging practical limitations that threaten validity.

Topic group 5 is a member of the STRATOS Initiative (STRengthening Analytical Thinking for Observational Studies) which is a large collaboration of experts in many different areas of biostatistical research. Ongoing research, discussions and activities within STRATOS are conducted in nine topic groups and several cross-cutting panels.