11. Experimental studies

  1. A. Gouveia Oliveira

Published Online: 12 JUL 2013

DOI: 10.1002/9781118670767.ch11

Biostatistics Decoded

Biostatistics Decoded

How to Cite

Oliveira, A. G. (ed) (2013) Experimental studies, in Biostatistics Decoded, John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/9781118670767.ch11

Editor Information

  1. Department of Pharmacy, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil

Publication History

  1. Published Online: 12 JUL 2013
  2. Published Print: 3 SEP 2013

ISBN Information

Print ISBN: 9781119953371

Online ISBN: 9781118670767



  • adaptive clinical trials;
  • alpha spending function;
  • blinding;
  • clinical trials;
  • data record;
  • experimental research;
  • group sequential plans;
  • non-comparative clinical trials;
  • non-inferiority clinical trials;
  • randomization


The main feature of experimental studies, which distinguishes them from observational studies, is that an intervention is applied to the subjects, observing later in time whether a response is seen. The ultimate goal of experimental research is the demonstration of a causal relationship between an intervention and a response, although not all experimental studies have the ability to show causality. This chapter focuses on the methodology of clinical trials, the most common experimental studies in clinical research. It discusses the efficacy criteria, non-comparative clinical trials, controlled clinical trials, classical designs, the control group, blinding, and randomization. The chapter also talks about the size of a clinical trial, non-inferiority clinical trials, adaptive clinical trials, group sequential plans, the alpha spending function, the clinical trial protocol and the data record.