Interventional (Experimental) Studies in Veterinary Research & Practice

Interventional studies, especially in laboratory experimental researches, constitute a significant portion of the theses conducted in veterinary faculties across the country. The importance of these study designs in applied research and development underscores the necessity for students and researchers to be familiar with this design. This article begins with a brief history of this type of study. It then proceeds to introduce various types (laboratory, clinical trials, field trials, social trials, quasi-experimental studies), the different phases of this design (pharmacological and toxicity testing, initial testing for potential therapeutic and safety effects, clinical evaluation stage, post-marketing evaluation), and its various methods (parallel design, crossover design, sequential design, factorial design). This article also discusses the required sample size for conducting a study, criteria for entry and exit of study participants or animals, blinding and medical ethics. Given the importance of clinical trials, especially in terms of ethical considerations in research, the registration of this type of study after proposal development is also mentioned. This article refers to some examples of interventional studies published in Iran and worldwide so that students and researchers can use these designs as models. It is expected that the reader could critically read this type of articles and reports, published in scientific texts and play an effective role in conducting an experimental (interventional) study.