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 these type of articles and reports , published in scientific texts and play an effective role in conducting an experimental ( interventional ) study .