Jankovic Slobodan M, Masic Izet
Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia.
Academy of Medical Sciences of Bosnia and Herzegovina, Sarajevo, Bosnia and Herzegovina.
Acta Inform Med. 2020 Mar;28(1):4-11. doi: 10.5455/aim.2020.28.4-11.
Results of preclinical and clinical studies in medicine could be trusted only if their design and statistical analysis were appropriate.
The aim of our study was to investigate whether preclinical and clinical studies published in medical journals of Bosnia and Herzegovina satisfy basic requirements for appropriate design and statistical interpretation of data.
Preclinical and clinical studies published in medical journals of Bosnia and Herzegovina were retrieved from the PubMed database, and the sample for analysis was randomly chosen from the retrieved publications. Implementation rate of basic principles of experimental design (local control, randomization and replication) and rate of the most common errors in design of clinical/observational studies was established by careful reading of the sampled publications and their checking against predefined criteria.
Our study showed that only a minority of experimental preclinical studies had basic principles of design completely implemented (7%), while implementation rate of single aspects of appropriate experimental design varied from as low as 12% to as high as 77%. Only one of the clinical/observational studies had none of the errors searched for (2%), and specific errors rates varied from 10% to 89%. Average impact factor of the surveyed studies was around one, and average publication date recent, less than 5 years ago.
Prevalence of preclinical studies that did not follow completely basic principles of research design, and that of clinical/observational studies with errors are high, raising suspicion to validity of their results. If incorrect and not protected against bias, results of published studies may adversely influence future research.
只有医学临床前研究和临床研究的设计与统计分析恰当，其结果才可信。
我们研究的目的是调查在波斯尼亚和黑塞哥维那医学期刊上发表的临床前研究和临床研究是否满足数据恰当设计和统计解释的基本要求。
从PubMed数据库检索在波斯尼亚和黑塞哥维那医学期刊上发表的临床前研究和临床研究，并从检索到的出版物中随机选取分析样本。通过仔细阅读抽样出版物并对照预定义标准进行核对，确定实验设计基本原则（局部控制、随机化和重复）的实施率以及临床/观察性研究设计中最常见错误的发生率。
我们的研究表明，只有少数实验性临床前研究完全实施了设计基本原则（7%），而适当实验设计单个方面的实施率从低至12%到高达77%不等。临床/观察性研究中只有一项没有所查找的错误（2%），具体错误发生率从10%到89%不等。所调查研究的平均影响因子约为1，平均发表日期较近，不到5年前。
未完全遵循研究设计基本原则的临床前研究以及存在错误的临床/观察性研究的比例很高，这引发了对其结果有效性的怀疑。如果已发表研究的结果不正确且未防止偏差，可能会对未来研究产生不利影响。
