GUIDELINE FOR REPORTING NEGATIVE STUDIES IN BIOMEDICAL JOURNALS

As initial opinion/assessment of study is done by reading abstract hence abstract should provide clear and overall information of full text without any selective reporting. It is usually observed that abstracts do not providehence abstract should provide clear and overall information of full text without any selective reporting. It is usually observed that abstracts do not provide sufficient information of the study and more of the emphasis is usually given on the positive findings. Sometime a positive subgroup analysis is given more wattage than negative primary endpoints. [7,8] Abstract should contain sufficient methodological information and the results should be mentioned on the basis of primary and secondary endpoints in sufficient detail without any selective reporting of only positive findings. Study design like superiority, equivalence, non-should contain sufficient methodological information and the results should be mentioned on the basis of primary and secondary endpoints in sufficient detail without any selective reporting of only positive findings. Study design like superiority, equivalence, noninferiority, observational etc. should be mentioned in sufficient detail. Deepak Saxena, et al. Guideline for Reporting Negative Studies in Biomedical Journals National Journal of Physiology, Pharmacy & Pharmacology | 2014 | Vol 4 | Issue 3 | 252 – 254 INTRODUCTION In the introduction aims and objective of the study should be clearly mentioned. It should reflect whether the aim is to show superiority or equivalence? Primary and secondary endpoint should be mentioned and if there is any plan of subgroup analysis then it is also to be mentioned. We have observed that in many published negative studies primary aim was to show superiority but when authors failed to reject null hypothesis then they claim equivalence which is totally inappropriate as equivalence cannot be claimed on the basis of superiority design. [1,2] Hence in the introduction, intention of authors regarding superiority/inferiority should be clearly mentioned. If the study is preliminary or pilot in nature then reason for this should also be mentioned. MATERIALS AND METHODS The design of the study mentioned should be in an accepted terminology. We had observed that many different terminologies were used for study designs in the published negative studies which caused lots of confusion. Design of the study should be mentioned in accepted terminology either as per the journal instructions or laid down by some international agencies like centre for evidence based medicine. [9] In the case of clinical trials superiority/equivalence/non-inferiority should be mentioned. Sample size calculation should be mentioned in detail as per the study designs. [10] All components of sample size calculation should be mentioned with justifications. In case of sample size of non-inferiority or equivalence design appropriate sample size formula based on confidence interval should be used. [11,12] One of the most important reason for getting no significant difference is less power of the study. Hence sample size calculation should be done with adequate power and that should be reported in the published article.