DEFINITIONS OF BLINDING IN RANDOMISED CONTROLLED TRIALS OF INTERVENTIONS PUBLISHED IN HIGH- IMPACT ANESTHESIOLOGY JOURNALS : A METHODOLOGICAL STUDY

Abstract

Cilj istraživanja: Cilj ovog istraživanja bio je analizirati potpunost izvještavanja o zasljepljivanju u randomiziranim kontroliranim pokusima (engl. randomized controlled trial, RCT) na području anesteziologije, utvrditi status zasljepljivanja sudionika pokusa i iznijeti različite interpretacije zasljepljivanja kojima su se autori koristili u RCT-ovima. Metode: Provedeno je metodološko istraživanje RCT-ova o intervencijama koji su objavljeni od početka 2014. do kraja 2017. u sedam najcitiranijih anestezioloških časopisa. Primarni ishod bio je broj RCT-a koji su jasno opisali tko je bio zaslijepljen tijekom ispitivanja, a sekundarni ishodi bili su definicije pojma zasljepljivanja i terminologije vezane za zasljepljivanje. Rezultati: Glavni rezultati istraživanja pokazuju da čak 38% analiziranih kliničkih pokusa nije eksplicitno opisano kao otvoreno ili zaslijepljeno ispitivanje, a u 10% ispitivanja nisu iznesene nikakve informacije o zasljepljivanju ili izostanku zasljepljivanja. Najčešći izraz o zasljepljivanju u naslovu i cjelovitom radu je da je studija opisana kao dvostruko zaslijepljena. U pogledu potpunosti izvještavanja pronađen je samo jedan rad s potpunim izvještavanjem, 27% radova s djelomičnim izvještavanjem, 51,7% radova s minimalnim izvještavanjem i 21,1% radova bez izvještavanja. Zaključak: Izvještavanje o statusu zasljepljivanja ključnih pojedinaca u RCT-ovima iz područja anesteziologije nije dostatno. U ispitivanjima na području anesteziologije rijetko se navodi tko je bio zaslijepljen, čitatelju se ne pružaju dostatne informacije o zaslijepljenim pojedincima i najčešće se za opisivanje pokusa koristi nejasan izraz dvostruko-zaslijepljeni pokus, koji je podložan različitim interpretacijama.Objectives: The aim of this study was to analyze completeness of reporting of blinding in randomized controlled trials (RCTs) of interventions in the field of anesthesiology, the actual blinding status of various persons associated with an RCT and trial authors’ interpretation of blinding terminology related to RCTs. Methods: This was a methodological study of published RCTs of interventions published from the beginning of 2014 to the end of 2017 in seven highly cited anesthesiology journals. The following data were analyzed:number of RCTs that clearly described who was blinded in a trial, definitions of blinding terminology in the trials and trial authors’ interpretation of blinding terminology. We grouped reporting of blinding in four categories. Results: The main results of our study indicate that as many as 38% of analyzed trials were not explicitly described as either open-label or blinded studies, and 10% did not report any information about blinding or lack of blinding. Most common description related to blinding, both in the title and in the manuscript, was that study was double-blind. With regard to full reporting, we found one manuscript with "full reporting", 27% of the manuscript with "partial reporting", 51.7% of the manuscript with „minimal reporting“ and 21.1% of the manuscript with "no reporting". Conclusion: Explicit and complete reporting of the blinding status of key individuals involved in RCTs is inadequate. Anesthesiology trials rarely report who was blinded, and mostly use ambiguous term double-blind which if not sufficiently informative for readers