TABLE 1

Critical appraisal of randomised controlled trials using National Institute for Health and Care Excellence standards#

First author, year [ref.]RandomisationAllocation concealmentBlindingFollow-upSelective reportingStatistical analysis plan
Tashkin, 2007 [12]YesUnclearYesNoNoUnclear
Tashkin, 2016 [13]YesUnclearYesNoNoYes
Sircar, 2017 [14]YesUnclearNoUnclearNoUnclear
Pérez Campos, 2012 [15]YesYesYesNoNoUnclear
Seibold, 2010 [16]UnclearUnclearYesNoNoUnclear

#: a further study was underpowered and therefore not rated at the same evidence level [11]; : please note that since the date of the literature search, this reference (abstract) has been published in full.