Ronnie F. Lamont, Khalid S. Khan, Bryan Beattie, Luis Cabero Roura, Gian Carlo Di Renzo, Joachim W. Dudenhausen, Hanns Helmer, Jens Svare, Herman P. van Geijn, Herman P. van Geijn
The quality of nifedipine studies used to assess tocolytic efficacy: a systematic review
Objective: To assess the quality of studies of nifedipine used to treat spontaneous preterm labor.
Design: A systematic review of study quality using a novel validity assessment tool, examining method-specific and topic-specific items in the domains of selection, performance and measurement biases.
Data Sources: Medline (1996–2003), EMBASE (1996–2003), BIOSIS (1993–2003), Current Contents (1995–2003), DERWENT DRUGFILE (1983–2003), Cochrane Database of Systematic Reviews. Bibliographies of existing meta-analyses and systematic reviews of nifedipine as a tocolytic.
Methods of Study Selection: Forty-five studies evaluating the effectiveness of nifedipine were identified.
Data Extraction: Each study was assessed for 40 method-specific and topic-specific items of quality in duplicate using piloted data extraction forms. Disagreements between assessors were settled by consensus/arbitration.
Data Synthesis: Very few of the studies complied with adequacy criteria of quality for either method-specific or topic-specific items. There was no improvement in quality over time. The quality of method-specific items was significantly poorer when compared with topic-specific items of quality overall (P<0.0001) and in the domains of selection bias (P<0.0001) and performance bias (P<0.0001).
Conclusion: Studies of the effectiveness of nifedipine as a tocolytic are of poorer quality with respect to method-specific items than topic-specific items. These deficiencies should be highlighted in meta-analyses or systematic reviews which measure efficacy and should influence the generation of guideline statements or recommendations for the use of nifedipine as a tocolytic. A large randomized trial fulfilling the quality items is necessary to assess the real efficacy of nifedipine in preterm labor.
Journal of Perinatal Medicine, Walter de Gruyter
Print ISSN: 1619-3997
Volume: 33, 07/2005
Pages: 287 - 295
Show full article (external site)
Show all available items of this journal
Search
