The quality of nifedipine studies used to assess tocolytic efficacy: a systematic review.

Abstract

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.

• Authors: 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, Steering Group of the International Preterm Labour Council
• Journal: Journal of perinatal medicine (J Perinat Med) Vol. 33 Issue 4 Pg. 287-95 ( 2005) ISSN: 0300-5577 [Print] Germany
• PMID: 16207113 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review, Systematic Review)

Chemical References

• Tocolytic Agents
• Nifedipine

Topics

• Female
• Humans
• Nifedipine (therapeutic use)
• Obstetric Labor, Premature (prevention & control)
• Pregnancy
• Publications (standards)
• Randomized Controlled Trials as Topic (standards)
• Tocolytic Agents (therapeutic use)