Quality and retrieval of obstetrical anaesthesia randomized controlled trials.
OBJECTIVE
Randomized controlled trials (RCTs) are suitable for meta-analysis and systematic reviews provided they are of high quality and are easy to retrieve. We determined these attributes of RCTs in obstetrical anaesthesia in a sample of available journals that are indexed in MEDLINE.


METHODS
Randomized controlled trials published between January 1985 and December 1994 in seven anaesthetic and three obstetric journals were identified by a MEDLINE search, and by handsearch of the same journals. Each RCT was assigned a quality score by a blinded rater using a reliable and validated scaled. The quality of each RCT was described and compared over time and by journal. The comparative yield of MEDLINE and hand-search was evaluated.


RESULTS
Three hundred and forty RCTs were retrieved by MEDLINE and handsearch. Two hundred and twenty seven (65%) were identified by the MEDLINE search and 333 by the handsearch (98%). The median quality score was 3/5. There was no difference in score over time. Anesthesiology had the highest median score, Anaesthesia had the lowest (P < 0.05).


CONCLUSIONS
Care must be taken when reviewing obstetrical anaesthesia research. Strategies in addition to a MEDLINE search must be used to identify RCTs since more than one third were missed using MEDLINE alone. Poor quality RCTs are more likely to be biased in favour of a new treatment. Therefore, to increase the validity of reviews sensitivity analyses based on quality should be done.
Bender
J S
JS
Department of Anaesthesia, Women's College Hospital, Toronto, Ontario, Canada.
Halpern
S H
SH
Thangaroopan
M
M
Jadad
A R
AR
Ohlsson
A
A
D000773:Anesthesia, Obstetrical; D000776:Anesthesiology; D015982:Bias; D005260:Female; D006801:Humans; D016247:Information Storage and Retrieval; D016239:MEDLINE; D010506:Periodicals as Topic; D011247:Pregnancy; D016032:Randomized Controlled Trials as Topic / Q000592:standards*; D015203:Reproducibility of Results; D012107:Research Design; D012680:Sensitivity and Specificity; D016037:Single-Blind Method