Murray W. Enkin

Do practice guidelines guide practice? The effect of a consensus statement on the practice of physicians.

Guidelines for medical practice can contribute to improved care only if they succeed in moving actual practice closer to the behaviors the guidelines recommend. To assess the effect of such guidelines, we surveyed hospitals and obstetricians in Ontario before and after the release of a widely distributed and nationally endorsed consensus statement recommending decreases in the use of cesarean sections. These surveys, along with discharge data from hospitals reflecting actual practice, revealed that most obstetricians (87 to 94 percent) were aware of the guidelines and that most (82.5 to 85 percent) agreed with them. Attitudes toward the use of cesarean section were congruent with the recommendations even before their release. One third of the hospitals and obstetricians reported changing their practice as a consequence of the guidelines, and obstetricians reported rates of cesarean section in women with a previous cesarean section that were significantly reduced, in keeping with the recommendations (from 72.2 percent to 61.1 percent; P less than 0.01). The surveys also showed, however, that knowledge of the content of the recommendations was poor (67 percent correct responses). Furthermore, data on actual practice after the publication of the guidelines showed that the rates of cesarean section were 15 to 49 percent higher than the rates reported by obstetricians, and they showed only a slight change from the previous upward trend. We conclude that guidelines for practice may predispose physicians to consider changing their behavior, but that unless there are other incentives or the removal of disincentives, guidelines may be unlikely to effect rapid change in actual practice. We believe that incentives should operate at the local level, although they may include system-wide economic changes.

A randomized clinical trial of the Leboyer approach to childbirth.

To examine the effects of the Leboyer method of delivery, we randomly assigned 56 women to either a Leboyer or a conventional delivery and used a variety of clinical and behavioral measures to assess the outcome in mother and child. No differences were noted in maternal or newborn morbidity, in infant behavior in the first hour of life, at 24 or 72 hours post partum, or at eight months of age; or in maternal perceptions of her infant and the experience of giving birth, except that eight months after delivery, mothers who had used the Leboyer method were more likely to say that the event had influenced their childs behavior (P = 0.05). Women who expected a Leboyer delivery had shorter active labors (P = 0.03), suggesting that psychologic factors (expectations) influence physical outcomes in perinatal medicine. Our results suggest that the Leboyer procedure has no advantage over a gentle, conventional delivery in influencing infant and maternal outcomes.

Obstetrical attitudes and practices before and after the Canadian consensus conference statement on cesarean birth

This paper describes one aspect of a research program aimed at reducing the incidence of cesarean section in Ontario for women with a previous cesarean section or a breech presentation. Using data from multiple sources--surveys of obstetricians, and hospital administrators, and hospital record statistics, the authors attempt to assess the response of obstetricians to pressure to change their practice. This pressure comes principally from the Canadian Consensus Conference Statement on Cesarean Birth, released in June 1986 and subsequently endorsed by a number of professional organizations. The Statement provides clear guidelines for the management of labour in women with previous cesarean section or a breech presentation. The findings present a number of interpretive challenges. Based on their response to hypothetical cases obstetricians are favourably disposed to considering a trial of labour for women with previous cesarean section and breech presentation. However, both their reported practices, as well as hospital statistics indicate the continued high prevalence of cesarean section, though there is a small decline in cesareans for previous cesarean section. There was no evidence that hospitals lacked appropriate facilities for a trial of labour or had unduly restricted formal policies. Furthermore, although awareness of and agreement with the Consensus Statement recommendations was high, when questioned on the actual details of the recommendations, obstetricians recall was surprisingly low. Respondents tended to err in the direction of choosing more conservative measures than those recommended by the Statement.(ABSTRACT TRUNCATED AT 250 WORDS)

Six myths about controlled trials in perinatal medicine

Despite a historical commitment to evaluation of the results of practice, obstetrics has missed many opportunities to assess new therapies adequately prior to their widespread use. Although randomized controlled trials are generally recognized as the best method of evaluating therapy, a number of myths about these trials have impeded both their performance and the implementation of their results. The unscientific nature of these myths is discussed, and examples from the perinatal literature are presented.

Systematic summaries and dissemination of evidence: The cochrane pregnancy and childbirth database

It is surely a great criticism of our profession that we have not organised a critical summary, by specialty or subspecialty, adapted periodically, of all relevant randomised controlled trials . . . . The profession has a primary duty to its patients to help discover the most effective therapies . . . . It is therefore not unreasonable to judge our profession and its specialties by the use they have made of the randomized controlled trial t e c h n i q u e . . . . Of all medical specialities it is in obstetrics and gynaecology in which clinical practice is least likely to be supported by scientific evidence. 9 . . After due thought and meditation, but without prayer, I awarded them the wooden spoon.

The outcome of prolonged labor as defined by partography and the use of oxytocin: A descriptive study

A descriptive study of 300 consecutive spontaneous labors in primigravid patients whose pregnancies were of 37 or more weeks gestation with a singleton fetus in the vertex presentation, showed a cesarean section rate of 13%, a forceps delivery rate of 49%, and a spontaneous delivery rate of 38%. Oxytocin was used in 17% and epidural analgesia was used in 75% of the patients. The median rate for cervical dilatation for those women with spontaneous deliveries was 2 cm/hr (interquartile range = 1.5 to 3.3 cm/hr) and for those delivered with forceps, 1.2 cm/hr (interquartile range = 0.9 to 1.8 cm/hr). When labor was prolonged by 4 hours or more, the cesarean section rate rose to 34%. Oxytocin was used in only 41% of these patients. Of 23 women delivered by cesarean section for dystocia/disproportion, only nine received oxytocin. From the low incidence of low Apgar scores in all labor groups from this series, there would not appear to be a fetal advantage to earlier intervention. Although the suggestion from this study is that oxytocin administration when labor is prolonged by 4 hours will reduce the need for cesarean section, the true value of such an intervention can be tested only by a randomized controlled trial.

Observations on the behavioral state of newborn infants during the first hour of life A comparison of infants delivered by the Leboyer and conventional methods

Minute-by-minute observations are reported on the behavioral state during the first hour of life of 18 term infants delivered by the Leboyer (L) method and 18 by the conventional (C) method. The mothers were unmedicated and only two women in each group received epidural anesthetics. All deliveries were spontaneous and the infants were healthy. The behavioural states of both groups of infants were very similar, with the infants spending approximately 60% of the first hour in the quiet-alert state (median time: L = 41.5 C = 35.0 minutes) and only 10% of the time in the irritable-crying state. ALthough there were some individual differences, both groups of infants spent the second 30 minutes of the first hour predominantly in the quiet-alert state. The clinical relevance of these observations is that the first hour of life can be used to advantage in promoting parent-infant interaction.

Collecting the Evidence Systematically: Ensuring That It Is Complete and Up-to-Date

A complete and comprehensive search of the relevant evidence is an essential step in the preparation of a scientific systematic review. The Cochrane Pregnancy and Childbirth Database consists of some 600 systematic reviews, based on almost 6,000 randomized or quasi-randomized trials of care during pregnancy and childbirth. As ascertainment from electronic search of the National Library of Medicine MEDLINE database was not complete, the mainstay of our search strategy was a systematic hand search of some 60 journals, beginning with volumes published in 1950. Additional references were obtained from the list of references in primary research reports and conference reports. A major effort was made to identify unpublished trials and to obtain unpublished data from published trials.

Randomized Controlled Trials in the Evaluation of Antenatal Care

Many of the practices carried out during antenatal care improve the well-being of mother or baby and reduce the burden of adverse perinatal outcome. Other practices have either not been evaluated or have been shown to be ineffective. Evidence from randomized clinical trials provides the best evidence about the effectiveness of these practices.

Questioning the methodological superiority of 'placebo' over 'active' controlled trials.

Pity the poor placebo. The term placebo (from the Latin to please) was used in the 13th century to name the Roman Catholic Vespers of the Office of the Dead. It acquired its pejorative sense when the Vespers came to be sung by hired mourners, who sold their services as professional grievers. These ‘placebos’ of their day nevertheless provided a valuable service for those who could not (or would not) grieve properly on their own. Medicine began to adopt the term in 1785 as “a medicine given more to please than to benefit the patient” (Online Etymology Dictionary 2001). Despite their derogatory definition, these medical placebos also served a useful function, and acquired a new respectability. Sometimes, apparently working through the power of suggestion, they were the only thing that would help a patient. Why should a doctor withhold any comfort that was hers to offer? (Harrington 2006) Alternative forms of health care thrived during the 19th and early 20th century. Despite the many testimonials to their success, non-orthodox treatments were challenged by the mainstream to ‘prove’ the efficacy of their treatments, by subjecting patients to placebo or fake versions of the treatment to see whether they respond just as well as to the ‘real’ thing. Conventional medical practitioners did not feel they had to subject orthodox medicine to similar tests until much later. By the last quarter of the 20th century, however, responsible clinicians began to recognize that clinical impression and expert opinion might not be enough, even for themselves. The new paradigm of evidence-based medicine revived and re-honored the much maligned placebo, this time not to praise it as a source of consolation in the clinic, but to condemn it as a source of bias to be controlled for in the testing situation, a bias that could affect physician and patient alike (Harrington 2006). A personal note: I have often used placebos throughout my (perhaps overly) long career, but I never felt comfortable with them, either as treatment or as control. I wanted to use the best treatment for my patients, even though I did not know what the best treatment was. I needed guidance, and appealed to the experts. As a student I looked to my teachers, as a general practitioner I looked to the specialist to provide the answers. When I became a specialist I looked to the academics, even became one, but my ignorance persisted and grew (Enkin 2008). As a researcher I bowed to the