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1.
Am J Clin Nutr ; 85(1): 285S-288S, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17209211

RESUMO

A protective effect of folate against the development of neural tube defects (NTDs), specifically, anencephaly and spina bifida, is now well recognized, having been established by a chain of clinical research studies over the past half century. This article summarizes the more important of these studies, which have led to the current situation in which all women capable of becoming pregnant are urged to ingest folic acid regularly. The recommended intakes are 4 mg/d for those at high risk (by virtue of a previous NTD pregnancy outcome) and 0.4 mg/d for all others. However, a reduction in NTD births did not follow promulgation of these recommendations, and so folic acid fortification was mandated in the United States and some other countries. Although some controversy remains about the adequacy of fortification levels, the process was followed by significant improvement in folate indexes and a reduction of 25-30% in NTD frequency (about one-half of the proportion of cases assumed to be responsive to folate). The folate-NTD relation represents the only instance in which a congenital malformation can be prevented simply and consistently. Nevertheless, several research gaps remain: identification of the mechanism by which the defect occurs and how folate ameliorates it; characterization of the relative efficacy of food folate, folic acid added to foods, and folic acid by itself; delineation of the dose-response relations of folate and NTD prevention; and more precise quantification of the dose needed to prevent recurrences.


Assuntos
Ácido Fólico/administração & dosagem , Alimentos Fortificados , Defeitos do Tubo Neural/prevenção & controle , Adulto , Relação Dose-Resposta a Droga , Medicina Baseada em Evidências , Feminino , Ácido Fólico/efeitos adversos , Humanos , Recém-Nascido , Masculino , Defeitos do Tubo Neural/epidemiologia , Gravidez , Resultado do Tratamento , Estados Unidos/epidemiologia
3.
Obstet Gynecol ; 123(2 Pt 1): 353-355, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24402593

RESUMO

Statistical analysis has become integral to the planning, conduct, and reporting of modern medical research. Attention to the statistical aspects of manuscripts submitted to Obstetrics & Gynecology goes back approximately 40 years and the process used in their evaluation has evolved over that time. For the past 20 years, submissions with any type of statistics and being seriously considered for acceptance have routinely been reviewed by a Statistical Editor who judges the work on a number of statistical and design characteristics. Findings of the statistical design review (which has been done by one Statistical Editor over the entire 20-year period) are integrated into the editorial decision about acceptance. The statistical review generally leads to rejection of approximately 16-25% of manuscripts and in a larger proportion, it identifies less serious problems, the correction of which improves the final product.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Políticas Editoriais , Ginecologia , Obstetrícia , Interpretação Estatística de Dados , Estudos de Avaliação como Assunto , Feminino , Humanos , Manuscritos Médicos como Assunto , Editoração
7.
Obstet Gynecol ; 101(5 Pt 1): 846, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12738138
15.
Eur J Obstet Gynecol Reprod Biol ; 108(1): 112-3, 2003 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12694985
17.
Obstet Gynecol ; 119(5): 1048-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22525918
19.
JAMA ; 287(21): 2794-5, 2002 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-12038914

RESUMO

CONTEXT: To compare telephone, fax, and e-mail methods of prodding tardy reviewers. METHODS: Randomized trial conducted January 1998 through June 1999 at the main editorial office of Obstetrics & Gynecology. Reviewers who had failed to file reviews by 28 days after being sent manuscripts (7 days after deadline) were sent identical messages in oral (telephone) or written (fax and e-mail) form inquiring as to the status of review, asking for its completion as soon as possible, and requesting it be sent by fax or e-mail. RESULTS: Of 378 reviewers, proportions returning reviews within 7 days were essentially identical: telephone, 85 (68%) of 125; fax, 86 (67%) of 129; and e-mail, 84 (67%) of 124 (P =.59). In the two thirds who responded, the mean time to return reviews did not differ among the 3 groups. CONCLUSION: Contacting tardy reviewers resulted in a review being received within 7 days in about two thirds of cases, and it made no difference if the contact was made by telephone, fax, or e-mail.


Assuntos
Redes de Comunicação de Computadores , Revisão da Pesquisa por Pares/métodos , Telefac-Símile , Telefone , Manuscritos Médicos como Assunto , Publicações Periódicas como Assunto , Distribuição Aleatória
20.
JAMA ; 287(21): 2795-6, 2002 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-12038915

RESUMO

CONTEXT: Some journals routinely query potential referees before sending manuscripts ("askfirst"), whereas others just send manuscripts and allow referees to opt out ("justsend"). It is not known which protocol results in more completed reviews or shorter review time. METHODS: Trial to assess proportion of referee turndowns and length of review process, conducted at editorial office of Obstetrics & Gynecology and involving 283 consecutive qualifying manuscripts. For each, a referee was randomly assigned to askfirst (manuscript sent only after affirmative response within 3 days) and another to justsend (manuscript sent with request to review; could opt out). RESULTS: Only 64% of askfirst referees assented initially (15% declined [vs 8% for justsend, P =.008] and 21% failed to respond within 3 working days, necessitating a replacement). But once manuscript was mailed, mean time to file a review was significantly shorter for askfirst (21.0 vs 25.0 days, P<.001); thus, overall time to receipt of review did not differ significantly (24.7 vs 25.9 days, P =.19), nor did review quality (P =.39). CONCLUSION: Askfirst led to a higher rate of referee turndown than did justsend, but assenting askfirst referees completed reviews faster. The overall time for the review process did not differ between the 2 protocols.


Assuntos
Revisão da Pesquisa por Pares/métodos , Manuscritos Médicos como Assunto , Publicações Periódicas como Assunto , Distribuição Aleatória
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