van der Wijden C L, Overbeke A J
Nederlands Tijdschrift voor Geneeskunde, Amsterdam.
Ned Tijdschr Geneeskd. 1993 Aug 7;137(32):1607-10.
To collect all randomized clinical trials (RCT) published in the Nederlands Tijdschrift voor Geneeskunde (Ned Tijdschr Geneeskd) in order to present them to the Cochrane Centre, Oxford, United Kingdom, to be included in the international database of RCT's, which will be used to perform meta-analyses.
Retrospective bibliometric study.
Editorial office of Ned Tijdschr Geneeskd.
All original papers (OP), published between the May 1st, 1948 and May 1st, 1993 were studied. Papers were selected that met the criteria for RCT: randomization or the similar assignment of patients to different treatment groups.
Of 6820 OP 259 (3.8%) were selected. In 69 (26.6%) randomization seemed to be performed correctly and in 20 (7.7%) randomization was not correct; in 170 (65.6%) there was no randomization. In the period May 1st, 1948 till May 1st, 1968 24 RCT's were published, in the period May 1st, 1973 till May 1st, 1993 60. Most RCT's (78%) describe the effects of pharmaceutical treatment.
RCT's as such were difficult to recognize in Ned Tijdschr Geneeskd. Over the years there was an increase in the number of published RCT's. The problems we found with the design of RCT's and randomization are still current. An international register of published and/or planned RCT's, as envisaged by the Cochrane Centre, will make it easier to carry out meta-analyses.
收集发表在《荷兰医学杂志》（Ned Tijdschr Geneeskd）上的所有随机临床试验（RCT），以便提交给英国牛津的Cochrane中心，纳入RCT国际数据库，该数据库将用于进行荟萃分析。
回顾性文献计量研究。
《荷兰医学杂志》编辑部。
研究1948年5月1日至1993年5月1日期间发表的所有原创论文（OP）。选择符合RCT标准的论文：将患者随机分配或类似地分配到不同治疗组。
在6820篇原创论文中，259篇（3.8%）被选中。其中69篇（26.6%）随机分配似乎正确，20篇（7.7%）随机分配不正确；170篇（65.6%）未进行随机分配。1948年5月1日至1968年5月1日期间发表了24项RCT，1973年5月1日至1993年5月1日期间发表了60项。大多数RCT（78%）描述了药物治疗的效果。
在《荷兰医学杂志》中，此类RCT很难识别。多年来，发表的RCT数量有所增加。我们在RCT设计和随机分配方面发现的问题仍然存在。正如Cochrane中心所设想的，建立已发表和/或计划中的RCT国际登记册将使荟萃分析更容易进行。
