EVALUATION OF RESEARCH STUDIES

Clinical practice is often based on the results of research. Critical evaluation of research studies is important if appropriate conclusions are to be drawn. In this series of columns, we review principles of research methodology and statistical analysis. Our intent is to assist certified nurse-midwives in understanding the relative merits of the research they read and use. This article, the first of the series, will review issues pertinent to randomized clinical trials.     

EVALUATION OF RESEARCH STUDIES

Reading and interpreting research studies is an important and necessary activity of clinical practitioners. Correct evaluation of research findings requires appreciation of certain fundamentals of research methodology and statistics. This article, the third of the series, will review issues pertinent to statistical significance testing.     

EVALUATION OF RESEARCH STUDIES

The concepts of validity and reliability are defined within the context of applied clinical research. Validity concerns what an instrument measures and how well it does so. Reliability concerns the faith that one can have in the data obtained from use of an instrument, that is, the degree to which any measuring tool controls for random error. The researcher selects a measure that demonstrates content, criterion, or construct validity, according to the intended use of the measurement tool. Similarly, the researcher selects a measure that demonstrates a degree of reliability that is needed for its application. It is possible to have reliability without validity, but it is logically impossible to demonstrate that an unreliable test is valid.     

EVALUATION OF RESEARCH STUDIES

Clinical practice is often based on the results of research. Critical evaluation of research studies is important if appropriate conclusions are to be drawn. In this series of columns, we review principles of research methodology and statistical analysis. Our intent is to assist certified nurse-midwives in understanding the relative merits of the research they read and use. This paper, the second of the series, will review issues pertinent to observational study design.     

NORPLANT皮下埋植避孕剂使用的有效性及其副反应的评价

本研究于1984年10月至1987年9月应用Norplant皮下埋植剂1470人(其中Nor-Plant-Ⅰ1169人,Norplant-Ⅱ301人)控制生育。12个月和24个月的避孕效果:累积的妊娠率分别为0.2%和0.3%,持续使用率分别为96.5%和86.2%。主要副反应:月经不规则是终止使用的主要原因;但总失血量不多。Norplant埋植剂使用1年和2年后测定血红蛋白均值略有升高;血压无变化;体重略有增加。埋植剂的放置和取出易于掌握,在1470名使用者中未发生感染或其他并发症,使用安全。由于其妊娠率低和不可能脱落及其高度可逆性,深为受试者所欢迎。     

检测人精子授精能力的综合评分法

对115例精液进行体外授精实验和精液分析。结果说明人精子授精能力在种族上无差异;在受精过程中,精子活动率(M)、精卵亲合率(B)、精子授精率(F)和原核形成率(P)之间均呈正相关,因而提出了一个利用SPA实验原理测定上述四个指标来综合评价精子授精能力的简便易行的新方法,其符合率达94%以上。