the relationship between initial population density of rice white tip nematode (aphelenchoides besseyi) and yield was examined on oryzae sativa cv. alikazemi. experiments were conducted in greenhouse, micro-plot and field conditions. seinhorst’s model was used to describe the relationship between nematode population density and crop yield. the parameters of the model, minimum yield (m), constan...

In a number of important clinical issues such as evaluation of the efficacy or effectiveness of therapeutic or preventive interventions as well as for comparing the harms of interventions, randomized controlled trials (RCTs) provide the highest levels of evidence, either directly or indirectly. It is obvious that critical appraisal of these studies to assess their validity and precision is of p...

there has been too much of a one-way flow drift down a river of evidence. researchers from rich countries have produced the primary evidence which they proceed to summarise within reviews. these summaries have directed care worldwide. however, things are changing and the river of evidence can flow in the other direction. the care of women with eclampsia has been changed or refined throughout th...

participation in clinical trials can be useful for the health of a person, in who it is conducted, but it does not have to be - it can even be harmful. therefore, primary motive to accept such risk is humanity and human wish to contribute to the progress of medicine; this is expressed by personal consent. the consent, however, can be an expression of personal humanity, and for this, it is not l...

conclusions there is not enough evidence to support or refute the routine use of fish oil supplements during pregnancy for the prevention or treatment of diabetes. it is suggested that further randomized controlled trials be conducted to evaluate the role of fish oil supplementation in pregnancy. context one of the most common complications of pregnancy is gestational diabetes mellitus (gdm), w...

stroke is an important cause of death in the world and disability world‑wide especially in developed countries. following acute phase of stroke, some procedures and medical treatment such as thrombolytic agents has been recommended; nevertheless many patients have enduring deficits. thus, there is a realistic need to develop treatment strategies for reducing neurological deficits. however, the ...

Evidence based medicine is very important for success of modern medicine. It is the ongoing process of using the most reliable evidence from clinical studies, scientific understanding and medical practice to make the best possible medical choice for patients. Evidence based medicine is how medicine advances and how we get improvements in life expectancy and quality of life. It not only identifi...

evidence based medicine is very important for success of modern medicine. it is the ongoing process of using the most reliable evidence from clinical studies, scientific understanding and medical practice to make the best possible medical choice for patients. evidence based medicine is how medicine advances and how we get improvements in life expectancy and quality of life. it not only identifi...

In combination with randomization, blinding or masking is an important factor in randomized controlled trials (RCTs), particularly in trials that assess therapeutic effects. Here an attempt is made to explain blindness and why it is important. In clinical trials, blinding is defined as the condition imposed on a study in which study participants, health care providers and assessors collecting o...

introduction: most physicians consider abstracts to give a general idea about the full text of an article. abstracts, as summative and informative parts, contain main information of papers. they also point out the content of papers to readers. the importance of abstracts leads journals to be stricter about their structure and content. this study aimed to assess the abstracts of randomized contr...