in 17 hospitals, 13123 new births were born during 1989 in tehran. some well-trained personnel observed the events, filling the required questionnaires, interviewing, and collecting necessary information. among them 730 newborns was low birth weight (less than 2500 grams) which was considered as cases. immediately after each case was born, two normal newborn were randomly selected as controls. ...

background: thyroid cancer is the most common endocrine malignancy. several risk factors were found to play a role in thyroid cancer. the purpose of the study was to determine the risk factors for thyroid cancer, in babol, north of iran. method: 80 patients with thyroid cancer were selected as case group and 160 people living in the neighborhood of the patients as control group. risk factors in...

normal 0 false false false en-us x-none ar-sa microsoftinternetexplorer4 background : according to beck theory, dysfunctional attitude has a central role in emergence of depression. the aim of this study was to determine contributions of dysfunctional attitude and general health index to depression. methods : in this case-control study, two groups of subjects participated. the first group consi...

Odds ratio (OR) is a statistic commonly encountered in professional or scientific medical literature. Most readers perceive it as relative risk (RR), although most of them do not know why that would be true. But since such perception is mostly correct, there is nothing (or almost nothing) wrong with that. It is nevertheless useful to be reminded now and then what is the relation between the rel...