![]() ![]() inferior level of evidence compared with prospective studies.may be used as the initial study generating hypotheses to be studied further by larger, more expensive prospective studies.can address rare diseases and identify potential risk factors (e.g.quicker, cheaper and easier than prospective cohort studies.Used if sample size is low and other options failed.More than one confounder is controlled simultaneously, if a larger number of confounders needs to be adjusted for computer software and statistical advice is necessary. ![]() Used if only a few confounders exist and if the size of one of the comparison groups is much larger than the other.Find pairs of patients that have specific characteristics in common, but received different treatments compares outcome only in these pairs.Used if only one key confounding variable exists.Divide all patients into subgroups according to a risk factor, then perform comparison within these subgroups.Used if treatment and control group are selected by a chance mechanism.Compare outcomes between treatment and control group.Unadjusted, univariate, ‘simple’ or ‘raw’ analysis.STATISTICAL ANALYSIS USED IN RETROSPECTIVE STUDIES retrospective cohort studies (current or historical cohorts).Types of retrospective studies include:.Retrospective studies may be based on chart reviews (data collection from the medical records of patients).Retrospective studies are designed to analyse pre-existing data, and are subject to numerous biases as a result. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |