BMJ's How to Read a Paper Series | |
Systematic Review
A summary of the clinical literature. A systematic review is a critical assessment and evaluation of all research studies that address a particular clinical issue. The systematic review may also include a quantitative pooling of data, called a meta-analysis.
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course
Randomized Controlled Trial
A controlled clinical trial that randomly (by chance) assigns participants to two or more groups. There are various methods to randomize study participants to their groups.
Example:
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course
Cohort Study (Prospective Observational Study)
A clinical research study in which people who presently have a certain condition or receive a particular treatment are followed over time and compared with another group of people who are not affected by the condition.
Example:
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course
Case-control Study
Case-control studies begin with the outcomes and do not follow people over time. Researchers choose people with a particular result (the cases) and interview the groups or check their records to ascertain what different experiences they had. They compare the odds of having an experience with the outcome to the odds of having an experience without the outcome.
Example:
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course
Cross-sectional study
The observation of a defined population at a single point in time or time interval. Exposure and outcome are determined simultaneously.
Example:
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course
Case Reports / Case Studies
A report on a particular patient or program with an outcome of interest. No control group is involved.
Example:
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course
Ideas, Editorials, Opinions
Opinions from experts in the field. Often interesting, but not a peer reviewed item.
Example:
Adapted from Study Designs; in NICHSR Introduction to Health Services Research: a Self-Study Course