Parotid swelling DDx
Parotid swelling or enlargement can be unilateral or bilateral, suggesting different underlying causes.
Month January 2019
Mirizzi syndrome
Mirizzi syndrome or extrinsic biliary compression syndrome, is a rare complication of cholelithiasis. Mirizzi syndrome is characterised by obstruction of the common bile duct (CBD), secondary to mechanical compression caused by the impaction of one or multiple gallstones in the neck of the gallbladder or cystic duct
Best Case/Worst Case – a communication tool
“Best Case/Worst Case” is a communication tool to help doctors explain to patients and their families what different treatment options really mean.
Confounding and Confounders
Confounding involves error in the interpretation of what may be an accurate measurement by attributing it to the wrong cause. A confounder is a factor that is prognostically linked to the outcome of interest and is unevenly distributed between the study groups
Bias in Research
Bias is the systematic distortion of the estimated intervention effect away from the "truth", caused by inadequacies in the design, conduct, or analysis of a trial
Incidence and prevalence
Incidence = number of individuals who develop a disease in a given period of time. Prevalence = the current number of cases in a given population
Linear regression and Correlation
Linear regression and correlation used to compare the relationship between two variables where the relationship appears to be continuous (e.g. tachycardia and blood loss)
Levels and Grades of Evidence
Different systems of categorising the quality of evidence, and individual studies, have been developed; primarily used in evidence-based clinical guidelines
Measures of Central Tendency
Measures of Central Tendency; these indices allow a sample or population to be summarised using a single value.
Odds ratio
An odds ratio (OR) is a measure of association between an exposure and an outcome. The OR represents the odds that an outcome will occur given a particular exposure, compared to the odds of the outcome occurring in the absence of that exposure.
Power and Sample Size
It is unethical and a waste of time and resources to embark on a study when there is a high chance of a false negative result (Type II error). The commonest cause of this is having a sample size that is too small
Qualitative Data Types and Tests
Qualitative data consists of categorical measurements determined by description rather than a numerical measurement