Sommario
Come si legge il rischio relativo?
Il rischio relativo o risk ratio (RR) è il rapporto tra i due rischi assoluti: RR= 0.14/0.18=0.78.
Come si calcola l incidenza cumulativa?
Il calcolo dell’incidenza cumulativa è semplice e si effettua come segue: (nuovi casi) / (popolazione a rischio all’inizio dell’osservazione). Con i dati della Tabella, il calcolo è il seguente: 8/20 = 0.4, ossia 40% in 5 giorni.
What is an odds ratio?
An odds ratio is the odds of the event in one group, for example, those exposed to a drug, divided by the odds in another group not exposed. Odds ratios always exaggerate the true relative risk to some degree. When the probability of the disease is low (for example, less than 10%), the odds ratio approximates the true relative risk.
How do you calculate odds ratio in case control studies?
It quantifies the relationship between an exposure (such as eating a food or attending an event) and a disease in a case-control study. The odds ratio is calculated using the number of case -patients who did or did not have exposure to a factor (such as a particular food) and the number of controls who did or did no t have the exposure.
What is the percent difference between marginal and conditional odds ratios?
Marginal odds ratio ignoring age=1.93 Conditional odds ratios 1.48 and 1.54 Conditional odds ratios are similar but not equal, different from marginal odds ratio Percent differences of conditional odds ratios (1.93-1.54)/1.93=0.2, (1.93-1.48)/1.93=0.23 When the percent differences between marginal and conditional odds ratios are more than 10%,
How do you calculate the odds ratio of exposure?
The odds ratio is calculated using the number of case -patients who did or did not have exposure to a factor (such as a particular food) and the number of controls who did or did no t have the exposure. The odds ratio tells us how much higher the odds of exposure are among case-patients than among controls.