### Approach

• Statistical Significance

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## Statistical Significance

Aka: Statistical Significance, Statistically Significant, P-Value, Confidence Interval, Clinical Significance, Clinically Significant
1. Definitions: Statistical Significance
1. Statistical Significance is the probability that study findings are due to chance
1. The risk of rejecting the null hypothesis when it is actually true
2. In planning a study, a level of risk is chosen (e.g. 5% risk or P-Value of 0.05)
2. P-Value is used to denote significance
1. P-Value < 0.05: <5% that findings due to chance
2. Reflects reproducibility of the study findings only
3. Does not predict individual patient's effect
3. Confidence Interval
1. Provides a range of possible outcomes
2. Example: Number Needed to Treat ranges from 20 to 100
3. More clinically relevant
4. Statistical Significance does not mean clinically useful
1. See Clinical Significance below
2. Definitions: Clinical Significance
1. Reflects how much of an effect a patient sees
2. Example:
1. Study shows drug x significantly improves Hair Growth
2. Reality: Even the patient cannot see the difference

### Confidence Intervals (C0009667)

Definition (NCI) A range of values for a parameter that may contain the parameter and the degree of confidence that it is in fact there.
Definition (MSH) A range of values for a variable of interest, e.g., a rate, constructed so that this range has a specified probability of including the true value of the variable.
Concepts Quantitative Concept (T081)
MSH D016001
English Confidence Intervals, Interval, Confidence, Intervals, Confidence, Confidence Interval, confidence interval, confidence intervals
Swedish Konfidensintervall
Czech konfidence - intervaly
Finnish Luottamusvälit
Russian DOVERITEL'NYE INTERVALY, ДОВЕРИТЕЛЬНЫЕ ИНТЕРВАЛЫ
French Intervalles de confiance
Croatian POUZDANOST, INTERVALI
Polish Przedziały ufności
German Konfidenzintervalle
Italian Intervalli di confidenza
Dutch Betrouwbaarheidsinterval, Betrouwbaarheidsintervallen, Interval, betrouwbaarheids-
Portuguese Intervalos de Confiança
Spanish Intervalos de Confianza
Sources
Derived from the NIH UMLS (Unified Medical Language System)