Useful links to study and learn.
Data management and planning
Study designs and data collection
Experiment
Survey
Observational study
Meta-analysis
Power and sample size calculations
Exploring data
Variables
Dealing with missing data
Hypothesis testing / how to choose and perform a statistical test
Tests to compare means
Parametric tests: t-test
Anova
Non-parametric tests
Survival times
Logrank test (and kaplan-meier plot)
Evaluating dependencies
Chi-square test of independence
Correlation
Decision curve analysis
Bias
Lists of various statistical techniques
Statistical softwares
Glossaries