- The scientific method. Methodology of investigation.
The Ten Commandments.
- Frequency measures. Ratio. Porportion. Rate.
About chalk and cheese.
From the triangle to the pie.
- Incidence rate. Incidence rate ratio.
Some new come and some others go.
- Association measures. Risk. Relative risk (RR). Risk ratio. Relative risk reduction (RRR). Absolute risk reduction (ARR). Number needed to treat (NNT).
Do they not trick you with cheese.
- NNT’s confidence interval.
The tribulations of an interval.
- NNT’s calculation in meta-analysis.
- Other impact numbres. Impact number in exposed. Impact number in cases. Impact number in exposed cases.
Simplifying the impact.
- Association measures. Odds. Odds ratio.
The one with the foreign name.
- Berkson’s falacy.
Generalizations are hazardous.
- Choosing between risk ratio and odds ratio.
The ratio’s trap.
- Hazard ratio. Cox regression.
The hare and the tortoise.
- Confounding (I). Confounding variable. Confounding factor.
- Confounding (II). Pairing. Cohort studies. Adjusting in case-control studies.
Birds of a feather flock together.
- Confounding (III). Pairing. Matching. Case-control studies.
A matter of pairs.
- Effect modifiers. Interaction. Standardized risk ratio.
Ménage à trois.
- Sampling techniques. Simple random sampling. Stratified random sampling. Non-randomized sampling techniques. Finite sample correction.
An important decision.
- Classification of epidemiological studies.
Which family you belong?
- Cross-sectional studies. Association cross-sectional studies.
That’s not what it seems to be.
- Ecologic studies. Ecological fallacy. Association.
- Cohort studies. Impact measures. Incidence’s difference. Exposed attributable fraction. Population attributable fraction. Impact numbers.
One about Romans.
- Case-control studies. Odds ratio. Selection bias.
From the hen to the chicken.
- Case-crossover studies.
You make your bed, you lie in it.
- Hybrid designs. Cohort nested case control study. Case cohort study.
Togeteher but not in each other’s pockets.
- Randomized clinical trial. Intervention group. Control group. Placebo. Randomization. Follow-up. Per protocolo analysis. Intention to treat analysis. Parallel clinical trial. Equipoise..
King of Kings.
- Types of clinical trials. Cross-over clinical trial. Factorial clinical trial. Sequential clinical trial. Cluster allocation trial. Community trial.
The other sides of the King.
- Crossover clinical trials analysis.
Don’t get your wires crossed.
- Equivalence and non-inferiority trials. Equivalency limits. Clinical relevance. Statistical significance.
The consolation of not being worst.
- Cluster clinical trial.
The gregarious one.
- Factorial clinical trial.
More than one rooster per pen.
- Crossover clinical trial.
- Adaptive clinical trials.
- Pilot studies.
- Run-in phase. Washout period. Clinical trials.
- Intention to treat analysis.
Intention is what matters.
- Contingency tables. Cross-sectional studies. Cohort studies. Case-control studies. Cumulative incidence. Incidence density.
- Masking. Single-blinded. Double-blinded. Triple-blinded.
To see well you must be blind.
- Randomization. Simple randomization. Block randomization. Stratified randomization.
The necessity of chance.
- Composite outcome variables.
Strength through unity.
- Random error. Systematic error.
The fairground shotgun.
- Errors. Random error. Sistematic error. Selection bias. Information bias.
To err is human.
- Preventive trial biases. Participation bias. Lead time bias. Length time bias.
The sun is not hurried by early risers.
- Diagnostic tests (I). Sensitivity. Specificity. Positive predictive value. Negative predictive value. Likelihood ratio. Pre-test probability. Post-test probability. Probabilities ratio.
All that glitters is not gold.
- Diagnostic tests (II). Sensitivity. Specificity. False positive. False negative. ROC. Cutoff.
The guard’s dilemma.
- Diagnostic tests (III). Screening. Early diagnostic. Primary prevention.
Prevention not always is better.
- Diagnostic tests (IV). Sensitivity. Specificity. Positive predictive value. Negative predictive value. Screening. Prevalence calculation.
The imperfect screening.
- Diagnostic tests (V). Diagnostic threshold. Treatment threshold.
Crossing the threshold.
- Diagnostic tests (VI). Accuracy index. Youden’s index. Number needed to diagnose. Number needed to misdiagnose one.
The turn of the screw.
- Diagnostic tests (VII). Diagnostic odds ratio.
A never-ending story.