What are the Epidemiological Methods Used to Study Sperm Concentration?

Epidemiologists use various methods to study sperm concentration, including:

Cross-sectional studies: These studies assess sperm concentration in a population at a single point in time.
Cohort studies: These follow a group of individuals over time to observe changes in sperm concentration and identify potential risk factors.
Case-control studies: These compare men with low sperm concentration to those with normal levels to identify factors associated with reduced sperm concentration.
Randomized controlled trials: These can test interventions aimed at improving sperm concentration.