Question

+ Name Measures Measures Key differentiating of of Limitations Timing characteristics frequency association Description study Design Ecologic Cross-sectional Case-control Retrospective Cohort Prospective Cohort Experimental
epidemiology class

Answer 1

Ecologic:

• Description: A study of risk modifying factors on health or outcomes based on populations, geographically.
• Disease rates and exposure are measured in each of a series of populations and their relations is examined.

Timings:

• many diseases show remarkable fluctuations in incidence over time.
• Rates of acute infections can vary appreciably over few days, but epedimics of chronic disorders evolve over decades.

Differentiating charcharacteristic

• Identify factors related to the occurrence of disease.
• Its causative agent and risk factors.
• Development of rational basis for prevention.

Measures of frequency

• Number of times plant species occurs in a given number of quadrant measures the frequency.
• The probability of finding a species in a series of quadrants examined in an area of interest.

measures association

• 20 Measures are examined according to the six criteria proposed for ecological coexistence.
• 4 of them satisfy all six criteria.
• 3 of them , suggested by ochiai, dice and jaccard are recommended.

strengths:

• 3 spatial ecosystem service tools : ARIES, INVEST, AND LUCI.
• Ecosystem service support tools range in complexity and sophistication.
• Models run for water supply, carbon storage and nutrient research services.

Limitations:

• Growth explicitly posed in terms of food resources, physical capacity of ecosystem and the territoriality of populations within ecosystems.