Epidemiology: Benefits and Indexes

Benefits of Epidemiology

• Epidemiology helps in identification of etiological factors
• Epidemiology assists in the planning of oral health services
• It supports curriculum planning
• It aids in estimating manpower
• It assists the evaluation of preventive programs

Index

• An index expresses clinical observations in numeric values

Purpose of Index

• The main purpose of an index in dental epidemiology is to increase understanding of disease processes
• The index helps discover populations at high and low risk
• Indexes can lead to methods of control and prevention

Criteria for Selection of Index

• Indexes have a simple use and calculation
• Indexes permit examination of many people in a short period
• They have criteria which defines its components clearly and readily
• Indexes are free from subjective interpretation
• They define clinical condition objectively
• Indexes are highly reproducible when used by one or more examiners
• They are amenable to statistical analysis
• Indexes strongly relate numerically to clinical stage of specific disease under investigation
• They are equally sensitive throughout the scale
• They do not cause discomfort to the patient

Classification of Indices

• Based on direction, indices can be irreversible or reversible
• Based on the disease, indices can be diseased, symptom, or treatment indexes

Types of Indices

• There are three types of indices
• Reversible indices are for gingivitis
• Irreversible indices are for destructive conditions like periodontitis
• Combined type indices are both reversible and irreversible