By Dr Hidayathulla Shaikh

Objectives At the end of the lecture student should be able to –  Explain types of examination  Discuss different types of pathfinder survey  Explain all ages groups selected in pathfinder surveys.  Discuss the procedure of selection of subjects

Types of Examination Type 1  Complete examination using mouth mirror, explorer, adequate illumination with radiographs.  When indicated percussion, vitality tests, study models, lab test are also done. Type 2  Limited examination, using mouth mirror, explorer, adequate illumination, and posterior bitewing radiographs.

Type 3  Inspection using mouth mirror, explorer and adequate illumination.  This is the most used method in public health surveying. Type 4  Screening using tongue depressor and available illumination.  Many a times this method is unreliable for public health surveying.

5) Analyzing the data  Once the examination procedures of a survey is over, the work of assembling the material and interpreting it begins  Analysis of findings has two components, data processing (statistical analysis) and interpretation of results. 6) & 7) Drawing conclusions & Publishing the report  The conclusions are specifically related to the investigation that has been carried out.  Final step in the survey should be the construction of report

Oral Health Surveys (Pathfinder Survey)  Basic oral health surveys are used to collect information about oral health status and treatment needs.  And subsequently monitor changes in levels and patterns of disease.  Thus it is possible to assess appropriateness and effectiveness of the services being provided.  And plan or modify oral health services as needed.

 The pathfinder method is a “stratified cluster sampling technique”.  It aims to include the most important population subgroups likely to have differing disease levels.  It also proposes appropriate number of subjects in specific index age groups in any one location.  In this way reliable and clinically relevant information for planning is obtained at minimum expense.

Classification  Pathfinder surveys can be classified based on number and type of sampling sites (places or areas) and age groups included, they can be a) Pilot Survey b) National Pathfinder Survey.

A) Pilot Survey  Is one that includes only the most important subgroup in the population.  That is only one or two index ages, usually 12 years and one other age group.  Such a survey provides minimum amount of data needed to start planning.  Additional data should then be collected to provide reliable baseline for implementation of services.

B) National Pathfinder Survey  It includes sufficient examination sites to cover all important subgroups of the population.  Who may have differing disease levels or treatment needs, and at least three of the age groups or index ages are chosen.  This type of survey design is suitable for planning and monitoring of services in all country

 In a large country large number of sampling sites are needed.  Sampling sites are usually chosen, which can provide information on population groups likely to have different levels of oral disease.  Ex - cities, small towns or ethnic groups etc once it is decided random sampling of subject is done to get samples.  The recommended index ages and age groups are 5, 12, 15, and years.

A) 5 years  In this age group children should be examined between their 5 th and 6 th birthdays.  The age is of interest because levels of caries in the primary dentition may show changes over shorter time period.  In some countries 5 years is also the age at which children begin primary school.

B) 12 years  This age is especially important as it is generally the age at which the children leave primary school.  Also, it is at this age that all permanent teeth except 3 rd molars will have erupted.  For these reasons 12 years is chosen as the global monitoring age for caries for international comparisons and monitoring of disease trends.

C) 15 years  At this age the permanent teeth have been exposed to the oral environment for 3 to 9 years.  The assessment of caries prevalence is often more meaningful than at 12 years of age.  This age is also important for the assessment of periodontal disease in adolescents.

D) years (mean 40 years)  This age group is the standard monitoring group for health conditions in adults.  The full effect of dental caries, the level of severe periodontal involvement and general effects of oral care provided can be monitored using data from this group.

E) years (mean 70 years)  This age group has become more important with the changes in age distribution and increase in life span that are now occurring.  Data for this group are needed for planning appropriate care and monitoring over all effects of oral care for elderly people.

How Number of Subjects are selected  The number of subjects In each index age group to be examined ranges from 25 – 50 for each cluster or sampling site.  And depending upon the expected prevalence and severity of oral disease.  If level of oral disease in population is unknown, then level of disease is estimated before starting a survey.  Ex – examining 2 or 3 classes of 12 year old children in 2 or 3 schools.

Ex - Sample Design for a National Pathfinder Survey (usually sampling sites are selected and index age group ranges from 25 – 50 for each cluster or site.  If this cluster distribution is applied to 4 index age groups in population, the total sample will be 4 x 300 =  A 25 subjects per site is selected when caries and periodontal diseases are estimated to be low and very low in population.  In populations where these disease levels are moderate to high the standard size of each sample should be 40 – 50 subjects. Urban4 sites (places) in city4 x 25 = sites in 2 towns2 x 2 x 25 = 100 Rural1 site in each of 4 villages in different regions 1 x 4 x 25 = 100 Total12 sites x 25 subjects300