 Hello everyone, welcome back to a new session on dentistry and more. So today we have a new topic, survey procedures, survey we have seen survey and we have heard lot about surveys, the survey which is coming just before the election that is political surveys, pre-political surveys, pre-election surveys and survey on various things. So survey is nothing but a part of epitomology or the descriptive part of epitomology. So epitomology we have two major varieties that is descriptive and experimental or you can say observational and experimental. Observational study means the investigator has no special role, nothing but an observer he just collects data and interprets the data. So survey is nothing but an observational epitomology. So let's see the definition of survey. It is an investigation in which information is systematically collected but the experimental method is not used. So like I said there is no experimental method is involved in survey. So survey is like a common man's term, epitomology is more of a kind of scientific term. So the types of survey we have seen this I told you there is no experimental method. So it is nothing but an observational part that is descriptive and analytical. So in descriptive we are just seeing cross-sectional longitudinal and even analytical we have cross-sectional longitudinal. So descriptive study and analytical study, descriptive as a name suggests is just describe a situation like distribution of a disease. We know it is mentioned under time, place and distribution, time, place and person distribution. So analytical means it tries to explain a situation by determinative power like why does the disease occur. This is like where is this occurring, how it is occurring, how fast it is occurring and what are the age groups which is affected. So here it is saying why does the disease occur. So here we formulate the hypothesis in analytical we test the hypothesis and if it is based on the time period we have basically two types that is longitudinal and cross-sectional. So longitudinal is nothing but a follow-up study cross-sectional is only one point of time we will be checking the data of a population. Now let's move on to the oral health service that is basic oral health service. These are particularly on the oral health matters that is defined as a survey to collect the basic information about oral disease status and treatment needs that is needed for planning or monitoring oral health care programs. There is nothing but we do a survey to plan a program or monitor oral health care programs. So these are the basic oral health service that has basically few objectives that is to provide a full picture of the oral health status and needs of a population and to monitor changes in the disease levels or patterns. So these are the objectives of oral health service. So pathfinder service are the common question that has been asked. So pathfinder service is nothing but how the oral health service conducted. So it is like for the past 25 years the practical economical survey sampling methodology by considering special factors associated with oral disease which is known as pathfinder. So the striking feature of pathfinder service is it uses a stratified cluster sampling technique. We have seen sampling designs in detail. So previous videos I mentioned about the sampling techniques, probability and non-probability sampling. So this stratified cluster sampling technique are particularly used in pathfinder method. So while we are using stratified cluster sampling it aims to include the most important population subgroups which are having various disease levels and particular age groups also included. So by this way we can get a very reliable and clinically relevant information for planning a oral health program. So never forget this particular sampling design stratified cluster sampling which is particularly for the pathfinder survey and pathfinder survey is for oral health service. So we have two types of pathfinder survey that is pilot and national pathfinder. So pilot survey is like any research we do pilot study before doing the actual study just to know the feasibility or reliability of the examiners. So pilot survey is just like a pilot seeing from very top of the area. So he can have a very large view but he may need to do it at a proper level so that he will understand what are the limitations or roadblocks he might face in the actual study. So pilot study we do on a pathfinder survey by keeping one or two index ages so index ages we will see in the next slide. So it is like we don't take all the age groups just one or two index age groups and mostly the 12 years will be one among that and we do the pilot survey it will be a very small study. Why we are doing pilot study means it provides minimum amount of data needed to commence planning additional data has to be collected in order to provide a baseline for the implementation and monitoring services. So just to start a plan or before planning we need to do a pilot survey by keeping one or two age groups and the age 12 should be one among that because it is a global monitoring age of dental care is and we can start the program but we need to get more data by conducting national pathfinder survey it is a very big type of service it has to include at least three age groups and most importantly other most importantly it has to include all important subgroups here you can use only most important subgroups so you need to collect people from most of the cities or most of the populations or most of the group where you get the stratified sampling and clusters wherever you get you need to include a national pathfinder survey the aim is to represent a very larger picture not like a pilot survey which gives a very minute or very fraction of the data so national pathfinder survey a minimum three age groups should be there here only one or two age groups okay so let's see what are the age groups index age groups I was talking about these are also known as World Health Organization index age groups or age groups or WHO age groups so it is important that when we are doing a study on oral health these age groups should be included because it has relevance in our oral health age groups are five in number that is first one was five that is for primary dentition then 12 15 35 to 44 I'm 65 to 74 for permanent dentition so why fifth year is important because the level of caries and primary dentition which may exhibit our short time frame so at the age of five we have our perm deciduous molas erupted maybe for two to three years so can have a better look on the dental caries pattern and 12 year is also known as global monitoring age for caries so because it is a age when children leave primary school so therefore it is the last age at which reliable sample may be obtained through the school system because once they are out of the school it is very difficult to collect data so 12 year is very important that is why in pilot study we were including one or two index age group and one among it should be 12 so teeth have erupted except because by 12 years most of the teeth must have erupted except the molas and this is known as global monitoring age for caries for international comparison and monitoring of disease strengths so 15th year by this age permanent teeth have exposed to oral environment for three to nine years so caries experience can be assessed 35 to 44 years like it is a standard monitoring group of health condition adults so the full effect of caries period on the disease are into action so we can easily make out our current do comparison of the caries and period on the status between the people and 65 to 74 this is necessary for planning appropriate care for elderly and the overall effect of oral health care also can be assessed at this age group so the index age group or WHO age groups are 5 12 15 35 to 44 and 65 to 74 in pilot study out of this five two should be included and one should be 12 for national pathfinders away three should be included that is total five are there so out of five there are three should be there for a national pathfinder survey okay so how we conduct a survey it is very similar to our descriptive study because we need to do the objectives establishing the objective then we need to design the investigation sample selection conducting the examination analyzing the data drawing conclusion and publishing the result so objectives means the hypothesis we discussed hypothesis null hypothesis alternate hypothesis everything we are covered in detail so we need to establish a hypothesis then we need to design how we are going to conduct a study based on the objective that is descriptive or analytical so it can be a prevalent study or it can be an incident study it depends upon the nature of disease if it is already occur we can do a prevalent study if it is yet to occur we can do an incident study so incident study are like which is happening in the future so it might take longer duration and it might cost a lot of money and administratively complicated and sometimes we need to keep control so all these are the patterns which we seen in descriptive study and analytical study so we know how to conduct a case control and cohort study we have seen in detail so I am not going very detail about it so you can always go back and check the video where I mentioned in detail about case control cohort study in the epidemiological section and then we need to do the sample selection so selection of sample also we have covered in detail that is probability sample or non probability sample so it depends upon always probability is good because it has equal chance for all participants like simple random stratified systematic and cluster so in pathfinder survey this is a combined stratified and cluster was used stratified cluster sampling so non probability convenience judgmental quarter snowball so I am not going in detail because the same topic we have covered so that was sampling probability and non probability after that we need to do the examination so conducting examination by approving proper role from authorities budgeting we need to schedule it and cases refill validity and reliability of data so instruments examination area all these we need to plan and then we do examination on patients so we have four types of examination this is also very important for the exam types of examination so type one two three and four type one is a complete examination and type four is just using a tongue depressant so always keep in mind type one is the best and type four is the worst okay so keep in mind in that way so type one means we have all the arrangements all the investigations all the equipments to understand a patient's oral health we have mouth mirror explorer illumination radiographs diagnostic methods such as for testing transillumination and lab investigation we have everything to understand a patient's oral health status but the type two is mouth mirror explorer and illumination with radiographs okay so type two is a little bit compromised and type one type three is only mouth mirror explorer and illumination okay so type four is just a screening procedure we use only tongue depressor okay so type two is commonly we use in clinical trials when we do study clinical trials we can use this type two with mouth mirror explorer illumination and radiographs type three in epidemiological service when we go to a field we are doing study on a very large group of people so in epidemiological service we can use mouth mirror explorer and a torchlight for illumination type four is just for inspection of school children in that case we can do so type four is screening type three is a epidemiological survey and type two is clinical trials and type one will be a most accurate and most complete examination so this is the types of examination type one two three and four type one is a complete one and type four is the minimalistic one okay so after that we need to analyze the data how we analyze the data it is based on the risk estimation we know how to conduct a risk estimation relative risk odds ratio so those parameters we have seen and finally we need to reject or accept a hypothesis based and we need to put the conclusion and we can publish our reports okay so that's all about survey method survey method is nothing but epidemiology in the descriptive part we are giving in a more general way epidemiology is very much scientific way so we are expressing the same epidemiology descriptive part or observational study in a more common way that is survey so survey the important things are the types of examination and the sampling and this one the age groups okay pathfinder surveys are common husions and this index age groups a pathfinder survey index age groups sampling and types of examination and survey is a very common essay being asked every every say two years once in two years or every year it's been asked so survey methodology and other short notes are important in this chapter so I'll come up with a new session and understand what I think