1. By Dr Hidayathulla Shaikh

2. Objectives  At the end of the lecture student should be able to –  Define survey  Mention uses of survey  Discuss types and evaluation of questionnaire  Explain steps in surveying

3. Introduction  Survey is defined as “a non experimental type of research that attempts to gather information about the present condition of the large number of people without directly analyzing their causes”.  In other terms it is a non experimental investigation in which information is systematically collected, but with no active intervention by the investigators.  The purpose of most survey is to collect information that will provide a basis for action, whether immediately or in long term.

4. Types of Surveys 1) Descriptive or Analytical 2) Cross sectional or Longitudinal Uses of Surveys 1) Monitoring trends in oral health and disease 2) Policy development 3) Program evaluation 4) Assessment of dental needs 5) Providing visibility for dental issues.

5. Methods of Data Collection – 1) Health Interview Survey (face to face survey)  It is an important method of measuring subjective phenomena such as disability, belief, attitude and behavior characteristics.  However data may not be fully reliable because of some interview limitations.

6. 2) Health Examination Survey  It is carried out by a team of doctors and assistants and is more reliable than health interview survey.  Its disadvantage is it is expensive and can not be carried out on the large group.

7. 3) Health Record Survey  It involves collection of data from health service records.  The disadvantage is that the data obtained is not population based. 4) Questionnaire Survey  The use of questionnaire and interview is a standard method of data collection in clinical, psychological and epidemiological research.  Taking medical history is also a form of questionnaire interview.

8. Types of Questionnaire Survey A) Mailed – here questionnaire requires a literate respondent, and despite of low cost it results in high rate of non response. B) Telephone - interviews are easy to conduct who have phone, but miss those who do not have phone or who are at work. C) Face to Face – interviews are commonest type used in community surveys and clinical research.  However the best is face to face survey because it allows clarification of questions, answers can be probed and hence response rate is high.

9. Questions used in Questionnaire Surveys 1) Open ended questions (Free response)  The subject answers his own words, but sometimes may be difficult to interpret the response.  Its is better to keep them few because respondent can talk freely at any length of time. Ex - how many cigarettes you smoke per day?

10. 2) Closed ended question (Fixed alternative)  They are answered by choosing from a number of fixed alternative responses.  They make for greater uniformity and simplify the analysis and are there fore preferred for most purposes.  For ex – how many cigarettes you smoke per day a) upto 5 b) 6-10 c) 11-15 d) more than 15

11. Scales used to Measure and Analyze questions Likert scale  Commonly used to measure attitudes and behavior, respondents are asked to select response that best represents their answer.  Ex – the respondent may be asked to indicate whether he Strongly agrees, agrees, cant say, disagree or strongly disagree for any statement.

12. Guttman scale  These contain series of statements that express increasing intensity of characteristics.  The respondent is asked to agree or disagree with each statement, and final score is the total number of items with which he agrees or disagrees.

13. Steps in Surveying 1) Establishing the objectives 2) Designing the investigation 3) Selecting the sample 4) Conducting the examination 5) Analyzing the data 6) Drawing the conclusions 7) Publishing the results. 1) Establishing the objectives  The investigator must be absolutely clear about the objective of the investigation before the start of the survey.

14. 2) Designing the investigation  Important to prepare survey protocol which contains objectives, information to be collected, sampling method, finance, timetable and responsible staff.  Approval should be obtained from proper authority, and should be ready to handle emergency care.

15. 3) Selecting the sample  Usually it impossible to examine every individual in the population so representative sample is selected.  Errors like observer error, instrumental error and sampling error should be minimized.

16. 4) Conducting the examination A) Scheduling  An orderly schedule should be prepared for data collection, to prevent the waste of time.  Basic oral health examination of a child takes approximately 5-10 mins and for an adult 15-20 mins.  It is not advisable to schedule more than 15 children to examine in one hour.

17. B) Instruments and supplies  Plane mouth mirrors and periodontal probes 30 per examiner should be provided.  Along with several pair of tweezers, concentrated sterilizing solution, cloth or paper hand towels and gauze.

18. C) Infection control  Current recommendations should be followed for both infection control and waste disposal.  The use of disposable masks, gloves and the wearing of protective glasses are recommended.

19. D) Examination area  The basic requirements for an oral examination are chairs, tables, source of light, & adequate supply of assessment forms.  Also advisable to have organizing clerk to maintain constant flow of subjects to examiners and to enter information in assessment forms.

20. E) Training and Calibrating Examiners  When an epidemiological survey is undertaken by a team, it is essential that all examiners be trained to make consistent results.  It will ensure uniform interpretations of codes and criteria of various diseases and conditions to be observed.