Epidemiological measures.

These are measures used to determine the prevalence of dental fear in populations. They are valuable for research and manpower and resource planning. Tools that have and can successfully be used for this purpose are the various existing psychometric scales.

Psychometric measures are inexpensive, flexible, easy to administer and often result in continuous score ranges that can easily be compiled and processed statistically. Examples of psychometric measures include the children?s fear survey schedule (CFSS) developed by Scherer and Nakamura². It consists of 80 items on a 5-point Likert-scale. It has been demonstrated to have high reliability and validity for measuring dental fear in children. The cumbersome nature of the questionnaire designed to be filled by the child patient has limited its use despite established validity report².

The Dental Subscale of Children?s Fear Survey Schedule (CFSS-DS) developed by Cuthbert and Melamed³ consists of fifteen items and each item can be given five different scores ranging from "not afraid at all (1)" to "very much afraid (5)". It is a well known instrument for measuring dental anxiety in children. The CFSS-DS has a total score range of 15 to 75 and a score of 38 or more has been associated with clinical dental fear^3-5. It can be used to differentiate patients with high and low dental fears. Its reliability and validity has been aptly demonstrated^6-8. Parents fill the questionnaire for evaluation of dental anxiety levels in the young children because of the child?s inability and probable difficulty to comprehend the content of the questionnaire and the parent?s ability to predict their child?s fear levels with some degree of accuracy^9-11.

Although parents are required to fill the schedule for their children, older children can also fill the questionnaire for self evaluation. The inability of young patients to fill these questionnaires themselves is a limiting factor as the opinion of very young children cannot be obtained directly.

There is also a constructed Short Form of the Dental Subscale of the Children?s Fear Survey Schedule (DFSS-SF) earlier used in the study by Carson and Freeman¹² based on the knowledge from other scales. It is a shorter form of the CFSS-DS consisting of only eight items, with a possible total score ranging from 8 to 40. It measures dental fears in children. The schedule was tested for reliability and validity by Folayan and Otuyemi¹³. It was found to be highly reliable and had moderate significant correlation with the Frankl?s behavioural scale and a dichotomy scale. A cut off point of 19 was established as the measure for clinical dental fear; scores 19 and above indicating dental anxiety¹⁴ while scores above 23 indicating high dental anxiety¹⁵.

A factor analysis of the CFSS-DS by ten Berge et al¹⁶ suggest that this instrument essentially measures a one dimensional concept of dental fear; fear of invasive dental procedures. Also the questionnaire is often filled by the child before treatment. This is contrary to the design as CFSS-DS is supposed to be filled after treatment as it measure trait fear. This measure may give false results as a child may experience anticipatory anxiety prior to treatment that would be expressed in the filled questionnaire as opposed to fear relating to the dental procedure in the here and now¹².

Although psychometric scales have been popularly used over the years to assess dental fear in children, they still present a challenge to researchers. Apart from the issue of restricted age use due to the problem of comprehension of its contents, there are more fundamental issues with the schedules such as the interpretation and meaning a child gives to the various words in the questionnaire at various ages and levels of maturity.