From a brewer to the faraday of statistics: William Sealy Gosset

William Sealy Gosset (1876-1937) was an immensely talented statistician to be remembered for his contributions to the development of modern statistics. Better known to the statistical world by his pseudonym, "Student," Gosset′s name is associated with the discovery of the t-distribution and its use. He was a brewer of Guinness′ Brewery in Dublin, Leinster, Ireland and the pioneer in the analysis of small samples. The most famous work, "The Probable Error of a Mean," published in "Biometrika" made a clear distinction between population parameters and sample estimates of them. He will be remembered as a practical scientist for his discoveries of the frequency distribution of the variance of normal samples and of the ratio of the mean to the standard deviation to the theory of statistics. His life was one full of fruitful scientific ideas that the Student′s test of significance finds a unique place in the history of scientific method

Factors influencing the perceived orthodontic treatment need and its relationship with awareness of malocclusion among college adolescents

Introduction: The orthodontic need assessment is of interest for dental public health programs. The major factors determining a patient′s perceived need for orthodontic treatment may be aesthetic, functional, financial, or social. Adolescents seeking orthodontic treatment have been found to have poorer aesthetics than their peers, but whether poor aesthetics alone generates greater treatment demand has not been determined in the Indian context. Objective: The aim was to study the factors determining perceived orthodontic treatment need among college adolescents. Materials and Methods: A total of 448 adolescents between 17 and 19 years of age were selected randomly from the colleges. Data were collected on pretested and standardized questionnaire. Perceived need for orthodontic treatment was assessed by asking question to the participants. Dental Esthetic Index (DAI) was used to assess the severity of malocclusion. Results: The prevalence of malocclusion was 21.6% as per DAI. The perceived need for orthodontic treatment was 11.2%, though the level of dissatisfaction with dental appearance was 19.2%. No agreement was seen between the treatment need assessed objectively by DAI and that perceived by the patient. The determinants for perceived and normative orthodontic treatment need were socioeconomic status (SES), awareness of malocclusion, dissatisfaction with dental appearance and avoided smile due to dental appearance. The positive correlation between perceived and normative need was statistically significant. Conclusion: The uptake of orthodontic care may be influenced by SES, awareness of malocclusion; dissatisfaction with dental appearance, perceived need and DAI score