A comparison of two forms of teaching instruction: video vs. live lecture for education in clinical periodontology.

INTRODUCTION: This crossover controlled study aimed to compare the knowledge and skill attained by third-year dental students in three clinical exercises in the discipline of periodontology through video and live lecture instruction. METHODS: Students (n = 35) segregated into two group either viewed a video or attended a live lecture repeated over three clinical teaching sessions. Pre-test and post-test written assessments were completed and comparisons between video and live lecture done (analysis of variance, P < 0.05). Students were assessed on clinic by a simple checklist. A questionnaire was administered after all three sessions to determine preferences and opinions on video and live lecture. RESULTS: For the combined three sessions, both video (n = 48) and live lecture (n = 47) groups attained similar mean pre-test scores. The mean post-test score was statistically significantly greater (P = 0.049) for the live lecture (74.9%, SD 14.9) compared to the video group (68.6%, SD 16.3). All students attained clinical proficiency via the simple checklist. In adding to their clinical skill, more students favoured video (97%) vs. live lecture (78.8%). Most students (97%) favoured a future combination of video and lecture. DISCUSSION: While students were deemed clinically competent via a simple checklist, the live lecture group performed better than the video group via the in-depth post-test assessment. Students had a preference for video and would like it integrated in the lecture rather than act as a substitute for the lecture. CONCLUSION: The use of video alone in clinical periodontology training may have limitations unless supplemented by appropriate learning activities.

SU-E-T-189: Arc Splitting for VMAT Patient QA.

PURPOSE: To determine the need for arc splitting for VMAT prostate patient quality assurance. METHODS: Prior to Eclipse version 10.0, a verification plan for VMAT treatment could only be created which mirrored the clinical plan; if the plan called for a full arc, then the verification plan also contained a full arc. In this case, for a center that uses the Sun Nuclear MapCheck device with its Isocentric Mounting Fixture, the full fluence of an arc is delivered en face to the device. The question arose as to whether partial arcs, if they could be created, would fail a center's criteria, while the full arc passed them, in effect, whether there are cancellations occurring and not being observed. With Eclipse version 10.0, it is now possible to split a clinical arc into many subdivisions for verification, the software recommends no more than 40 partial arcs, for computing speed limitations. Twelve VMAT plans for prostate patients were investigated, in order to search for the aforementioned cancellations. Two full arcs were used clinically in all cases. Verification plans were created consisting of (1) the two full arcs; (2) 8 partial arcs of 90 degrees each; and (3) 16 partial arcs of 45 degrees each. These were all analyzed against our criteria of 3%/3mm with a threshold of 10%, and 95% of points passing. RESULTS: Of 288 partial arcs and 49,670 points analyzed, there were a total of 100 points (0.2%) that failed the 3%/3mm criteria. No arcs, however, failed the 95% passing criteria. Moreover, there was no evidence of cancellation; if a point failed low, there was no corresponding high failure in another partial arc. CONCLUSIONS: In this study, splitting a full arc into partial arcs revealed no unseen failures.

An urban outbreak of visceral leishmaniasis in Natal, Brazil.

The epidemiological pattern of visceral leishmaniasis in north-eastern Brazil is changing. The disease was typically seen in rural, endemic areas, but is now occurring as an epidemic in the city of Natal where 316 cases have been reported since 1989; 49% were in children less than 5 years of age. The principle clinical and laboratory findings were weight loss, fever, hepato-splenomegaly, anaemia, leucopenia and hypergammaglobulinaemia. Elevated transaminases and hyperbilirubinaemia were also observed. The diagnosis was confirmed in 87% of cases by identifying amastigotes in aspirates from bone marrow or spleen. Five isolates were identified as Leishmania (L.) chagasi by isoenzyme analysis. The mortality rate was 9%; all deaths occurred during the first week in hospital. One person had concurrent human immunodeficiency virus infection. Among 210 household contacts and neighbours of patients from the endemic area examined for evidence of L. (L.) chagasi infection, 6 additional cases of visceral leishmaniasis were diagnosed. Thirty-eight percent of house-mates and neighbours gave a positive Montenegro skin test reaction, indicating prior subclinical infection.

Differentials in the rate of fertility decline: 1960-1970.

The continuous decline in fertility in the United States since 1957, while affecting all elements of the population, has been most pronounced and most rapid among those groups which previously had the highest fertility - blacks, American Indians and Mexican Americans-all of whom experienced fertility declines more rapid than those experienced by urban whites between 1957-1960 and 1967-1970. Among urban whites, fertility decline has been heavily concentrated among those of low income. The decline was especiallyrapid for third and higher order births, suggesting a heavy concentration of completed fertility at two-child families. The rapid decline, and the narrowing of the traditionalfertility differentials among various subgroups have important implications in the areasof poverty, education, the role of women in society and the dynamics of local area growth.

PIP: The fertility decline between 1957 and 1973 for various ethnic, economic, and social subgroups within the U.S. population is detailed by comparing the fertility change of currently married women between the periods 1957-1960 and 1967-1970. In order to analyze differential rates of fertility decline for population groups of greatest interest it was necessary to use an indirect method. Data in this article are taken from the 1960 and 1970 Census of Population which includes the household composition along with age of each member. Measure of fertility was the average number of children under age 3 living in the same household with their own mother, married and under age 40. This approximates the number of births a woman has had in the past 3 years by looking at the number of children under age of 3 living with her in the household, and, in the same way, can identify the number of births each woman had in a previous year from number of children under age of 1 living with her. Shortcomings to this method are listed. Fertility declines have been more rapid during 1957-1960 and 1967-1970 among blacks, American Indians and Mexican Americans -- groups which previously had the highest fertility -- than among urban whites. Among urban whites, fertility decline has been heavily concentrated among those of low income. The decline was particularly rapid for 3rd and higher order births, indicating a possible concentration of completed fertility at 2-child families. The rapid decline and the narrowing of traditional fertility differentials among various subgroups have important implications in the areas of poverty, education, the role of women in society, and the dynamics of local area growth.