Sample dimensioning in epidemiological surveys based on the change of the dental caries prevalence and their implications in the costs

Orientadores: Glaucia Maria Bovi Ambrosano, Antonio Carlos PereiraDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo do presente estudo foi analisar como a prevalência e a distribuição da cárie dentária em escolares influencia no tamanho da amostra necessária em levantamentos epidemiológicos e, conseqüentemente, nos custos para realização dos mesmos pelos serviços públicos. Foram utilizados dados secundários de levantamentos de dois municípios de médio porte do estado de São Paulo, relativos à idade de 12 anos, sendo 1449 escolares de Bauru examinados nos anos de 1976, 1984, 1990, 1994 e 2001 e 1763 examinados em Piracicaba nos anos de 2001 e 2005. As amostras foram dimensionadas levandose em consideração a média e desvio padrão obtidos nos estudos, fixando-se erro amostral (d) em 1, 2, 5 e 10% da média. Após o dimensionamento das amostras, foram estimados os custos para os levantamentos de cárie considerando os preços reais dos materiais e mão-de-obra, incluindo os seguintes itens: material permanente, material de consumo e recursos humanos. Em ambos os municípios, foi constatada a necessidade de aumento no tamanho das amostras em decorrência da diminuição da prevalência da cárie dentária e aumento na variabilidade entre os escolares. Considerando erro amostral de 10%, no município de Bauru, a variação no tamanho da amostra seria de 119 em 1976 para 1118 em 2001. No município de Piracicaba os valores variam de 954 para 1252, em 2001 e 2005, respectivamente. Em relação aos custos para realização dos levantamentos epidemiológicos no município de Bauru foram estimados R$385,00 para o ano de 1976 e R$ 3.617,30 para 2001. No município de Piracicaba, os valores são de R$3.086,70 em 2001 para R$ 4.050,80 em 2005. Os valores mencionados se referem ao custo operacional, pois em ambos os municípios também foi estimado um custo fixo de R$1.190,00 referente ao material permanente. Conclui-se que a diminuição da prevalência da carie dentária determinou a necessidade de um aumento no tamanho das amostras e como conseqüência elevação dos custos e do tempo necessário para realização dos levantamentosAbstract: The objective of the present study was to analyze how the prevalence and the distribution of dental caries in schoolchildren influence the size of the necessary sample in epidemiological surveys and, consequently, in the costs for the completion of similar ones for public services. Secondary data of two medium load municipal districts in São Paulo state were used. 12-year-old age children were examined. 1,449 schoolchildren from Bauru were examined during 1976, 1984, 1990, 1994, and 2001. 1,763 were examined in Piracicaba during 2001 and 2005. The samples were dimensioned according to the average and standard deviation obtained in the studies. The amostral error was set (d) to 1, 2, 5 and 10$ 182,00 in 1976 and US$1.706,00 in 2001. In Piracicaba, the values were US$ 1.456,00 in 2001 and US$1.910,00 in 2005. The stated values refer to the operational cost, because, in both municipal districts, an additional fixed cost of US$ 561,00 regarding the permanent material was estimated. It is ended that the decrease of the prevalence of the dental caries determined the need of an increase in the size of the samples and, as a result, the increase in costs and time for completion of the surveysMestradoSaude ColetivaMestre Profissional em Odontologi

Sample size and costs estimate in epidemiological survey of dental caries

O objetivo do presente estudo foi analisar como a prevalência e a distribuição da cárie dentária influenciam o tamanho da amostra em levantamentos epidemiológicos, e os custos para sua realização. Foram utilizados dados de levantamentos realizados em escolares de 12 anos em Bauru nos anos de 1976, 1984, 1990, 1994 e 2001, e em Piracicaba nos anos de 2001 e 2005. Os tamanhos amostrais foram dimensionados considerando-se a média e o desvio padrão obtidos, fixando-se erro amostral em 1%, 2%, 5% e 10%. Os custos foram estimados considerando material permanente, de consumo e recursos humanos. Verificou-se aumento no tamanho das amostras em ambos os municípios, variando de 119 em 1976 para 1.118 em 2001 em Bauru, e de 954 em 2001 para 1.252 em 2005 em Piracicaba, considerando-se um erro amostral de 10%. Considerando-se diferentes erros amostrais, verificou-se o custo para o levantamento, sendo que o mesmo depende do quanto o pesquisador se permite errar em relação ao verdadeiro valor da média da população. Conclui-se que a diminuição da prevalência da cárie dentária determinou o aumento no tamanho das amostras e a elevação dos custos para realização dos levantamentos

Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study

BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348

[sample Size And Costs Estimate In Epidemiological Survey Of Dental Caries].

This study aimed to analyze how the prevalence and the distribution of dental caries influence the sample size in epidemiological surveys, and how much are the costs. Secondary data of oral health surveys in 12-year-old schoolchildren from Bauru in 1976, 1984, 1990, 1994, and 2001, and from Piracicaba in 2001 and 2005 were studied. Sample sizes were estimated taking into account the mean DMFT and standard deviation of each survey, establishing sampling errors of 1%, 2%, 5%, and 10%. Costs were estimated considering permanent material, consumption material and human resources. The sample size in both towns needed to be increased, ranging from 119 in 1976 to 1,118 in 2001 in Bauru, and from 954 in 2001 to 1,252 in 2005 in Piracicaba, when a sampling error of 10% was considered. The cost of dental caries surveys was verified considering different sampling errors. This cost depends on how acceptable is the margin of difference between the true mean and the one found in the survey. In conclusion, the reduction in the prevalence of dental caries has determined the need for increase in sample size and in costs for conducting the surveys.1596-10

Sample size and costs estimate in epidemiological survey of dental caries

This study aimed to analyze how the prevalence and the distribution of dental caries influence the sample size in epidemiological surveys, and how much are the costs. Secondary data of oral health surveys in 12-year-old schoolchildren from Bauru in 1976, 1984, 1990, 1994, and 2001, and from Piracicaba in 2001 and 2005 were studied. Sample sizes were estimated taking into account the mean DMFT and standard deviation of each survey, establishing sampling errors of 1%, 2%, 5%, and 10%. Costs were estimated considering permanent material, consumption material and human resources. The sample size in both towns needed to be increased, ranging from 119 in 1976 to 1,118 in 2001 in Bauru, and from 954 in 2001 to 1,252 in 2005 in Piracicaba, when a sampling error of 10% was considered. The cost of dental caries surveys was verified considering different sampling errors. This cost depends on how acceptable is the margin of difference between the true mean and the one found in the survey. In conclusion, the reduction in the prevalence of dental caries has determined the need for increase in sample size and in costs for conducting the surveys.O objetivo do presente estudo foi analisar como a prevalência e a distribuição da cárie dentária influenciam o tamanho da amostra em levantamentos epidemiológicos, e os custos para sua realização. Foram utilizados dados de levantamentos realizados em escolares de 12 anos em Bauru nos anos de 1976, 1984, 1990, 1994 e 2001, e em Piracicaba nos anos de 2001 e 2005. Os tamanhos amostrais foram dimensionados considerando-se a média e o desvio padrão obtidos, fixando-se erro amostral em 1%, 2%, 5% e 10%. Os custos foram estimados considerando material permanente, de consumo e recursos humanos. Verificou-se aumento no tamanho das amostras em ambos os municípios, variando de 119 em 1976 para 1.118 em 2001 em Bauru, e de 954 em 2001 para 1.252 em 2005 em Piracicaba, considerando-se um erro amostral de 10%. Considerando-se diferentes erros amostrais, verificou-se o custo para o levantamento, sendo que o mesmo depende do quanto o pesquisador se permite errar em relação ao verdadeiro valor da média da população. Conclui-se que a diminuição da prevalência da cárie dentária determinou o aumento no tamanho das amostras e a elevação dos custos para realização dos levantamentos.9610

Morbidity and mortality after anaesthesia in early life: results of the European prospective multicentre observational study, neonate and children audit of anaesthesia practice in Europe (NECTARINE)

Background: Neonates and infants requiring anaesthesia are at risk of physiological instability and complications, but triggers for peri-anaesthetic interventions and associations with subsequent outcome are unknown. Methods: This prospective, observational study recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. The primary aim was to identify thresholds of pre-determined physiological variables that triggered a medical intervention. The secondary aims were to evaluate morbidities, mortality at 30 and 90 days, or both, and associations with critical events. Results: Infants (n=5609) born at mean (standard deviation [sd]) 36.2 (4.4) weeks postmenstrual age (35.7% preterm) underwent 6542 procedures within 63 (48) days of birth. Critical event(s) requiring intervention occurred in 35.2% of cases, mainly hypotension (>30% decrease in blood pressure) or reduced oxygenation (SpO2 <85%). Postmenstrual age influenced the incidence and thresholds for intervention. Risk of critical events was increased by prior neonatal medical conditions, congenital anomalies, or both (relative risk [RR]=1.16; 95% confidence interval [CI], 1.04-1.28) and in those requiring preoperative intensive support (RR=1.27; 95% CI, 1.15-1.41). Additional complications occurred in 16.3% of patients by 30 days, and overall 90-day mortality was 3.2% (95% CI, 2.7-3.7%). Co-occurrence of intraoperative hypotension, hypoxaemia, and anaemia was associated with increased risk of morbidity (RR=3.56; 95% CI, 1.64-7.71) and mortality (RR=19.80; 95% CI, 5.87-66.7). Conclusions: Variability in physiological thresholds that triggered an intervention, and the impact of poor tissue oxygenation on patient's outcome, highlight the need for more standardised perioperative management guidelines for neonates and infants