ABSTRACT BACKGROUND: The authors of randomized controlled trials will usually claim that they have met the randomization process criterion. However, sequence generation schemes differ and some schemes that are claimed to be randomized are not genuinely randomized. Even less well understood, and often more difficult to ascertain, is whether the allocation was really concealed. OBJECTIVE: To detect the extent of control over selection bias, in a comparison between two Cochrane groups: oral health and otorhinolaryngology; and to describe the methods used to control for this bias. DESIGN AND SETTING: Cross-sectional study conducted in a public university in São Paulo, Brazil. METHODS: The risk of selection bias in 1,714 records indexed in Medline database up to 2018 was assessed, independent of language and access. Two dimensions implicated in the allocation were considered: generation of the allocation sequence; and allocation concealment. RESULTS: We included 420 randomized controlled trials and all of them were evaluated to detect selection bias. In the sample studied, only 28 properly controlled the selection bias. Lack of control over selection bias was present in 80% of the studies evaluated in both groups. CONCLUSION: The two groups were similar regarding control over selection bias. They are also similar to the methods used. The dimension of allocation concealment appears to be a limiting factor with regard to production of randomized controlled trials with low risk of selection bias. The quality of reporting in studies on oral health and otorhinolaryngology is suboptimal and needs to be improved, in line with other fields of healthcare.

OBJECTIVE: To evaluate the validity of the Qualis database in identifying the levels of scientific evidence and the quality of randomized controlled trials indexed in the Lilacs database. METHODS: We selected 40 open-access journals and performed a page-by-page hand search, to identify published articles according to the type of study during a period of six years. Classification of studies was performed by independent reviewers assessed for their reliability. Randomized controlled trials were identified for separate evaluation of risk of bias using four dimensions: generation of allocation sequence, allocation concealment, blinding, and incomplete outcome data. The Qualis classification was considered to be the outcome variable. The statistical tests used included Kappa, Spearman's correlation, Kendall-tau and ordinal regressions. RESULTS: Studies with low levels of scientific evidence received similar Qualis classifications when compared to studies with high levels of evidence. In addition, randomized controlled trials with a high risk of bias for the generation of allocation sequences and allocation concealment were more likely to be published in journals with higher Qualis levels. DISCUSSION: The hierarchy level of the scientific evidence as classified by type of research design, as well as by the validity of studies according to the bias control level, was not correlated or associated with Qualis stratification. CONCLUSION: Qualis classifications for journals are not an approximate or indirect predictor of the validity of randomized controlled trials published in these journals and are therefore not a legitimate or appropriate indicator of the validity of randomized controlled trials.

O objetivo deste estudo foi avaliar custos de implantação e manutenção da assistência odontológica no setor público. Os custos foram atualizados/depreciados de acordo com a vida útil e considerados na perspectiva do serviço e da sociedade. Os resultados mostraram que, para o serviço, o custo total de implantação de uma unidade odontológica com sete consultórios foi de R$ 860.643,67 no primeiro ano e R$ 545.419,23 para manutenção, sendo clínica geral a especialidade mais cara. Para a sociedade, o custo total foi de R$ 990.065,06 (implantação) e R$ 668.369,55 (manutenção) e a especialidade mais cara foi prevenção. Custos de capital representaram um pequeno percentual dos custos de uma unidade odontológica, entretanto, deveriam ser considerados, pois podem modificar os resultados. Devido ao alto custo, intervenções preventivo-promocionais realizadas no ambiente clínico não deveriam ser recomendadas, devendo ser substituídas por ações populacionais amplas e de menor custo, uma vez que valores consideráveis necessitam ser desembolsados pela população de baixa renda para participar de programas públicos gratuitos.

The aim of this study was to assess the costs of setting up and maintaining dental care in the public sector. Costs were updated or depreciated according to the service's lifespan and were analyzed from the perspective of the service itself and society. According to the findings, for the service the total cost of setting up a dental care unit with seven rooms was BRL$860.643.67 in the first year, plus BRL$545,419.23 for maintenance, and clinical dental care was the most expensive specialty. For society, the total cost was BRL$990,065.06 (implementation) and BRL$668,369.55 (maintenance), and the most expensive specialty was prevention (US$1.00 = BRL$1.62). Capital costs represented a small percentage of total costs for a dental care unit, but they need to be considered, since they can modify the results. Due to the high costs, preventive and promotional interventions should not be performed in the clinical setting, but should be replaced by broader and less expansive population-based interventions, since considerable sums need to be spent by the low-income population to participate in free public programs.

O objetivo deste estudo foi avaliar custos de implantação e manutenção da assistência odontológica no setor público. Os custos foram atualizados/depreciados de acordo com a vida útil e considerados na perspectiva do serviço e da sociedade. Os resultados mostraram que, para o serviço, o custo total de implantação de uma unidade odontológica com sete consultórios foi de R$ 860.643,67 no primeiro ano e R$ 545.419,23 para manutenção, sendo clínica geral a especialidade mais cara. Para a sociedade, o custo total foi de R$ 990.065,06 (implantação) e R$ 668.369,55 (manutenção) e a especialidade mais cara foi prevenção. Custos de capital representaram um pequeno percentual dos custos de uma unidade odontológica, entretanto, deveriam ser considerados, pois podem modificar os resultados. Devido ao alto custo, intervenções preventivo-promocionais realizadas no ambiente clínico não deveriam ser recomendadas, devendo ser substituídas por ações populacionais amplas e de menor custo, uma vez que valores consideráveis necessitam ser desembolsados pela população de baixa renda para participar de programas públicos gratuitos.

The aim of this study was to assess the costs of setting up and maintaining dental care in the public sector. Costs were updated or depreciated according to the service's lifespan and were analyzed from the perspective of the service itself and society. According to the findings, for the service the total cost of setting up a dental care unit with seven rooms was BRL$860.643.67 in the first year, plus BRL$545,419.23 for maintenance, and clinical dental care was the most expensive specialty. For society, the total cost was BRL$990,065.06 (implementation) and BRL$668,369.55 (maintenance), and the most expensive specialty was prevention (US$1.00 = BRL$1.62). Capital costs represented a small percentage of total costs for a dental care unit, but they need to be considered, since they can modify the results. Due to the high costs, preventive and promotional interventions should not be performed in the clinical setting, but should be replaced by broader and less expansive population-based interventions, since considerable sums need to be spent by the low-income population to participate in free public programs.

OBJETIVO: Avaliar as propriedades psicométricas do Oral Heath Impact Profile (OHIP-14) para mensurar a condição de saúde bucal. MÉTODOS: Foram utilizados dados secundários de um inquérito epidemiológico realizado em 2001 pela Secretaria da Saúde do município de Sabará, MG, que consistiram de 312 formulários de exames da cárie dentária e de questionários de necessidade percebida (OHIP), referentes escolares de 12 anos, da rede pública. A confiabilidade do OHIP-14 foi avaliada utilizando os coeficientes alfa de Cronbach e correlação intraclasse. Para avaliação da validade de conteúdo foram realizadas a correlação de Pearson e regressão logística e para avaliar a validade de constructo foram realizados o teste "t" de Student e o de Tukey Kramer. RESULTADOS: A perda dos participantes foi baixa (entre 85 e 100%). A prevalência de cárie foi muito baixa sendo que 59,0% da amostra não apresentou cárie detectável. O modelo de regressão logística indicou valores de predição altos para declaração de necessidade de tratamento e médios para percepção de cárie dentária. A comparação entre diferentes escores médios do OHIP, de acordo com três categorias do índice de superfícies cariadas perdidas e obturadas (CPO-S), indicou diferença significante apenas para as categorias incapacidade social e deficiência. CONCLUSÕES: Os resultados indicam que o adolescente não relatou alta prevalência de doença bucal percebida. O OHIP está associado à necessidade percebida de tratamento, à declaração da presença de cárie dentária e ao aumento do índice CPO-S. Os resultados sugerem que o OHIP apresenta boas propriedades psicométricas quando aplicado em crianças, indicando ser um instrumento promissor para rastreamento de grupos prioritários para acesso ao serviço.

OBJECTIVE: To evaluate the psychometric properties of the Oral Heath Impact Profile (OHIP-14) to measure oral health in children. METHODS: The OHIP-14 questionnaire was applied to 312 schoolchildren aged 12 years residing in Sabará, Brazil, in 2001. OHIP-14's reliability was evaluated using Cronbach's alpha and correlation intraclass coefficient. For examining content validity, Pearson's correlation and logistic regression analysis were applied. For construct validity, Student's t-test and Tukey-Kramer test were used. RESULTS: Tooth loss among the subjects was low in this study (between 85% and 100%). Caries prevalence was very low and not detectable in 59.0% of the sample. The logistic regression model showed high predictive values for reporting treatment need and intermediate values for dental caries perception. The comparison between different OHIP average scores, according to the DMF-S index's three categories of decayed, missing, filled surfaces, indicated significant difference only for the categories social disability and deficit. CONCLUSIONS: The study results indicated that the adolescents did not report high prevalence of oral conditions. The OHIP was associated with perceived treatment need, reporting of dental caries and increased DMF-S index. These results suggest that the OHIP has good psychometric properties when applied to children and could be a promising instrument for screening priority care groups.

OBJETIVO: Avaliar as propriedades psicométricas do Oral Heath Impact Profile (OHIP-14) para mensurar a condição de saúde bucal. MÉTODOS: Foram utilizados dados secundários de um inquérito epidemiológico realizado em 2001 pela Secretaria da Saúde do município de Sabará, MG, que consistiram de 312 formulários de exames da cárie dentária e de questionários de necessidade percebida (OHIP), referentes escolares de 12 anos, da rede pública. A confiabilidade do OHIP-14 foi avaliada utilizando os coeficientes alfa de Cronbach e correlação intraclasse. Para avaliação da validade de conteúdo foram realizadas a correlação de Pearson e regressão logística e para avaliar a validade de constructo foram realizados o teste "t" de Student e o de Tukey Kramer. RESULTADOS: A perda dos participantes foi baixa (entre 85 e 100%). A prevalência de cárie foi muito baixa sendo que 59,0% da amostra não apresentou cárie detectável. O modelo de regressão logística indicou valores de predição altos para declaração de necessidade de tratamento e médios para percepção de cárie dentária. A comparação entre diferentes escores médios do OHIP, de acordo com três categorias do índice de superfícies cariadas perdidas e obturadas (CPO-S), indicou diferença significante apenas para as categorias incapacidade social e deficiência. CONCLUSÕES: Os resultados indicam que o adolescente não relatou alta prevalência de doença bucal percebida. O OHIP está associado à necessidade percebida de tratamento, à declaração da presença de cárie dentária e ao aumento do índice CPO-S. Os resultados sugerem que o OHIP apresenta boas propriedades psicométricas quando aplicado em crianças, indicando ser um instrumento promissor para rastreamento de grupos prioritários para acesso ao serviço.

OBJECTIVE: To evaluate the psychometric properties of the Oral Heath Impact Profile (OHIP-14) to measure oral health in children. METHODS: The OHIP-14 questionnaire was applied to 312 schoolchildren aged 12 years residing in Sabará, Brazil, in 2001. OHIP-14's reliability was evaluated using Cronbach's alpha and correlation intraclass coefficient. For examining content validity, Pearson's correlation and logistic regression analysis were applied. For construct validity, Student's t-test and Tukey-Kramer test were used. RESULTS: Tooth loss among the subjects was low in this study (between 85% and 100%). Caries prevalence was very low and not detectable in 59.0% of the sample. The logistic regression model showed high predictive values for reporting treatment need and intermediate values for dental caries perception. The comparison between different OHIP average scores, according to the DMF-S index's three categories of decayed, missing, filled surfaces, indicated significant difference only for the categories social disability and deficit. CONCLUSIONS: The study results indicated that the adolescents did not report high prevalence of oral conditions. The OHIP was associated with perceived treatment need, reporting of dental caries and increased DMF-S index. These results suggest that the OHIP has good psychometric properties when applied to children and could be a promising instrument for screening priority care groups.