Introduction. Parental hypercholesterolemia would be a better predictor of hypercholesterolemia than family medical history in children. Objectives. To compare the strength of association and predictive values of parental hypercholesterolemia versus a positive family history in pediatric hypercholesterolemia. Material and methods. Cross-sectional, analytical study. Cholesterol levels were measured in children aged ≥ 6 and < 12 years and in their biological parents. A survey was administered to parents. The association was estimated using the odds ratio (OR), and its predictive value was determined. The relationship between hypercholesterolemia in parents and their children was studied with multilevel regression. Results. A total of 332 children, 304 mothers, and 206 fathers were assessed. A cholesterol level ≥ 240 mg/dL in one or both parents and ≥ 200 mg/dL in children showed: OR= 6.40; 95 % confidence interval (CI)= 2.85-14.48; p < 0.0001; sensitivity= 69 %; specihcity= 74 %; positive predictive value (PPV)= 34 %; negative predictive value (NPV)= 93 %; positive likelihood ratio (LR+)= 2.69; negative likelihood ratio (LR-)= 0.42. Family medical history versus children with cholesterol level ≥ 200 showed: OR= 1.86; 95 % CI= 0.84-4.11; p= 0.1272; sensitivity= 69 %; specihcity= 46 %; PPV= 19 %; NPV= 89 %; LR+= 1.27; LR-= 0.68. Cholesterol was 2.9 and 2.5 mg/dL higher per every 10 mg/dL of increased cholesterol in mothers and fathers, respectively. Conclusions: Parental hypercholesterolemia was significantly associated with hypercholesterolemia in children and showed a higher predictive power than a positive family medical history.

Introducción.La hipercolesterolemia en los padres sería mejor predictor de hipercolesterolemia en niños que la historia clínica familiar. Objetivos. Comparar las fuerzas de asociación y los valores de predicción de la hipercolesterolemia en padres y la historia clínica familiar positiva con la hipercolesterolemia en hijos. Material y métodos. Estudio analítico, transversal. Se dosó colesterolemia en niños ≥ 6 y < 12 años y sus padres biológicos. Se realizó una encuesta a los padres. Se evaluó la asociación mediante el cálculo de odds ratio. Se determinó su valor de predicción. Se estudió la relación entre la hipercolesterolemia en padres y en hijos usando la regresión multinivel. Resultados. Se evaluaron 332 niños, 304 madres y 206 padres. El análisis entre uno/ambos progenitores con colesterolemia ≥ 240 mg/dl y niños ≥ 200 mg/dl mostró OR= 6,40; IC95 % =2,85-14,48; p <0,0001; sensibilidad= 69 %; espedhcidad= 74 %; valor predictivo positivo (VPP)= 34 %; valor predictivo negativo (VPN)= 93 %; razones de verosimilitud positiva (RVP)= 2,69; negativa (RVN)= 0,42. La historia clínica familiar vs. niños con colesterolemia ≥ 200 arrojó OR= 1,86; IC95 %= 0,84-4,11; p= 0,1272; sensibilidad= 69 %; especificidad= 46 %; VPP= 19 %; VPN= 89 %; RVP= 1,27; RVN= 0,68. Los hijos tuvieron 2,9 y 2,5 más mg/dl de colesterol por cada 10 mg/dl de aumento en colesterol en madres y padres, respectivamente. Conclusiones: La hipercolesterolemia en padres se asoció significativamente con la hipercolesterolemia en hijos y mostró mayor poder de predicción que la historia clínica familiar positiva.

The "Safe Community" is a community-based intervention model by the World Health Organization (WHO) for control and prevention of injuries and violence. The program is directed towards the prevention of all types of injuries and to all age groups, environments and situations. In this model, the community identifies its organizational needs, defines interest areas with participation by everybody, designs and implements interventions by means of inter-sector work using local, low cost solutions, and guarantees the sustainability of the programs by means of governmental commitment and alliances among different organizations. This model has demonstrated its effectiveness in different contexts, including developing countries. In Latin America, a "Safe Community" has been certified in Chile, an example to be followed for facing the problem of injuries and violence in the region.

La comunidad segura es un modelo de intervención de la Organización Mundial de la Salud (OMS) para el control y la prevención de las lesiones y la violencia basada en la comunidad. El programa está dirigido a la prevención de todos los tipos de lesiones y todos los grupos de edad, ambientes y situaciones. En este modelo, la comunidad identifica sus necesidades organizativas, define las áreas de interés con la participación de todos, diseña e instituye las intervenciones por medio de un trabajo intersectorial y ofrece soluciones locales de bajo costo; asimismo, garantiza la sostenibilidad de los programas mediante el compromiso gubernamental y las alianzas entre diferentes organizaciones. Este modelo ha demostrado su efectividad en diferentes contextos, incluidos los países en desarrollo. En Latinoamérica se ha certificado una "comunidad segura" en Chile, un ejemplo a seguir para enfrentar el problema de las lesiones y la violencia en la región.

The "Safe Community" is a community-based intervention model by the World Health Organization (WHO) for control and prevention of injuries and violence. The program is directed towards the prevention of all types of injuries and to all age groups, environments and situations. In this model, the community identifies its organizational needs, defines interest areas with participation by everybody, designs and implements interventions by means of inter-sector work using local, low cost solutions, and guarantees the sustainability of the programs by means of governmental commitment and alliances among different organizations. This model has demonstrated its effectiveness in different contexts, including developing countries. In Latin America, a "Safe Community" has been certified in Chile, an example to be followed for facing the problem of injuries and violence in the region.

La comunidad segura es un modelo de intervención de la Organización Mundial de la Salud (OMS) para el control y la prevención de las lesiones y la violencia basada en la comunidad. El programa está dirigido a la prevención de todos los tipos de lesiones y todos los grupos de edad, ambientes y situaciones. En este modelo, la comunidad identifica sus necesidades organizativas, define las áreas de interés con la participación de todos, diseña e instituye las intervenciones por medio de un trabajo intersectorial y ofrece soluciones locales de bajo costo; asimismo, garantiza la sostenibilidad de los programas mediante el compromiso gubernamental y las alianzas entre diferentes organizaciones. Este modelo ha demostrado su efectividad en diferentes contextos, incluidos los países en desarrollo. En Latinoamérica se ha certificado una "comunidad segura" en Chile, un ejemplo a seguir para enfrentar el problema de las lesiones y la violencia en la región.

Background: Clinical research stresses the need for evidence as a basis for setting research agendas. The extent to which current clinical research involves recent advances in biostatistics is not well known. Aim: This manuscript focuses on the use of interim analyses accumulating data in clinical trials. Material and Methods: A PubMed search was conducted for the period 1990-2000. Keywords used included ‘interim analysis’, ‘alpha-spending function’, and ‘early termination’, after subsetting to ‘randomised controlled trials (RCT)’ that were ‘multicenter’ since these particular studies are more likely to have external monitoring boards conducting interim analyses. Studies were grouped by clinical discipline and also by journals of high or low impact index. Results: Thirteen thousand two hundred eighty two articles with both ‘RCT’ and ‘multicenter’ were found. Of these, the ‘interim analysis’ keyword yielded 879 articles, of which only 163 (19%) studies reported their methodology. The percentages varied by clinical discipline and by journal type. A 25% random sample of the articles were further reviewed to investigate the appropriateness of the interim analysis methods used. Discussion: Recent articles in the medical literature attempt to make the interim analysis methods more accessible to clinicians. However, further training of statisticians involved in clinical trials is needed as well (Rev Méd Chile 2001; 129: 983-8)

Interim analysis of data accumulated in clinical trials is one aspect of the monitoring of the study progress. It is usually done to assess whether there are significant differences in efficacy between the experimental and control treatment groups, in order to decide whether to stop or no the trial prematurely. Among many reasons for early interruption of a trial is the ethical consideration that subjects should not be exposed to an unsafe, inferior or ineffective treatment. Statistical methods suited for doing interim analysis, that allow to control the probability of incorrectly rejecting the null hypothesis of no treatment differences, are often not well understood by researchers. In this article we present an intuitive, non-mathematical explanation and review of the statistical methods for doing interim analysis in clinical trials along with an illustrative example of the application of the methods on a hypothetical dataset (Rev Méd Chile 2000; 128: 935-41).