Sample size requirement in trials that use the composite endpoint major adverse cardiovascular events (MACE): new insights

Composite endpoints; Correlation; Sample sizePuntos finales compuestos; Correlación; Tamaño de la muestraPunts finals compostos; Correlació, Grandària de la mostraBackground The real impact of the degree of association (DoA) between endpoint components of a composite endpoint (CE) on sample size requirement (SSR) has not been explored. We estimate the impact of the DoA between death and acute myocardial infarction (AMI) on SSR of trials using use the CE of major adverse cardiac events (MACE). Methods A systematic review and quantitative synthesis of trials that include MACE as the primary outcome through search strategies in MEDLINE and EMBASE electronic databases. We limited to articles published in journals indexed in the first quartile of the Cardiac & Cardiovascular Systems category (Journal Citation Reports, 2015–2020). The authors were contacted to estimate the DoA between death and AMI using joint probability and correlation. We analyzed the SSR variation using the DoA estimated from RCTs. Results Sixty-three of 134 publications that reported event rates and the therapy effect in all component endpoints were included in the quantitative synthesis. The most frequent combination was death, AMI, and revascularization (n = 20; 31.8%). The correlation between death and AMI, estimated from 5 trials¸ oscillated between − 0.02 and 0.31. SSR varied from 14,602 in the scenario with the strongest correlation to 12,259 in the scenario with the weakest correlation; the relative impact was 16%. Conclusions The DoA between death and AMI is highly variable and may lead to a considerable SSR variation in a trial including MACE.Intramural CIBER-ESP PR22 from the Center for Biomedical Research in Epidemiology and Public Health Network (CIBERESP)

Breast Cancer Screening Coverage with clinical examination and Mammography Among insured women in Bogota

Objetivo: Determinar la cobertura de examen clínico y mamografía de tamización para cáncer de mama en un grupo de mujeres bogotanas afiliadas a seguros de salud. Métodos: Se realizó una encuesta telefónica a 4.526 mujeres entre 50 y 69 años, residentes en Bogotá y en municipios vecinos, afiliadas a tres compañías de seguros de salud. Se excluyeron las mujeres con antecedente personal de cáncer de mama. La cobertura de tamización se valoró como la proporción de mujeres con antecedente de mamografía y examen clínico de la mama. Se estimó la frecuencia en la vida, en los últimos dos años y en el último año. Se analizaron factores asociados a la práctica de tamización, mediante el cálculo de OR ajustados. Resultados: La frecuencia de vida de uso del examen clínico y mamografía fue de 59,3% y 79,8% respectivamente; el 49,7% y el 65,6% de las mujeres se realizó los exámenes con fines de tamización; el resto, con fines diagnósticos (sintomáticas). El 34,2% tenía examen clínico en el último año, y el 54%, mamografía en los últimos dos años. La educación y el antecedente familiar de cáncer de mama estuvieron asociados a la práctica de tamización. Conclusiones: La cobertura de examen clínico de la mama como método de tamización es baja. Las coberturas de mamografía son superiores a lo exigido por el sistema colombiano, pero inferiores a las coberturas útiles reportadas en países desarrollados.Objectives: To determine the coverage of clinical breast examination (CBE) and mammography for screening of breast cancer among a group of insured women in Bogotá. Methods: A telephone survey was carried out with 4,526 women between the ages of 50 and 69, residing in Bogotá or its suburbs, who were insured by one of three commercial health plans. Women with a history of breast cancer were excluded. Screening coverage was estimated as the proportion of women who had had a mammography or CBE. Estimates were established for lifetime frequency, two years prior the survey, and one year prior the survey. Factors associated with screening procedures were analyzed with calculations based on adjusted OR. Results: Lifetime frequency of CBE was 59.3% and 79.8% for mammography; and 49.7% and 65.6% of women respectively underwent the tests for screening purposes; the remainder, for diagnostic purposes (breast symptoms). CBE reported a 34.2% one year coverage and mammography reported a 54% two years coverage. Screening was associated to cancer education and family history of breast cancer. Conclusion: Coverage of CBE for screening purposes is low. Mammography coverage is above that required by the Colombian Health Ministry, but below that reported by developed countrie

Bladder cancer index: cross-cultural adaptation into Spanish and psychometric evaluation

BACKGROUND: The Bladder Cancer Index (BCI) is so far the only instrument applicable across all bladder cancer patients, independent of tumor infiltration or treatment applied. We developed a Spanish version of the BCI, and assessed its acceptability and metric properties. METHODS: For the adaptation into Spanish we used the forward and back-translation method, expert panels, and cognitive debriefing patient interviews. For the assessment of metric properties we used data from 197 bladder cancer patients from a multi-center prospective study. The Spanish BCI and the SF-36 Health Survey were self-administered before and 12 months after treatment. Reliability was estimated by Cronbach's alpha. Construct validity was assessed through the multi-trait multi-method matrix. The magnitude of change was quantified by effect sizes to assess responsiveness. RESULTS: Reliability coefficients ranged 0.75-0.97. The validity analysis confirmed moderate associations between the BCI function and bother subscales for urinary (r = 0.61) and bowel (r = 0.53) domains; conceptual independence among all BCI domains (r ≤ 0.3); and low correlation coefficients with the SF-36 scores, ranging 0.14-0.48. Among patients reporting global improvement at follow-up, pre-post treatment changes were statistically significant for the urinary domain and urinary bother subscale, with effect sizes of 0.38 and 0.53. CONCLUSIONS: The Spanish BCI is well accepted, reliable, valid, responsive, and similar in performance compared to the original instrument. These findings support its use, both in Spanish and international studies, as a valuable and comprehensive tool for assessing quality of life across a wide range of bladder cancer patients