RESUMO
OBJECTIVE: This study was carried out to evaluate whether patients with cystic fibrosis (CF) who are socioeconomically disadvantaged, have a different outcome than higher-income patients. Medicaid insurance coverage was used as a proxy of low family income. STUDY DESIGN: A cross-sectional analysis was performed on a group of patients younger than 21 years of age seen at the University of North Carolina CF Center in 1994. RESULTS: The difference in median age at diagnosis for Medicaid (132 days) and non-Medicaid (177 days) patients was not statistically significant (p = 0.17). Medicaid patients' mean maximum percent predicted forced expiratory volume in 1 second for the year was 11.6% less than that of the non-Medicaid group (p = 0.01); this difference was constant across age. Medicaid patients averaged 0.8 more admissions for the year (p < 0.01) and 8.8 more days (p < 0.01) in the hospital but received the same amount of outpatient intravenous therapy. They also had 1.20 more outpatient visits to the center during the year (p = 0.02). CONCLUSIONS: Medicaid patients with CF have worse lung function and require more treatment for pulmonary exacerbations than their more advantaged counter-parts. This difference appears to begin early in life, does not increase with age, and is not explained by inadequate access to outpatient specialty care or delayed diagnosis. Other explanations such as inadequate access to primary care, poor adherence to prescribed regimens, or greater exposure to pollutants (e.g., environmental tobacco smoke) are speculative.
Assuntos
Fibrose Cística/fisiopatologia , Classe Social , Adolescente , Criança , Estudos Transversais , Fibrose Cística/epidemiologia , Fibrose Cística/genética , Feminino , Volume Expiratório Forçado , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
OBJECTIVES: To evaluate the diagnostic accuracy of the clinical examination in detecting hypoxemia in infants with lower respiratory tract illness. DESIGN: Cross-sectional study. SETTING: Three university pediatric outpatient departments and one private pediatric practice. PATIENTS: Healthy infants less than 1 year of age seen between December and March 1989 and 1990, with symptoms suggesting acute lower respiratory tract illness. MAIN OUTCOME MEASURES: The test characteristics of 27 elements of the clinical examination, as well as the accuracy of the overall examination and the components of the examination in detecting oxygen saturation < 95% measured by pulse oximetry. Reliability of clinical examination findings. RESULTS: None of the 27 clinical findings had sensitivities that would make them useful diagnostic tests for hypoxemia. By combining all the clinical findings, however, we found good diagnostic accuracy (area under the receiver operator characteristic curve 0.90). Three groups of clinical findings--social interactiveness, respiratory effort, and physical appearance--accounted for much of the diagnostic accuracy of the examination. Auscultatory findings contributed little. In these three groups, five clinical findings accounted for almost all the accuracy: attentiveness, consolability, respiratory effort, color, and movement. Together, these findings also had good accuracy (area under the receiver operator characteristic curve 0.95). CONCLUSIONS: A small number of clinical observations may be mostly responsible for the diagnostic value of the clinical examination of infants with symptoms of LRI. Concentrating on a limited group of findings appears to enhance the accuracy of the examination in detecting hypoxemia.
Assuntos
Hipóxia/diagnóstico , Infecções Respiratórias/complicações , Estudos Transversais , Feminino , Humanos , Hipóxia/etiologia , Lactente , Masculino , Variações Dependentes do Observador , Oxigênio/sangue , Exame Físico , Reprodutibilidade dos Testes , Infecções Respiratórias/sangue , Sensibilidade e EspecificidadeRESUMO
Improperly designed evaluations of diagnostic tests may lead to inaccurate conclusions about a test's accuracy. One problem, verification bias, occurs if subjects are not equally likely to have the diagnosis verified by a gold-standard evaluation and if selection for further evaluation is dependent on the diagnostic test result. To determine whether verification bias is a problem in pediatric studies of diagnostic tests, we conducted a critical appraisal of all studies evaluating diagnostic tests published in three pediatric journals during a 3-year period. Thirty-six percent were subject to verification bias. The most prevalent cause was restriction of the patient sample to those whose diagnosis had been verified by a gold standard evaluation, when the decision to obtain the gold standard was influenced by the diagnostic test result. Verification bias may have serious effects on the estimated sensitivity and specificity of a test. Improved awareness of the potential for verification bias may help physicians improve their selection and interpretation of diagnostic tests and thereby improve the quality and efficiency of patient care.
Assuntos
Viés , Testes Diagnósticos de Rotina/estatística & dados numéricos , Pediatria , Criança , Estudos de Avaliação como Assunto , Humanos , Valor Preditivo dos Testes , Sensibilidade e EspecificidadeRESUMO
Because febrile infants with no obvious source of bacterial infection may have bacteremia, and because bacteremia is difficult to diagnose on clinical grounds, we used decision analysis to evaluate whether such infants should be treated with antibiotics, tested further, or sent home. Using a simple decision tree, we found that the decision to give empiric antibiotic treatment is the decision of choice. The difference in quality-adjusted life expectancy between the "best" and "worst" decisions was only 11 days. However, this difference translated to prevention of death or permanent disability in 60 cases per 100,000 febrile children. Further, empiric treatment remained the best management alternative unless the probability of bacteremia was less than 1.4% (less than any published prevalence), or the efficacy of treatment was less than 21%. Our analysis demonstrated that a test with far greater sensitivity than leukocyte count or other tests currently in use is needed to justify testing rather than treating empirically. Further, an enormous patient population would be needed to find a difference of both clinical and statistical significance between treated and untreated patients in a controlled trial. In the absence of such trials, we recommend blood culture and empiric antibiotic treatment of all infants at risk for occult bacteremia.