Validation of a hepatitis C screening tool in primary care
ABSTRACT Although hepatitis C virus (HCV) has an estimated national prevalence of 1.8%, testing rates are lower than those recommended by guidelines, particularly in primary care. A critical step is the ability to identify patients at increased risk who should be screened. We sought to prospectively derive and validate a clinical predication tool to assist primary care providers in identifying patients who should be tested for HCV antibodies.
A total of 1000 randomly selected patients attending an inner-city primary care clinic filled out a 27-item questionnaire assessing 5 HCV risk factor domains: work, medical, exposure, personal care, and social history. Afterward, the patients underwent HCV antibody testing. Multivariable logistic regression analysis was performed to identify risk factors associated with HCV antibodies.
There was an 8.3% (95% confidence interval, 6.7%-10.2%) prevalence of HCV antibodies. The patients who were HCV antibody positive were more likely to be male, older, and insured by Medicaid (P < or = .02). Those who had risk factors within the medical, exposure, and social history domains were more likely to be HCV antibody positive. The area under the receiver operating characteristic curve for the screening tool based on these 3 domains was 0.77. With an increasing number of positive domains, there was a higher likelihood of HCV antibody positivity. Only 2% of patients with 0 risk factors had HCV antibodies.
A prediction tool can be used to accurately identify patients at high risk of HCV who may benefit from serologic screening. Future studies should assess whether wider use of this tool may lead to improved outcomes.
- SourceAvailable from: hep.org.au
Conference Paper: Adaptation of Spread Spectrum Digital Voice Radios[Show abstract] [Hide abstract]
ABSTRACT: Integrated spread spectrum modem and digital voice processor designs can achieve processing gain adaptation without communication interruption. Only those adaptations that hold constant PN chip and/or FH hop rate to avoid modem resynchronization, are considered useful. Sync outages can render modem processing gain advantages ineffective. Variable chip embedding, data redundancy, and header insertion signaling techniques can modify modem processing gain without disturbing operation of the interfacing digital voice processor.Military Communications Conference, 1985. MILCOM 1985. IEEE; 11/1985
- [Show abstract] [Hide abstract]
ABSTRACT: A passive dendritic cable model, derived from the detailed structure of CA1 pyramidal neurons, has been used to compare predictions of electrotonic length, synaptic potential generation and dendritic conduction with physiologic measurements. Comparison of fast excitatory synaptic potentials from experimental and modeling approaches has indicated probable passive conduction of these signals in pyramidal neuron dendrites. This modeling approach has been extended to simulation of inhibitory and slow excitatory synaptic signals, in terms of location, magnitude and waveform of the conductance change input. The inclusion of specific dendritic structure allows the analysis of electrotonic length and synaptic potentials in normal and pathological dendrites, as in the evaluation of dendritic properties in animal models of senescence and epilepsy