[Relationship between socio-economic factors and tuberculosis using negative binomial and Poisson regression models]

Tuberculosis [TB] is the most important cause of death worldwide. The main reason for the increasing global burden of TB are severe poverty and class distinctions between rich and poor population groups in various communities. This study was performed to determine the relationship between socio-economic factors and TB using negative binomial and Poisson regression models. This descriptive - analytic study was conducted on 11320 TB affected patients in Iran during 2010. Data was gathered from the Iranian Ministry of Health and Medical Education. The relationship between the numbers of cases with socio-economic indicators was determined using negative binomial and Poisson models. Fitting models were compared using AIC [Akaike Information Criterion] and BIC [Bayesian Information Criterion]. The Poisson regression model showed a significant relationship between the TB mortality rate and socio-economic factors [P<0.05]. Negative binomial regression model showed a significant relationship between TB and unemployment, illiterate, immigration and urban residency [P<0.05]. Negative binomial regression model showed no relationship between TB and family size, physicians' ratio to the number of population centers and annual average income. There is a significant impact of socio-economic factors with the number of TB cases. Negative binomial regression model is suitable for accountable data in comparision with Poisson regression model

[Evaluation of pattern reversal visual evoked potential components in albinism]

Albinism is a genetic disorder that affects melanin synthesis of the human being. Although not very common, it has serious effects on the visual system, particularly reduced visual acuity. The pattern visual evoked potential is a reliable objective technique for diagnosing the latent and misrouting of this condition. The aim of this study was to use and evaluate the importance and accuracy of a single channel PVEP instead of common multichannel PVEP for detecting asymmetric responses between the latent and misrouting albinism and control group. In this cross sectional study, the pattern visual evoked potentials were measured using 60 min/arc check sizes with temporal frequency of 3 Hz in twenty four suspected albino people ages of 5 to 43 years [mean age of 19 years]. Amplitude and latencies time were measured for both the right and left, and then the results were compared with an age- and gender matched, normal group. The latency waves of N75, P100, N135 and P1N1 [N75-P100] amplitude between two eyes of the albino people showed a statistically significant difference. The asymmetric responses of PVEP between two of the albino people were significantly larger than than control group. There is a strong relation between asymmetric responses of single channel PVEP and other clinical signs of albinism, which make this method as a useful objective technique for diagnosing the latent albinism